input: syz1 as /devices/virtual/input/input16 ================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:663 [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+0xa8a/0xc00 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff8880a11051d0 by task syz-executor.1/30490 CPU: 1 PID: 30490 Comm: syz-executor.1 Not tainted 4.14.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xa8a/0xc00 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x3bb/0x480 drivers/video/fbdev/core/fbcon.c:1301 do_update_region+0x282/0x5b0 drivers/tty/vt/vt.c:363 redraw_screen+0x562/0x760 drivers/tty/vt/vt.c:705 vc_do_resize+0xbe0/0xde0 drivers/tty/vt/vt.c:967 vt_ioctl+0x1a64/0x1f20 drivers/tty/vt/vt_ioctl.c:901 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45cb19 RSP: 002b:00007feff34a3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004f35c0 RCX: 000000000045cb19 RDX: 0000000020000000 RSI: 000000000000560a RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000067f R14: 00000000004c9859 R15: 00007feff34a46d4 Allocated by task 9550: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.0+0x4f/0xd0 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] fbcon_set_font+0x2f8/0x7c0 drivers/video/fbdev/core/fbcon.c:2621 con_font_set drivers/tty/vt/vt.c:4182 [inline] con_font_op+0xb73/0xf70 drivers/tty/vt/vt.c:4247 vt_ioctl+0x736/0x1f20 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 17: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcb/0x260 mm/slab.c:3815 skb_free_head+0x83/0xa0 net/core/skbuff.c:554 skb_release_data+0x57e/0x7d0 net/core/skbuff.c:574 skb_release_all+0x46/0x60 net/core/skbuff.c:631 __kfree_skb net/core/skbuff.c:645 [inline] kfree_skb+0xae/0x340 net/core/skbuff.c:663 ip6_mc_input+0x74e/0x9e0 net/ipv6/ip6_input.c:417 dst_input include/net/dst.h:468 [inline] ip6_rcv_finish+0x23b/0x7a0 net/ipv6/ip6_input.c:71 NF_HOOK include/linux/netfilter.h:250 [inline] ipv6_rcv+0xbfe/0x1c80 net/ipv6/ip6_input.c:218 __netif_receive_skb_core+0x1e8e/0x2c10 net/core/dev.c:4478 __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4516 process_backlog+0x20c/0x760 net/core/dev.c:5198 napi_poll net/core/dev.c:5599 [inline] net_rx_action+0x456/0xe80 net/core/dev.c:5665 __do_softirq+0x254/0x9bf kernel/softirq.c:288 The buggy address belongs to the object at ffff8880a11050c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 272 bytes inside of 512-byte region [ffff8880a11050c0, ffff8880a11052c0) The buggy address belongs to the page: page:ffffea0002844140 count:1 mapcount:0 mapping:ffff8880a11050c0 index:0xffff8880a11055c0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffff8880a11050c0 ffff8880a11055c0 0000000100000002 raw: ffffea000294a4e0 ffffea0002277120 ffff8880aa800940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a1105080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8880a1105100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a1105180: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff8880a1105200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a1105280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================