================================================================== BUG: KASAN: use-after-free in eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:283 Read of size 2 at addr ffff888023c0dc0b by task syz-executor.2/21217 CPU: 0 PID: 21217 Comm: syz-executor.2 Not tainted 5.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:283 dev_parse_header_protocol include/linux/netdevice.h:3264 [inline] virtio_net_hdr_to_skb.constprop.0+0x99d/0xcd0 include/linux/virtio_net.h:83 packet_snd net/packet/af_packet.c:2994 [inline] packet_sendmsg+0x233c/0x5300 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae 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:00007f4209b4f188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000000000006 RBP: 00000000004bfbb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd4a65eeef R14: 00007f4209b4f300 R15: 0000000000022000 Allocated by task 16863: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:427 [inline] ____kasan_kmalloc mm/kasan/common.c:506 [inline] ____kasan_kmalloc mm/kasan/common.c:465 [inline] __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:684 [inline] kernfs_fop_open+0x2c5/0xd40 fs/kernfs/file.c:628 do_dentry_open+0x4b9/0x11b0 fs/open.c:826 do_open fs/namei.c:3365 [inline] path_openat+0x1c0e/0x27e0 fs/namei.c:3498 do_filp_open+0x17e/0x3c0 fs/namei.c:3525 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_open fs/open.c:1211 [inline] __se_sys_open fs/open.c:1207 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1207 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888023c0dc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 11 bytes inside of 512-byte region [ffff888023c0dc00, ffff888023c0de00) The buggy address belongs to the page: page:ffffea00008f0300 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888023c0f000 pfn:0x23c0c head:ffffea00008f0300 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head) raw: 00fff00000010200 ffffea0000612308 ffffea0000be5f08 ffff888010841c80 raw: ffff888023c0f000 0000000000100007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888023c0db00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888023c0db80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888023c0dc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888023c0dc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023c0dd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================