audit: type=1804 audit(1675062616.428:222): pid=20780 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.1" name="/root/syzkaller-testdir3634328975/syzkaller.se0kmN/88/bus" dev="sda1" ino=15293 res=1 netlink: 20 bytes leftover after parsing attributes in process `syz-executor.4'. ================================================================== BUG: KASAN: slab-out-of-bounds in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] BUG: KASAN: slab-out-of-bounds in refcount_read include/linux/refcount.h:43 [inline] BUG: KASAN: slab-out-of-bounds in skb_unref include/linux/skbuff.h:967 [inline] BUG: KASAN: slab-out-of-bounds in kfree_skb+0x32/0x3d0 net/core/skbuff.c:668 Read of size 4 at addr ffff8880a9f03cf4 by task syz-executor.4/20783 CPU: 0 PID: 20783 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 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+0x8f/0xa0 mm/kasan/report.c:412 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] refcount_read include/linux/refcount.h:43 [inline] skb_unref include/linux/skbuff.h:967 [inline] kfree_skb+0x32/0x3d0 net/core/skbuff.c:668 napi_free_frags include/linux/netdevice.h:3586 [inline] netif_napi_del+0x178/0x380 net/core/dev.c:6254 free_netdev+0x21f/0x410 net/core/dev.c:9250 netdev_run_todo+0x89b/0xab0 net/core/dev.c:9002 rtnl_unlock net/core/rtnetlink.c:117 [inline] rtnetlink_rcv_msg+0x460/0xb80 net/core/rtnetlink.c:4783 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline] netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fa7b87c80c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa7b6d3a168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa7b88e7f80 RCX: 00007fa7b87c80c9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000005 RBP: 00007fa7b8823ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff9620579f R14: 00007fa7b6d3a300 R15: 0000000000022000 Allocated by task 8141: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kmalloc_array include/linux/slab.h:636 [inline] netdev_create_hash net/core/dev.c:9573 [inline] netdev_init+0xaf/0x310 net/core/dev.c:9590 ops_init+0xb3/0x410 net/core/net_namespace.c:129 setup_net+0x2c2/0x720 net/core/net_namespace.c:316 copy_net_ns+0x1f7/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542 __do_sys_unshare kernel/fork.c:2610 [inline] __se_sys_unshare kernel/fork.c:2608 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8880a9f03480 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 116 bytes to the right of 2048-byte region [ffff8880a9f03480, ffff8880a9f03c80) The buggy address belongs to the page: page:ffffea0002a7c080 count:1 mapcount:0 mapping:ffff88813bff0c40 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00027ab508 ffffea0002a8d888 ffff88813bff0c40 raw: 0000000000000000 ffff8880a9f02380 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a9f03b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a9f03c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a9f03c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a9f03d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a9f03d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== audit: type=1804 audit(1675062617.138:223): pid=20801 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.1" name="/root/syzkaller-testdir3634328975/syzkaller.se0kmN/88/bus" dev="sda1" ino=15293 res=1