================================================================== BUG: KASAN: slab-out-of-bounds in bpf_skb_proto_xlat net/core/filter.c:2151 [inline] BUG: KASAN: slab-out-of-bounds in ____bpf_skb_change_proto net/core/filter.c:2189 [inline] BUG: KASAN: slab-out-of-bounds in bpf_skb_change_proto+0xcc2/0x1080 net/core/filter.c:2164 Read of size 2 at addr ffff8881c7b11278 by task syz-executor.2/8847 CPU: 0 PID: 8847 Comm: syz-executor.2 Not tainted 4.14.154+ #0 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xe5/0x154 lib/dump_stack.c:58 print_address_description+0x60/0x226 mm/kasan/report.c:187 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316 bpf_skb_proto_xlat net/core/filter.c:2151 [inline] ____bpf_skb_change_proto net/core/filter.c:2189 [inline] bpf_skb_change_proto+0xcc2/0x1080 net/core/filter.c:2164 ___bpf_prog_run+0x2478/0x5510 kernel/bpf/core.c:1095 Allocated by task 8819: save_stack mm/kasan/common.c:76 [inline] set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc.part.0+0x53/0xc0 mm/kasan/common.c:501 slab_post_alloc_hook mm/slab.h:439 [inline] slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2800 [inline] kmem_cache_alloc+0xee/0x360 mm/slub.c:2805 kmem_cache_alloc_node include/linux/slab.h:361 [inline] __alloc_skb+0xea/0x5c0 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:980 [inline] alloc_skb_with_frags+0x85/0x500 net/core/skbuff.c:5228 sock_alloc_send_pskb+0x5c9/0x720 net/core/sock.c:2078 unix_dgram_sendmsg+0x345/0xeb0 net/unix/af_unix.c:1691 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb7/0x100 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1de/0x2f0 net/socket.c:1731 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 0xffffffffffffffff Freed by task 190: save_stack mm/kasan/common.c:76 [inline] set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x164/0x210 mm/kasan/common.c:463 slab_free_hook mm/slub.c:1407 [inline] slab_free_freelist_hook mm/slub.c:1458 [inline] slab_free mm/slub.c:3039 [inline] kmem_cache_free+0xd7/0x3b0 mm/slub.c:3055 kfree_skbmem net/core/skbuff.c:586 [inline] kfree_skbmem+0xa0/0x110 net/core/skbuff.c:580 __kfree_skb net/core/skbuff.c:646 [inline] consume_skb+0xe4/0x360 net/core/skbuff.c:705 skb_free_datagram+0x16/0xe0 net/core/datagram.c:331 unix_dgram_recvmsg+0x738/0xd00 net/unix/af_unix.c:2193 sock_recvmsg_nosec net/socket.c:819 [inline] sock_recvmsg net/socket.c:826 [inline] sock_recvmsg+0xc2/0x100 net/socket.c:822 SYSC_recvfrom net/socket.c:1815 [inline] SyS_recvfrom+0x1a8/0x2e0 net/socket.c:1787 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 0xffffffffffffffff The buggy address belongs to the object at ffff8881c7b11140 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 88 bytes to the right of 224-byte region [ffff8881c7b11140, ffff8881c7b11220) The buggy address belongs to the page: page:ffffea00071ec440 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000200(slab) raw: 4000000000000200 0000000000000000 0000000000000000 00000001800c000c raw: 0000000000000000 0000000100000001 ffff8881dab70200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881c7b11100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8881c7b11180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881c7b11200: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881c7b11280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881c7b11300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================