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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 ffff88809efbb00a by task syz-executor.2/20357

CPU: 1 PID: 20357 Comm: syz-executor.2 Not tainted 4.19.133-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+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1c7 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:1323
 con_flush drivers/tty/vt/vt.c:2552 [inline]
 do_con_write+0x1269/0x1d90 drivers/tty/vt/vt.c:2757
 con_write+0x22/0xb0 drivers/tty/vt/vt.c:3138
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3c0/0xff0 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x496/0x810 drivers/tty/tty_io.c:1044
 do_loop_readv_writev fs/read_write.c:704 [inline]
 do_loop_readv_writev fs/read_write.c:688 [inline]
 do_iter_write+0x461/0x5d0 fs/read_write.c:962
 vfs_writev+0x153/0x2e0 fs/read_write.c:1005
 do_writev+0x136/0x330 fs/read_write.c:1040
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c1d9
Code: 8d b6 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 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f24348d4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000036e00 RCX: 000000000045c1d9
RDX: 0000000000000001 RSI: 00000000200005c0 RDI: 0000000000000008
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffdd26c925f R14: 00007f24348d59c0 R15: 000000000078bf0c

Allocated by task 15316:
 __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:2644
 con_font_set drivers/tty/vt/vt.c:4529 [inline]
 con_font_op+0xd02/0x10e0 drivers/tty/vt/vt.c:4594
 vt_ioctl+0x116d/0x24d0 drivers/tty/vt/vt_ioctl.c:928
 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 437:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 skb_free_head net/core/skbuff.c:554 [inline]
 skb_release_data+0x6de/0x920 net/core/skbuff.c:574
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb net/core/skbuff.c:645 [inline]
 kfree_skb+0x11a/0x3d0 net/core/skbuff.c:663
 __netif_receive_skb_core+0x535/0x3270 net/core/dev.c:4928
 __netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:4952
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066
 process_backlog+0x239/0x6f0 net/core/dev.c:5848
 napi_poll net/core/dev.c:6271 [inline]
 net_rx_action+0x4ac/0xfb0 net/core/dev.c:6337
 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292

The buggy address belongs to the object at ffff88809efbadc0
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 586 bytes inside of
 1024-byte region [ffff88809efbadc0, ffff88809efbb1c0)
The buggy address belongs to the page:
page:ffffea00027bee80 count:1 mapcount:0 mapping:ffff88812c39cac0 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea0002a47588 ffffea000241df88 ffff88812c39cac0
raw: 0000000000000000 ffff88809efba040 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809efbaf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88809efbaf80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff88809efbb000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                      ^
 ffff88809efbb080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88809efbb100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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