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WARNING: refcount bug in nfnetlink_rcv_batch

Status: closed as invalid on 2023/03/21 17:14
Subsystems: netfilter
[Documentation on labels]
First crash: 727d, last: 727d

Sample crash report:
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 32495 at lib/refcount.c:28 refcount_warn_saturate+0x107/0x1f0 lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 32495 Comm: syz-executor.2 Not tainted 6.2.0-rc6-next-20230201-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:refcount_warn_saturate+0x107/0x1f0 lib/refcount.c:28
Code: 1d 16 e4 45 0a 31 ff 89 de e8 05 50 6b fd 84 db 75 a3 e8 ec 53 6b fd 48 c7 c7 00 ba a6 8a c6 05 f6 e3 45 0a 01 e8 99 e9 32 fd <0f> 0b eb 87 e8 d0 53 6b fd 0f b6 1d df e3 45 0a 31 ff 89 de e8 d0
RSP: 0018:ffffc9000cdaf498 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc9001314a000
RDX: 0000000000040000 RSI: ffffffff814c6217 RDI: 0000000000000001
RBP: ffff88804f4360e4 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002
R13: ffff88804f4360e4 R14: dead000000000100 R15: ffffc9000cdaf5c0
FS:  00007f93c06ce700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcfc2accc8 CR3: 000000007cd6e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_sub_and_test include/linux/refcount.h:283 [inline]
 __refcount_dec_and_test include/linux/refcount.h:315 [inline]
 refcount_dec_and_test include/linux/refcount.h:333 [inline]
 skb_unref include/linux/skbuff.h:1198 [inline]
 skb_unref include/linux/skbuff.h:1192 [inline]
 __kfree_skb_reason net/core/skbuff.c:937 [inline]
 kfree_skb_reason+0x1ab/0x1e0 net/core/skbuff.c:961
 kfree_skb include/linux/skbuff.h:1213 [inline]
 nfnetlink_rcv_batch+0x14d4/0x2420 net/netfilter/nfnetlink.c:596
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline]
 nfnetlink_rcv+0x3b3/0x420 net/netfilter/nfnetlink.c:657
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942
 sock_sendmsg_nosec net/socket.c:722 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:745
 ____sys_sendmsg+0x71c/0x900 net/socket.c:2501
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555
 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f93bf88c0c9
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:00007f93c06ce168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f93bf9abf80 RCX: 00007f93bf88c0c9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f93bf8e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff8afbedef R14: 00007f93c06ce300 R15: 0000000000022000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/01 07:09 linux-next 66eee64b2354 9dfcf09c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: refcount bug in nfnetlink_rcv_batch
* Struck through repros no longer work on HEAD.