random: sshd: uninitialized urandom read (32 bytes read) audit: type=1400 audit(1538537154.149:7): avc: denied { map } for pid=1794 comm="syz-executor525" path="/root/syz-executor525565252" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 audit: type=1400 audit(1538537154.169:8): avc: denied { prog_load } for pid=1794 comm="syz-executor525" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=bpf permissive=1 audit: type=1400 audit(1538537154.199:9): avc: denied { prog_run } for pid=1794 comm="syz-executor525" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=bpf permissive=1 ================================================================== BUG: KASAN: slab-out-of-bounds in skb_at_tc_ingress include/net/sch_generic.h:452 [inline] BUG: KASAN: slab-out-of-bounds in bpf_push_mac_rcsum net/core/filter.c:1422 [inline] BUG: KASAN: slab-out-of-bounds in ____bpf_skb_vlan_push net/core/filter.c:1969 [inline] BUG: KASAN: slab-out-of-bounds in bpf_skb_vlan_push+0x45e/0x540 net/core/filter.c:1960 Read of size 4 at addr ffff8801d0ef0c48 by task syz-executor525/1794 CPU: 1 PID: 1794 Comm: syz-executor525 Not tainted 4.14.73+ #14 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 print_address_description+0x60/0x22b mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409 skb_at_tc_ingress include/net/sch_generic.h:452 [inline] bpf_push_mac_rcsum net/core/filter.c:1422 [inline] ____bpf_skb_vlan_push net/core/filter.c:1969 [inline] bpf_skb_vlan_push+0x45e/0x540 net/core/filter.c:1960 ___bpf_prog_run+0x248e/0x5c70 kernel/bpf/core.c:1012 Allocated by task 230: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc_node mm/slub.c:2723 [inline] slab_alloc mm/slub.c:2731 [inline] kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736 kmem_cache_alloc_node include/linux/slab.h:361 [inline] __alloc_skb+0xd8/0x550 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:980 [inline] alloc_skb_with_frags+0xab/0x500 net/core/skbuff.c:5167 sock_alloc_send_pskb+0x55e/0x6e0 net/core/sock.c:2075 unix_dgram_sendmsg+0x37b/0xf50 net/unix/af_unix.c:1681 sock_sendmsg_nosec net/socket.c:645 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:655 SYSC_sendto net/socket.c:1762 [inline] SyS_sendto+0x211/0x340 net/socket.c:1730 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 191: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:524 slab_free_hook mm/slub.c:1389 [inline] slab_free_freelist_hook mm/slub.c:1410 [inline] slab_free mm/slub.c:2966 [inline] kmem_cache_free+0x12d/0x350 mm/slub.c:2988 kfree_skbmem+0x9e/0x100 net/core/skbuff.c:582 __kfree_skb net/core/skbuff.c:642 [inline] consume_skb+0xc9/0x330 net/core/skbuff.c:701 skb_free_datagram+0x15/0xd0 net/core/datagram.c:331 unix_dgram_recvmsg+0x762/0xd20 net/unix/af_unix.c:2183 sock_recvmsg_nosec net/socket.c:818 [inline] sock_recvmsg+0xc0/0x100 net/socket.c:825 SYSC_recvfrom net/socket.c:1814 [inline] SyS_recvfrom+0x1d2/0x310 net/socket.c:1786 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff8801d0ef0b40 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 40 bytes to the right of 224-byte region [ffff8801d0ef0b40, ffff8801d0ef0c20) The buggy address belongs to the page: page:ffffea000743bc00 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000100(slab) raw: 4000000000000100 0000000000000000 0000000000000000 00000001800c000c raw: 0000000000000000 0000000100000001 ffff8801dab70200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d0ef0b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801d0ef0b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d0ef0c00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801d0ef0c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d0ef0d00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================