============================= BUG: unable to handle kernel NULL pointer dereference at 000000007df3f59f IP: virt_to_cache mm/slab.c:400 [inline] IP: kfree+0xb2/0x250 mm/slab.c:3802 PGD 1d833a067 P4D 1d833a067 PUD 1cd618067 PMD 0 Oops: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 16767 Comm: syz-executor4 Not tainted 4.15.0-rc2+ #143 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: 0000000063dfe421 task.stack: 00000000903cd4e4 RIP: 0010:virt_to_cache mm/slab.c:400 [inline] RIP: 0010:kfree+0xb2/0x250 mm/slab.c:3802 RSP: 0018:ffff88019cbdf780 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff88019cbdf948 RCX: ffffffffffffffff RDX: ffffea000672f7c0 RSI: 0000000000000000 RDI: ffff88019cbdf948 RBP: ffff88019cbdf7a0 R08: ffffed003898854c R09: 0000000000000000 R10: 0000000000000001 R11: ffffed003898854b R12: 0000000000000286 R13: 0000000000000000 R14: ffff88019cbdf948 R15: ffff88019cbdf8b0 FS: 00007f9607fba700(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000074 CR3: 00000001c355a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 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 ___sys_recvmsg+0x29b/0x630 net/socket.c:2207 __sys_recvmsg+0xe2/0x210 net/socket.c:2252 SYSC_recvmsg net/socket.c:2264 [inline] SyS_recvmsg+0x2d/0x50 net/socket.c:2259 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452a39 RSP: 002b:00007f9607fb9c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 0000000000758190 RCX: 0000000000452a39 RDX: 0000000000010002 RSI: 0000000020aecfc8 RDI: 0000000000000018 RBP: 000000000000039b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f2728 R13: 00000000ffffffff R14: 00007f9607fba6d4 R15: 000000000000001d 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 c5 74 af ff 48 89 de 4c 89 ef 4c 8b 75 08 e8 06 RIP: virt_to_cache mm/slab.c:400 [inline] RSP: ffff88019cbdf780 RIP: kfree+0xb2/0x250 mm/slab.c:3802 RSP: ffff88019cbdf780 CR2: 0000000000000074 ---[ end trace c3708a26eb94f9b7 ]---