On Tue, 28 Nov 2017 12:45:01 -0800 syzbot <bot+73a7bec1bc0f4fc0512a246334081f8c671762a8@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzkaller hit the following crash on > b0a84f19a5161418d4360cd57603e94ed489915e > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > > Unfortunately, I don't have any reproducer for this bug yet. > > > WARNING: suspicious RCU usage There's a bunch of other info which lockdep_rcu_suspicious() should have printed out, but this trace doesn't have any of it. I wonder why. > 4.14.0-next-20171127+ #53 Not tainted > 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 1cd9be067 P4D 1cd9be067 PUD 1c646d067 PMD 0 > Oops: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 1 PID: 17319 Comm: syz-executor7 Not tainted 4.14.0-next-20171127+ #53 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > task: ffff8801c5442040 task.stack: ffff8801c7ed8000 > RIP: 0010:virt_to_cache mm/slab.c:400 [inline] > RIP: 0010:kfree+0xb2/0x250 mm/slab.c:3803 > RSP: 0018:ffff8801c7edf780 EFLAGS: 00010046 > RAX: 0000000000000000 RBX: ffff8801c7edf948 RCX: ffffffffffffffff > RDX: ffffea00071fb7c0 RSI: 0000000000000000 RDI: ffff8801c7edf948 > RBP: ffff8801c7edf7a0 R08: ffffed003b02866c R09: 0000000000000000 > R10: 0000000000000001 R11: ffffed003b02866b R12: 0000000000000286 > R13: 0000000000000000 R14: ffff8801c7edf948 R15: ffff8801c7edf8b0 > FS: 00007ff14d179700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000074 CR3: 00000001c6768000 CR4: 00000000001426e0 > 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_encrypt_blkcipher+0x213/0x310 crypto/skcipher.c:631 > crypto_skcipher_encrypt include/crypto/skcipher.h:445 [inline] > _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline] > skcipher_recvmsg+0x9e8/0xf20 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 It looks like blkcipher_walk_done() passed a bad address to kfree(). > RIP: 0033:0x4529d9 > RSP: 002b:00007ff14d178c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002f > RAX: ffffffffffffffda RBX: 0000000000758190 RCX: 00000000004529d9 > RDX: 0000000000010000 RSI: 0000000020d63fc8 RDI: 0000000000000018 > RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f2728 > R13: 00000000ffffffff R14: 00007ff14d1796d4 R15: 0000000000000000 > 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: ffff8801c7edf780 > RIP: kfree+0xb2/0x250 mm/slab.c:3803 RSP: ffff8801c7edf780 > CR2: 0000000000000074 > ---[ end trace e3c719a9c9d01886 ]--- > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@xxxxxxxxxxxxxxxx. > Please credit me with: Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> > > syzbot will keep track of this bug report. > Once a fix for this bug is committed, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
