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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+0xbaf/0xd10 drivers/video/fbdev/core/bitblit.c:185
Read of size 1 at addr ffff8880b420bdff by task syz-executor.0/11878

CPU: 1 PID: 11878 Comm: syz-executor.0 Not tainted 4.19.172-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/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430
 __fb_pad_aligned_buffer include/linux/fb.h:674 [inline]
 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline]
 bit_putcs+0xbaf/0xd10 drivers/video/fbdev/core/bitblit.c:185
 fbcon_putcs+0x336/0x4f0 drivers/video/fbdev/core/fbcon.c:1269
 do_update_region+0x399/0x630 drivers/tty/vt/vt.c:683
 redraw_screen+0x5e1/0x870 drivers/tty/vt/vt.c:1031
 fbcon_modechanged+0x6df/0x930 drivers/video/fbdev/core/fbcon.c:2685
 fbcon_event_notify+0x197/0x1d80 drivers/video/fbdev/core/fbcon.c:3058
 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93
 __blocking_notifier_call_chain kernel/notifier.c:317 [inline]
 __blocking_notifier_call_chain kernel/notifier.c:304 [inline]
 blocking_notifier_call_chain kernel/notifier.c:328 [inline]
 blocking_notifier_call_chain+0x85/0xa0 kernel/notifier.c:325
 fb_set_var+0xc51/0xe20 drivers/video/fbdev/core/fbmem.c:1042
 do_fb_ioctl+0x3cf/0xb50 drivers/video/fbdev/core/fbmem.c:1115
 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/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: 0033:0x465b09
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3ca2aac188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09
RDX: 0000000020000040 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffc04b9a29f R14: 00007f3ca2aac300 R15: 0000000000022000

Allocated by task 11853:
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15a/0x3c0 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 fbcon_set_font+0x34f/0x8a0 drivers/video/fbdev/core/fbcon.c:2479
 con_font_set drivers/tty/vt/vt.c:4537 [inline]
 con_font_op+0x94b/0xf20 drivers/tty/vt/vt.c:4581
 vt_ioctl+0x116b/0x2380 drivers/tty/vt/vt_ioctl.c:938
 tty_ioctl+0x5b0/0x15c0 drivers/tty/tty_io.c:2669
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/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 10923:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 skb_free_head net/core/skbuff.c:563 [inline]
 skb_release_data+0x6de/0x920 net/core/skbuff.c:583
 skb_release_all net/core/skbuff.c:640 [inline]
 __kfree_skb net/core/skbuff.c:654 [inline]
 consume_skb+0x113/0x3d0 net/core/skbuff.c:714
 mac80211_hwsim_tx_frame+0x133/0x210 drivers/net/wireless/mac80211_hwsim.c:1557
 mac80211_hwsim_beacon_tx+0x3f8/0x680 drivers/net/wireless/mac80211_hwsim.c:1595
 __iterate_interfaces+0x2e1/0x4a0 net/mac80211/util.c:614
 ieee80211_iterate_active_interfaces_atomic+0x8d/0x170 net/mac80211/util.c:650
 mac80211_hwsim_beacon+0xc9/0x190 drivers/net/wireless/mac80211_hwsim.c:1615
 __tasklet_hrtimer_trampoline+0x29/0xa0 kernel/softirq.c:601
 tasklet_action_common.constprop.0+0x265/0x360 kernel/softirq.c:522
 __do_softirq+0x265/0x980 kernel/softirq.c:292

The buggy address belongs to the object at ffff8880b420bcc0
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 319 bytes inside of
 512-byte region [ffff8880b420bcc0, ffff8880b420bec0)
The buggy address belongs to the page:
page:ffffea0002d082c0 count:1 mapcount:0 mapping:ffff88813bff0940 index:0xffff8880b420b7c0
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea0002748648 ffffea0002757048 ffff88813bff0940
raw: ffff8880b420b7c0 ffff8880b420b040 0000000100000005 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880b420bc80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff8880b420bd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880b420bd80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
                                                                ^
 ffff8880b420be00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880b420be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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