================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:674 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: slab-out-of-bounds in bit_putcs+0xbaa/0xd10 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff888051dc1380 by task syz-executor.2/16524 CPU: 1 PID: 16524 Comm: syz-executor.2 Not tainted 4.19.128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x222 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x88/0x2b9 mm/kasan/report.c:396 __fb_pad_aligned_buffer include/linux/fb.h:674 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xbaa/0xd10 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x424/0x4e0 drivers/video/fbdev/core/fbcon.c:1323 do_update_region+0x398/0x630 drivers/tty/vt/vt.c:683 redraw_screen+0x5e1/0x870 drivers/tty/vt/vt.c:1031 vc_do_resize+0x108e/0x1380 drivers/tty/vt/vt.c:1317 vt_ioctl+0x1fa2/0x2500 drivers/tty/vt/vt_ioctl.c:901 tty_ioctl+0x7a5/0x1420 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ca69 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3bda77ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004f3080 RCX: 000000000045ca69 RDX: 0000000020000000 RSI: 000000000000560a RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000067a R14: 00000000004c975b R15: 00007f3bda77f6d4 Allocated by task 14554: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] fbcon_set_font+0x331/0x870 drivers/video/fbdev/core/fbcon.c:2644 con_font_set drivers/tty/vt/vt.c:4529 [inline] con_font_op+0xd3e/0x1130 drivers/tty/vt/vt.c:4594 vt_ioctl+0xcd0/0x2500 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x7a5/0x1420 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 13361: __cache_free mm/slab.c:3503 [inline] kfree+0xce/0x220 mm/slab.c:3822 sk_prot_free net/core/sock.c:1503 [inline] __sk_destruct+0x57a/0x780 net/core/sock.c:1583 sk_destruct+0xb9/0xf0 net/core/sock.c:1598 __sk_free+0xc2/0x2e0 net/core/sock.c:1609 sk_free+0x3b/0x50 net/core/sock.c:1620 deferred_put_nlk_sk+0x10d/0x280 net/netlink/af_netlink.c:743 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2584 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0x8eb/0x17e0 kernel/rcu/tree.c:2881 __do_softirq+0x26c/0x93d kernel/softirq.c:292 The buggy address belongs to the object at ffff888051dc0b80 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 0 bytes to the right of 2048-byte region [ffff888051dc0b80, ffff888051dc1380) The buggy address belongs to the page: page:ffffea0001477000 count:1 mapcount:0 mapping:ffff88812c3dcc40 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea00014e9f08 ffffea0001481988 ffff88812c3dcc40 raw: 0000000000000000 ffff888051dc0300 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888051dc1280: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888051dc1300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888051dc1380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888051dc1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051dc1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================