syzbot


KASAN: use-after-free Read in crypto_aead_free_instance

Status: closed as dup on 2017/12/20 22:37
Reported-by: syzbot+e5e6fab2d4dc3d9877ac240fed364027bb960ad0@syzkaller.appspotmail.com
Fix commit: d76c68109f37 crypto: pcrypt - fix freeing pcrypt instances
First crash: 1820d, last: 1811d
Duplicate of (1):
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in __list_del_entry_valid (2) C 11 1815d 1817d

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in crypto_aead_free_instance+0xc0/0xd0 crypto/aead.c:154
Read of size 8 at addr ffff8801c7fa3680 by task cryptomgr_test/14926

CPU: 0 PID: 14926 Comm: cryptomgr_test Not tainted 4.15.0-rc4+ #145
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
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 crypto_aead_free_instance+0xc0/0xd0 crypto/aead.c:154
 crypto_free_instance+0x6d/0x100 crypto/algapi.c:77
 crypto_destroy_instance+0x3c/0x80 crypto/algapi.c:85
 crypto_alg_put crypto/internal.h:116 [inline]
 crypto_remove_final+0x212/0x370 crypto/algapi.c:331
 crypto_alg_tested+0x445/0x6f0 crypto/algapi.c:320
 cryptomgr_test+0x17/0x30 crypto/algboss.c:226
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:515

Allocated by task 14922:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610
 kmalloc include/linux/slab.h:499 [inline]
 kzalloc include/linux/slab.h:688 [inline]
 pcrypt_create_aead crypto/pcrypt.c:291 [inline]
 pcrypt_create+0x137/0x6c0 crypto/pcrypt.c:346
 cryptomgr_probe+0x74/0x240 crypto/algboss.c:75
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:515

Freed by task 3150:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3488 [inline]
 kfree+0xd6/0x260 mm/slab.c:3803
 skb_free_head+0x74/0xb0 net/core/skbuff.c:550
 skb_release_data+0x58c/0x790 net/core/skbuff.c:570
 skb_release_all+0x4a/0x60 net/core/skbuff.c:627
 __kfree_skb net/core/skbuff.c:641 [inline]
 consume_skb+0x153/0x490 net/core/skbuff.c:701
 __dev_kfree_skb_any+0x85/0xa0 net/core/dev.c:2515
 dev_consume_skb_any include/linux/netdevice.h:3276 [inline]
 free_old_xmit_skbs.isra.27+0x15a/0x2c0 drivers/net/virtio_net.c:1167
 start_xmit+0x1b9/0x1650 drivers/net/virtio_net.c:1314
 __netdev_start_xmit include/linux/netdevice.h:4042 [inline]
 netdev_start_xmit include/linux/netdevice.h:4051 [inline]
 xmit_one net/core/dev.c:2991 [inline]
 dev_hard_start_xmit+0x248/0xac0 net/core/dev.c:3007
 sch_direct_xmit+0x31d/0x6d0 net/sched/sch_generic.c:187
 __dev_xmit_skb net/core/dev.c:3189 [inline]
 __dev_queue_xmit+0x16f4/0x2070 net/core/dev.c:3456
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3521
 neigh_hh_output include/net/neighbour.h:472 [inline]
 neigh_output include/net/neighbour.h:480 [inline]
 ip_finish_output2+0xece/0x1460 net/ipv4/ip_output.c:229
 ip_finish_output+0x85e/0xd10 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:239 [inline]
 ip_output+0x1cc/0x860 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:460 [inline]
 ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x8c6/0x18e0 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1b12/0x38b0 net/ipv4/tcp_output.c:1176
 tcp_write_xmit+0x680/0x5190 net/ipv4/tcp_output.c:2367
 __tcp_push_pending_frames+0xa0/0x250 net/ipv4/tcp_output.c:2543
 tcp_push+0x538/0x770 net/ipv4/tcp.c:730
 tcp_sendmsg_locked+0x2663/0x3b30 net/ipv4/tcp.c:1424
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1461
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:636 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:646
 sock_write_iter+0x31a/0x5d0 net/socket.c:915
 call_write_iter include/linux/fs.h:1772 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:482
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801c7fa3680
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 0 bytes inside of
 1024-byte region [ffff8801c7fa3680, ffff8801c7fa3a80)
The buggy address belongs to the page:
page:00000000b962d6ee count:1 mapcount:0 mapping:000000005c7f5100 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801c7fa2000 0000000000000000 0000000100000007
raw: ffffea00071f0fa0 ffffea00071ffe20 ffff8801db000ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c7fa3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c7fa3600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c7fa3680: fb fb fb fb 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff8801c7fa3700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c7fa3780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (5):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-386 2017/12/23 13:18 upstream 9c294ec08408 73aba437 .config log report syz C
ci-upstream-kasan-gce-386 2017/12/15 22:58 upstream 032b4cc8ff84 ac20b98c .config log report syz C
ci-upstream-net-kasan-gce 2017/12/23 11:46 net-next fba961ab29e5 73aba437 .config log report syz C
ci-upstream-mmots-kasan-gce 2017/12/24 06:14 mmots 37759fa6d0fa 73aba437 .config log report syz C
ci-upstream-mmots-kasan-gce 2017/12/15 20:59 mmots 82bcf1def3b5 ac20b98c .config log report syz C
* Struck through repros no longer work on HEAD.