============================= WARNING: suspicious RCU usage 4.14.0-next-20171127+ #52 Not tainted ----------------------------- ./include/trace/events/kmem.h:142 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor3/18382: #0: (sk_lock-AF_ALG){+.+.}, at: [] lock_sock include/net/sock.h:1467 [inline] #0: (sk_lock-AF_ALG){+.+.}, at: [] af_alg_wait_for_data+0x2f2/0x650 crypto/af_alg.c:768 stack backtrace: CPU: 1 PID: 18382 Comm: syz-executor3 Not tainted 4.14.0-next-20171127+ #52 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4675 trace_kfree include/trace/events/kmem.h:137 [inline] kfree+0x20a/0x250 mm/slab.c:3797 blkcipher_walk_done+0x72b/0xde0 crypto/blkcipher.c:139 encrypt+0x50a/0xaf0 crypto/salsa20_generic.c:208 skcipher_crypt_blkcipher crypto/skcipher.c:622 [inline] skcipher_decrypt_blkcipher+0x213/0x310 crypto/skcipher.c:640 crypto_skcipher_decrypt include/crypto/skcipher.h:463 [inline] _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline] skcipher_recvmsg+0xa54/0xf20 crypto/algif_skcipher.c:165 sock_recvmsg_nosec net/socket.c:805 [inline] sock_recvmsg+0xc9/0x110 net/socket.c:812 sock_read_iter+0x361/0x560 net/socket.c:889 call_read_iter include/linux/fs.h:1766 [inline] do_iter_readv_writev+0x607/0x7f0 fs/read_write.c:651 do_iter_read+0x220/0x5b0 fs/read_write.c:895 vfs_readv+0x121/0x1c0 fs/read_write.c:959 do_readv+0xfc/0x2a0 fs/read_write.c:992 SYSC_readv fs/read_write.c:1079 [inline] SyS_readv+0x27/0x30 fs/read_write.c:1076 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x4529d9 RSP: 002b:00007fc6e9528c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 00000000004529d9 RDX: 0000000000000002 RSI: 0000000020f3f000 RDI: 0000000000000015 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f26b0 R13: 00000000ffffffff R14: 00007fc6e95296d4 R15: 0000000000000009 BUG: unable to handle kernel NULL pointer dereference at 0000000000000074 IP: virt_to_cache mm/slab.c:400 [inline] IP: kfree+0xb2/0x250 mm/slab.c:3803 PGD 1d52ea067 P4D 1d52ea067 PUD 1cba59067 PMD 0 Oops: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 18382 Comm: syz-executor3 Not tainted 4.14.0-next-20171127+ #52 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801c3d1c380 task.stack: ffff8801c8448000 RIP: 0010:virt_to_cache mm/slab.c:400 [inline] RIP: 0010:kfree+0xb2/0x250 mm/slab.c:3803 RSP: 0018:ffff8801c844f660 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff8801c844f828 RCX: ffffffffffffffff RDX: ffffea00072113c0 RSI: 0000000000000000 RDI: ffff8801c844f828 RBP: ffff8801c844f680 R08: 1ffff10039089e7e R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000286 R13: 0000000000000000 R14: ffff8801c844f828 R15: ffff8801c844f790 FS: 00007fc6e9529700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000074 CR3: 0000000192fde000 CR4: 00000000001426e0 DR0: 0000000020000000 DR1: 0000000020001000 DR2: 0000000020000000 DR3: 0000000020000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: blkcipher_walk_done+0x72b/0xde0 crypto/blkcipher.c:139 encrypt+0x50a/0xaf0 crypto/salsa20_generic.c:208 skcipher_crypt_blkcipher crypto/skcipher.c:622 [inline] skcipher_decrypt_blkcipher+0x213/0x310 crypto/skcipher.c:640 crypto_skcipher_decrypt include/crypto/skcipher.h:463 [inline] _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline] skcipher_recvmsg+0xa54/0xf20 crypto/algif_skcipher.c:165 sock_recvmsg_nosec net/socket.c:805 [inline] sock_recvmsg+0xc9/0x110 net/socket.c:812 sock_read_iter+0x361/0x560 net/socket.c:889 call_read_iter include/linux/fs.h:1766 [inline] do_iter_readv_writev+0x607/0x7f0 fs/read_write.c:651 do_iter_read+0x220/0x5b0 fs/read_write.c:895 vfs_readv+0x121/0x1c0 fs/read_write.c:959 do_readv+0xfc/0x2a0 fs/read_write.c:992 SYSC_readv fs/read_write.c:1079 [inline] SyS_readv+0x27/0x30 fs/read_write.c:1076 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x4529d9 RSP: 002b:00007fc6e9528c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 00000000004529d9 RDX: 0000000000000002 RSI: 0000000020f3f000 RDI: 0000000000000015 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f26b0 R13: 00000000ffffffff R14: 00007fc6e95296d4 R15: 0000000000000009 Code: c2 48 b8 00 00 00 00 00 ea ff ff 48 89 df 48 c1 ea 0c 48 c1 e2 06 48 01 c2 48 8b 42 20 48 8d 48 ff a8 01 48 0f 45 d1 4c 8b 6a 30 <49> 63 75 74 e8 b5 5c af ff 48 89 de 4c 89 ef 4c 8b 75 08 e8 76 RIP: virt_to_cache mm/slab.c:400 [inline] RSP: ffff8801c844f660 RIP: kfree+0xb2/0x250 mm/slab.c:3803 RSP: ffff8801c844f660 CR2: 0000000000000074 ---[ end trace 74a0c0f7f4a05919 ]---