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KASAN: slab-out-of-bounds Read in fb_pad_unaligned_buffer

Status: moderation: reported on 2024/04/29 15:21
Subsystems: fbdev
[Documentation on labels]
Reported-by: syzbot+454728428735cd282e12@syzkaller.appspotmail.com
First crash: 21d, last: 21d

Sample crash report:
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac28 by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac28 by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac29 by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac29 by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac2a by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac2a by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x43c/0x470 drivers/video/fbdev/core/fbmem.c:116
Read of size 1 at addr ffff88804496ac2b by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x43c/0x470 drivers/video/fbdev/core/fbmem.c:116
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x44b/0x470 drivers/video/fbdev/core/fbmem.c:119
Read of size 1 at addr ffff88804496ac2b by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x44b/0x470 drivers/video/fbdev/core/fbmem.c:119
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac2c by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac2c by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac2d by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac2d by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
Read of size 1 at addr ffff88804496ac2e by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x3ec/0x470 drivers/video/fbdev/core/fbmem.c:108
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
Read of size 1 at addr ffff88804496ac2e by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x406/0x470 drivers/video/fbdev/core/fbmem.c:110
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x317/0x3d0 drivers/video/fbdev/core/fbcon.c:1288
 con_flush drivers/tty/vt/vt.c:2762 [inline]
 do_con_write+0x1009/0x7bb0 drivers/tty/vt/vt.c:3091
 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
 process_output_block drivers/tty/n_tty.c:574 [inline]
 n_tty_write+0x426/0x1150 drivers/tty/n_tty.c:2379
 iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
 file_tty_write.constprop.0+0x51b/0x9b0 drivers/tty/tty_io.c:1096
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6de/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b7047dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b6ffff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b705abf80 RCX: 00007f7b7047dea9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00007f7b704ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b705abf80 R15: 00007ffffeee5738
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x44968
head: order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000040 0000000000000000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
head: 00fff80000000002 ffffea0001125a01 dead000000000122 00000000ffffffff
head: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140cc0(GFP_USER|__GFP_COMP), pid 2421, tgid -442441143 (syz-executor.4), ts 2422, free_ts 1940600786909
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x7f/0x1a0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc.cold+0xc/0x61 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 fbcon_set_font+0x434/0xb60 drivers/video/fbdev/core/fbcon.c:2496
 con_font_set drivers/tty/vt/vt.c:4794 [inline]
 con_font_op+0x800/0xf50 drivers/tty/vt/vt.c:4841
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x4ca/0x2f80 drivers/tty/vt/vt_ioctl.c:751
 tty_ioctl+0x660/0x1590 drivers/tty/tty_io.c:2803
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl fs/ioctl.c:890 [inline]
 __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2401 tgid 2398 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3852
 audit_buffer_alloc kernel/audit.c:1790 [inline]
 audit_log_start+0x2bc/0x7d0 kernel/audit.c:1912
 audit_seccomp+0x61/0x280 kernel/auditsc.c:3007
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0x813/0xf30 kernel/seccomp.c:1292
 __secure_computing+0x26c/0x3f0 kernel/seccomp.c:1354
 syscall_trace_enter+0x8b/0x240 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0x1f0/0x260 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804496ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804496ab80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804496ac00: 00 00 fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                  ^
 ffff88804496ac80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff88804496ad00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in fb_pad_unaligned_buffer+0x43c/0x470 drivers/video/fbdev/core/fbmem.c:116
Read of size 1 at addr ffff88804496ac2f by task syz-executor.5/7114

CPU: 1 PID: 7114 Comm: syz-executor.5 Tainted: G    B              6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 fb_pad_unaligned_buffer+0x43c/0x470 drivers/video/fbdev/core/fbmem.c:116
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:130 [inline]
 bit_putcs+0x86a/0xdf0 drivers/video/fbdev/core/bitblit.c:188

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/25 15:18 upstream e88c4cfcb7b8 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root KASAN: slab-out-of-bounds Read in fb_pad_unaligned_buffer
* Struck through repros no longer work on HEAD.