================================================================== BUG: KASAN: slab-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:655 [inline] BUG: KASAN: slab-out-of-bounds in fb_pad_aligned_buffer+0x52f/0x5b0 drivers/video/fbdev/core/fbmem.c:115 Read of size 1 at addr ffff88805f3fdb22 by task syz-executor.5/21326 CPU: 1 PID: 21326 Comm: syz-executor.5 Not tainted 5.5.0-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+0x1fb/0x318 lib/dump_stack.c:118 print_address_description+0x74/0x5c0 mm/kasan/report.c:374 __kasan_report+0x149/0x1c0 mm/kasan/report.c:506 kasan_report+0x26/0x50 mm/kasan/common.c:639 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __fb_pad_aligned_buffer include/linux/fb.h:655 [inline] fb_pad_aligned_buffer+0x52f/0x5b0 drivers/video/fbdev/core/fbmem.c:115 bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:99 [inline] bit_putcs+0x1694/0x1cc0 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x7b4/0xad0 drivers/video/fbdev/core/fbcon.c:1353 do_update_region+0x2cb/0x600 drivers/tty/vt/vt.c:667 redraw_screen+0xcc5/0x1830 drivers/tty/vt/vt.c:1011 vc_do_resize+0x12af/0x1af0 drivers/tty/vt/vt.c:1284 vc_resize+0x4f/0x60 drivers/tty/vt/vt.c:1304 vt_ioctl+0x2fa8/0x3a70 drivers/tty/vt/vt_ioctl.c:887 tty_ioctl+0xee6/0x15c0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl fs/ioctl.c:747 [inline] __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl+0x113/0x190 fs/ioctl.c:754 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:754 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b349 Code: ad 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f22e966cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f22e966d6d4 RCX: 000000000045b349 RDX: 0000000020000000 RSI: 000000000000560a RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000666 R14: 00000000004c7ea4 R15: 000000000075bf2c Allocated by task 26912: save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc+0x118/0x1c0 mm/kasan/common.c:513 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x254/0x340 mm/slab.c:3665 kmalloc include/linux/slab.h:561 [inline] fbcon_set_font+0x2de/0x990 drivers/video/fbdev/core/fbcon.c:2663 con_font_set drivers/tty/vt/vt.c:4538 [inline] con_font_op+0xeb9/0x1620 drivers/tty/vt/vt.c:4603 vt_ioctl+0x23b7/0x3a70 drivers/tty/vt/vt_ioctl.c:965 tty_ioctl+0xee6/0x15c0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl fs/ioctl.c:747 [inline] __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl+0x113/0x190 fs/ioctl.c:754 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:754 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 19572: save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x12e/0x1e0 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10d/0x220 mm/slab.c:3757 skb_free_head net/core/skbuff.c:592 [inline] pskb_expand_head+0x385/0x1230 net/core/skbuff.c:1662 __pskb_pull_tail+0xb4/0x1330 net/core/skbuff.c:2060 pskb_may_pull include/linux/skbuff.h:2295 [inline] decode_session6 net/xfrm/xfrm_policy.c:3406 [inline] __xfrm_decode_session+0x7ac/0x28c0 net/xfrm/xfrm_policy.c:3485 xfrm_decode_session_reverse include/net/xfrm.h:1145 [inline] icmpv6_route_lookup net/ipv6/icmp.c:369 [inline] icmp6_send+0x1b69/0x2670 net/ipv6/icmp.c:569 icmpv6_send+0x12b/0x1c0 net/ipv6/ip6_icmp.c:43 ip6_pkt_drop+0x4d0/0x670 net/ipv6/route.c:4383 ip6_pkt_discard_out+0xae/0x120 net/ipv6/route.c:4396 dst_output include/net/dst.h:436 [inline] ip6_local_out+0x105/0x130 net/ipv6/output_core.c:179 ip6_send_skb+0x12b/0x230 net/ipv6/ip6_output.c:1795 ip6_push_pending_frames+0xc0/0xf0 net/ipv6/ip6_output.c:1815 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x2fe4/0x4100 net/ipv6/raw.c:956 inet_sendmsg+0x147/0x310 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] sock_write_iter+0x2ee/0x400 net/socket.c:1004 do_iter_readv_writev+0x651/0x8e0 include/linux/fs.h:1896 do_iter_write+0x180/0x590 fs/read_write.c:970 vfs_writev fs/read_write.c:1015 [inline] do_writev+0x239/0x490 fs/read_write.c:1058 __do_sys_writev fs/read_write.c:1131 [inline] __se_sys_writev fs/read_write.c:1128 [inline] __x64_sys_writev+0x7d/0x90 fs/read_write.c:1128 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88805f3fc000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6946 bytes inside of 8192-byte region [ffff88805f3fc000, ffff88805f3fe000) The buggy address belongs to the page: page:ffffea00017cff00 refcount:1 mapcount:0 mapping:ffff8880aa4021c0 index:0x0 compound_mapcount: 0 raw: 00fffe0000010200 ffffea0001894a08 ffffea0000f55308 ffff8880aa4021c0 raw: 0000000000000000 ffff88805f3fc000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805f3fda00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f3fda80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805f3fdb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805f3fdb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f3fdc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================