================================================================== 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 ffff888093709e7a by task syz-executor.4/9028 CPU: 0 PID: 9028 Comm: syz-executor.4 Not tainted 4.19.190-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:2688 fbcon_set_all_vcs+0x4d9/0x620 drivers/video/fbdev/core/fbcon.c:2724 fbcon_event_notify+0x1025/0x1d80 drivers/video/fbdev/core/fbcon.c:3064 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: 0033:0x4665f9 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:00007f9a733b9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd5f4a7dbf R14: 00007f9a733b9300 R15: 0000000000022000 Allocated by task 27869: __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:2482 con_font_set drivers/tty/vt/vt.c:4537 [inline] con_font_op+0x94b/0xf20 drivers/tty/vt/vt.c:4581 vt_ioctl+0x1543/0x2380 drivers/tty/vt/vt_ioctl.c:990 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 13820: __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 __dev_kfree_skb_any+0x9c/0xc0 net/core/dev.c:2796 dev_consume_skb_any include/linux/netdevice.h:3567 [inline] napi_consume_skb+0x45d/0x5e0 net/core/skbuff.c:778 free_old_xmit_skbs+0xea/0x270 drivers/net/virtio_net.c:1391 start_xmit+0x156/0x17a0 drivers/net/virtio_net.c:1587 __netdev_start_xmit include/linux/netdevice.h:4345 [inline] netdev_start_xmit include/linux/netdevice.h:4359 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 sch_direct_xmit+0x2d6/0xf50 net/sched/sch_generic.c:332 qdisc_restart net/sched/sch_generic.c:395 [inline] __qdisc_run+0x4d0/0x1640 net/sched/sch_generic.c:403 qdisc_run include/net/pkt_sched.h:120 [inline] __dev_xmit_skb net/core/dev.c:3451 [inline] __dev_queue_xmit+0x2102/0x2e00 net/core/dev.c:3807 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip_finish_output2+0xb6d/0x15a0 net/ipv4/ip_output.c:230 ip_finish_output+0x858/0xd20 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x203/0x5f0 net/ipv4/ip_output.c:406 dst_output include/net/dst.h:455 [inline] ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x866/0x1b50 net/ipv4/ip_output.c:506 __tcp_transmit_skb+0x1bb2/0x33f0 net/ipv4/tcp_output.c:1148 __tcp_send_ack.part.0+0x3d9/0x5c0 net/ipv4/tcp_output.c:3643 __tcp_send_ack net/ipv4/tcp_output.c:3649 [inline] tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3649 __tcp_ack_snd_check+0x152/0x890 net/ipv4/tcp_input.c:5209 tcp_rcv_established+0x17fa/0x1ea0 net/ipv4/tcp_input.c:5642 tcp_v4_do_rcv+0x5d6/0x870 net/ipv4/tcp_ipv4.c:1547 tcp_v4_rcv+0x2c03/0x3b80 net/ipv4/tcp_ipv4.c:1832 ip_local_deliver_finish+0x495/0xc00 net/ipv4/ip_input.c:215 NF_HOOK include/linux/netfilter.h:289 [inline] ip_local_deliver+0x188/0x500 net/ipv4/ip_input.c:256 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x1ca/0x2e0 net/ipv4/ip_input.c:414 NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0xca/0x3c0 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:4954 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066 netif_receive_skb_internal+0xf0/0x3f0 net/core/dev.c:5156 napi_skb_finish net/core/dev.c:5600 [inline] napi_gro_receive+0x2e6/0x450 net/core/dev.c:5631 receive_buf+0xb8c/0x65c0 drivers/net/virtio_net.c:1084 virtnet_receive drivers/net/virtio_net.c:1348 [inline] virtnet_poll+0x568/0xd70 drivers/net/virtio_net.c:1453 napi_poll net/core/dev.c:6272 [inline] net_rx_action+0x4ac/0xfb0 net/core/dev.c:6338 __do_softirq+0x265/0x980 kernel/softirq.c:292 The buggy address belongs to the object at ffff888093709b40 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 826 bytes inside of 1024-byte region [ffff888093709b40, ffff888093709f40) The buggy address belongs to the page: page:ffffea00024dc200 count:1 mapcount:0 mapping:ffff88813bff0ac0 index:0xffff888093708040 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0002a46c08 ffffea0001470208 ffff88813bff0ac0 raw: ffff888093708040 ffff888093708040 0000000100000005 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888093709d00: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff888093709d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888093709e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888093709e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888093709f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================