device syz0 entered promiscuous mode ================================================================== BUG: KASAN: slab-out-of-bounds in __tcp_hdrlen include/linux/tcp.h:35 [inline] BUG: KASAN: slab-out-of-bounds in tcp_hdrlen include/linux/tcp.h:40 [inline] BUG: KASAN: slab-out-of-bounds in qdisc_pkt_len_init net/core/dev.c:3087 [inline] BUG: KASAN: slab-out-of-bounds in __dev_queue_xmit+0x1db6/0x1e60 net/core/dev.c:3369 Read of size 2 at addr ffff8801c7db4d60 by task syzkaller947126/3331 CPU: 1 PID: 3331 Comm: syzkaller947126 Not tainted 4.9.73-gf3f3457 #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801c7fc76f0 ffffffff81d922b9 ffffea00071f6d00 ffff8801c7db4d60 0000000000000000 ffff8801c7db4d60 0000000000000005 ffff8801c7fc7728 ffffffff8153bab3 ffff8801c7db4d60 0000000000000002 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x73/0x280 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report+0x275/0x360 mm/kasan/report.c:408 [] __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:427 [] __tcp_hdrlen include/linux/tcp.h:35 [inline] [] tcp_hdrlen include/linux/tcp.h:40 [inline] [] qdisc_pkt_len_init net/core/dev.c:3087 [inline] [] __dev_queue_xmit+0x1db6/0x1e60 net/core/dev.c:3369 [] ? 0xffffffff810002b8 [] dev_queue_xmit+0x17/0x20 net/core/dev.c:3458 [] packet_snd net/packet/af_packet.c:2953 [inline] [] packet_sendmsg+0x2ccc/0x4760 net/packet/af_packet.c:2978 [] sock_sendmsg_nosec net/socket.c:635 [inline] [] sock_sendmsg+0xca/0x110 net/socket.c:645 [] sock_write_iter+0x226/0x3b0 net/socket.c:843 [] new_sync_write fs/read_write.c:499 [inline] [] __vfs_write+0x4bf/0x680 fs/read_write.c:512 [] vfs_write+0x189/0x530 fs/read_write.c:560 [] SYSC_write fs/read_write.c:607 [inline] [] SyS_write+0xd9/0x1b0 fs/read_write.c:599 [] entry_SYSCALL_64_fastpath+0x23/0xc6 Allocated by task 3331: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:609 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547 slab_post_alloc_hook mm/slab.h:417 [inline] slab_alloc_node mm/slub.c:2715 [inline] slab_alloc mm/slub.c:2723 [inline] __kmalloc_track_caller+0xda/0x2b0 mm/slub.c:4232 __kmalloc_reserve.isra.37+0x33/0xc0 net/core/skbuff.c:138 __alloc_skb+0x119/0x600 net/core/skbuff.c:231 alloc_skb include/linux/skbuff.h:919 [inline] alloc_skb_with_frags+0xac/0x4f0 net/core/skbuff.c:4653 sock_alloc_send_pskb+0x5ad/0x740 net/core/sock.c:1893 packet_alloc_skb net/packet/af_packet.c:2810 [inline] packet_snd net/packet/af_packet.c:2901 [inline] packet_sendmsg+0x18a1/0x4760 net/packet/af_packet.c:2978 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xca/0x110 net/socket.c:645 sock_write_iter+0x226/0x3b0 net/socket.c:843 new_sync_write fs/read_write.c:499 [inline] __vfs_write+0x4bf/0x680 fs/read_write.c:512 vfs_write+0x189/0x530 fs/read_write.c:560 SYSC_write fs/read_write.c:607 [inline] SyS_write+0xd9/0x1b0 fs/read_write.c:599 entry_SYSCALL_64_fastpath+0x23/0xc6 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801c7db4900 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 96 bytes to the right of 1024-byte region [ffff8801c7db4900, ffff8801c7db4d00) The buggy address belongs to the page: page:ffffea00071f6d00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x8000000000004080(slab|head) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c7db4c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801c7db4c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801c7db4d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801c7db4d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801c7db4e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================