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BUG: KASAN: use-after-free in _aead_recvmsg crypto/algif_aead.c:297 [inline]
BUG: KASAN: use-after-free in aead_recvmsg+0x1827/0x1bc0 crypto/algif_aead.c:329
Write of size 4 at addr ffff880193088374 by task syz-executor1/3589

CPU: 0 PID: 3589 Comm: syz-executor1 Not tainted 4.15.0-rc1-mm1+ #29
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_store4_noabort+0x17/0x20 mm/kasan/report.c:434
 _aead_recvmsg crypto/algif_aead.c:297 [inline]
 aead_recvmsg+0x1827/0x1bc0 crypto/algif_aead.c:329
 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]
 aio_read+0x2b0/0x3a0 fs/aio.c:1501
 io_submit_one fs/aio.c:1611 [inline]
 do_io_submit+0xf99/0x14f0 fs/aio.c:1682
 SYSC_io_submit fs/aio.c:1707 [inline]
 SyS_io_submit+0x27/0x30 fs/aio.c:1704
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4529d9
RSP: 002b:00007feb8645cc58 EFLAGS: 00000212 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 00000000004529d9
RDX: 0000000020738000 RSI: 0000000000000001 RDI: 00007feb8641b000
RBP: 000000000000015d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ef158
R13: 00000000ffffffff R14: 00007feb8645d6d4 R15: 0000000000000004

Allocated by task 3589:
 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
 __do_kmalloc mm/slab.c:3712 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3721
 kmalloc include/linux/slab.h:519 [inline]
 sock_kmalloc+0x112/0x190 net/core/sock.c:1979
 af_alg_alloc_areq+0x74/0x2f0 crypto/af_alg.c:1095
 _aead_recvmsg crypto/algif_aead.c:152 [inline]
 aead_recvmsg+0x443/0x1bc0 crypto/algif_aead.c:329
 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]
 aio_read+0x2b0/0x3a0 fs/aio.c:1501
 io_submit_one fs/aio.c:1611 [inline]
 do_io_submit+0xf99/0x14f0 fs/aio.c:1682
 SYSC_io_submit fs/aio.c:1707 [inline]
 SyS_io_submit+0x27/0x30 fs/aio.c:1704
 entry_SYSCALL_64_fastpath+0x1f/0x96

Freed by task 1407:
 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:3492 [inline]
 kfree+0xca/0x250 mm/slab.c:3807
 __sock_kfree_s net/core/sock.c:2000 [inline]
 sock_kfree_s+0x29/0x60 net/core/sock.c:2006
 af_alg_free_resources+0x6b/0x80 crypto/af_alg.c:1031
 af_alg_async_cb+0xbc/0x160 crypto/af_alg.c:1054
 aead_request_complete include/crypto/internal/aead.h:75 [inline]
 pcrypt_aead_serial+0x75/0xa0 crypto/pcrypt.c:123
 padata_serial_worker+0x476/0x750 kernel/padata.c:348
 process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113
 worker_thread+0x223/0x1990 kernel/workqueue.c:2247
 kthread+0x37a/0x440 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:517

The buggy address belongs to the object at ffff880193088080
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 756 bytes inside of
 2048-byte region [ffff880193088080, ffff880193088880)
The buggy address belongs to the page:
page:000000002f1ff843 count:1 mapcount:0 mapping:00000000a5665a2b index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff880193088080 0000000000000000 0000000100000003
raw: ffffea00070ae820 ffffea00064c22a0 ffff8801db000c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880193088200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880193088280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff880193088300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff880193088380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880193088400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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