crypto: use-after-free in skcipher_sock_destruct

From: Dmitry Vyukov
Date: Wed Jan 13 2016 - 06:59:47 EST

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Hello,

The following program triggers use-after-free in skcipher_sock_destruct.
This is on upstream commit 03891f9c853d5c4473224478a1e03ea00d70ff8d +
all pending patches from
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6.git +
4 latest Herbert patches.

// autogenerated by syzkaller (http://github.com/google/syzkaller)
#include <unistd.h>
#include <sys/syscall.h>
#include <string.h>
#include <stdint.h>
#include <pthread.h>

long r[53];

void *thr(void *arg)
{
switch ((long)arg) {
case 0:
r[0] = syscall(SYS_mmap, 0x20000000ul, 0x35000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 1:
r[1] = syscall(SYS_socket, 0x26ul, 0x5ul, 0x0ul, 0, 0, 0);
break;
case 2:
r[2] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 3:
r[3] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 4:
r[4] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 5:
*(uint32_t*)0x2003521a = (uint32_t)0x2;
*(uint64_t*)0x20035000 = (uint64_t)0x77359400;
*(uint64_t*)0x20035008 = (uint64_t)0x0;
*(uint32_t*)0x20035000 = (uint32_t)0x6;
r[9] = syscall(SYS_futex, 0x2003521aul, 0x9ul, 0x1ul,
0x20035000ul, 0x20035000ul, 0x8ul);
break;
case 6:
*(uint16_t*)0x20032fa8 = (uint16_t)0x26;
memcpy((void*)0x20032faa,
"\x73\x6b\x63\x69\x70\x68\x65\x72\x00\x00\x00\x00\x00\x00", 14);
*(uint32_t*)0x20032fb8 = (uint32_t)0x8;
*(uint32_t*)0x20032fbc = (uint32_t)0x6;
memcpy((void*)0x20032fc0,
"\x73\x61\x6c\x73\x61\x32\x30\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
64);
r[15] = syscall(SYS_bind, r[1], 0x20032fa8ul, 0x58ul, 0, 0, 0);
break;
case 7:
memcpy((void*)0x2002a000,
"\xdc\x4f\x77\x67\x54\xf2\x63\xd1\xbe\x5c\x6b\xac\xa6\x65\xeb\xc1\x0f\x2f\xbd\xea\x88\x2e",
22);
r[17] = syscall(SYS_setsockopt, r[1], 0x117ul, 0x1ul,
0x2002a000ul, 0x16ul, 0);
break;
case 8:
r[18] = syscall(SYS_accept4, r[1], 0x0ul,
0x2001f000ul, 0x80800ul, 0, 0);
break;
case 9:
memcpy((void*)0x20024000,
"\x50\xf0\x53\x1d\x72\x27\x23\x70\x47\x93\x30\xee\xa4\xef\xee\x21\xa5\xce\x3d\xed\x43\xcc\x9d\xfe\x1b\x50\x16\x5c\x76\x74\xd2\xee\x56\x2a\x07\xf0\x40\x6d\xa6\xbc\x23\x47\xe2\x7d\xb4\x89\x2b\x0c\xf6\x97\x8c\x00\xbb\x36\x5e\x67\xc2\x85\xf2\xc7\x41\x51\x7a\x51\x43\x9e\xe9\xf6\x27\xf4\x00\xc8\xda\x36\x87\x22\x1b\xa8\xeb\xfd\x6a\x46\x23\xf5\x8d\x51\x2b\xe0\xf8\x8d\x3a\x50\xd0\x4a\x05\x03\x14\x15\xd5\x20\xf4\xcb\xbe\xe5\x77\x37\x09",
107);
memcpy((void*)0x20033732,
"\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
128);
r[21] = syscall(SYS_sendto, r[18], 0x20024000ul,
0x6bul, 0x8800ul, 0x20033732ul, 0x80ul);
break;
case 10:
*(uint64_t*)0x200349fb = (uint64_t)0x20034111;
*(uint32_t*)0x20034a03 = (uint32_t)0x80;
*(uint64_t*)0x20034a0b = (uint64_t)0x20034fb0;
*(uint64_t*)0x20034a13 = (uint64_t)0x5;
*(uint64_t*)0x20034a1b = (uint64_t)0x20034fdd;
*(uint64_t*)0x20034a23 = (uint64_t)0x23;
*(uint32_t*)0x20034a2b = (uint32_t)0x6;
*(uint64_t*)0x20034fb0 = (uint64_t)0x20034f56;
*(uint64_t*)0x20034fb8 = (uint64_t)0xaa;
*(uint64_t*)0x20034fc0 = (uint64_t)0x20034fd0;
*(uint64_t*)0x20034fc8 = (uint64_t)0xe9;
*(uint64_t*)0x20034fd0 = (uint64_t)0x2003450a;
*(uint64_t*)0x20034fd8 = (uint64_t)0xb7;
*(uint64_t*)0x20034fe0 = (uint64_t)0x20034f88;
*(uint64_t*)0x20034fe8 = (uint64_t)0xca;
*(uint64_t*)0x20034ff0 = (uint64_t)0x20034f6b;
*(uint64_t*)0x20034ff8 = (uint64_t)0x95;
r[39] = syscall(SYS_recvmsg, r[18], 0x200349fbul,
0x2060ul, 0, 0, 0);
break;
case 11:
r[40] = syscall(SYS_dup, r[1], 0, 0, 0, 0, 0);
break;
case 12:
r[41] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 13:
*(uint16_t*)0x20035000 = (uint16_t)0x1f;
*(uint8_t*)0x20035002 = (uint8_t)0x169;
*(uint8_t*)0x20035003 = (uint8_t)0xfffffffffffffffe;
*(uint8_t*)0x20035004 = (uint8_t)0x5;
*(uint8_t*)0x20035005 = (uint8_t)0x0;
*(uint8_t*)0x20035006 = (uint8_t)0x50df1ce5;
*(uint8_t*)0x20035007 = (uint8_t)0x57;
r[49] = syscall(SYS_bind, r[40], 0x20035000ul, 0x8ul, 0, 0, 0);
break;
case 14:
r[50] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 15:
r[51] = syscall(SYS_mmap, 0x20035000ul, 0x1000ul,
0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul);
break;
case 16:
r[52] = syscall(SYS_getpeername, r[40], 0x20035000ul,
0x20035adbul, 0, 0, 0);
break;
}
return 0;
}

int main()
{
long i;
pthread_t th[17];

srand(getpid());
memset(r, -1, sizeof(r));
for (i = 0; i < 17; i++) {
pthread_create(&th[i], 0, thr, (void*)i);
usleep(1000);
}
for (i = 0; i < 17; i++) {
pthread_create(&th[i], 0, thr, (void*)i);
if (rand()%2)
usleep(rand()%1000);
}
usleep(100000);
return 0;
}

==================================================================
BUG: KASAN: use-after-free in skcipher_sock_destruct+0x2f6/0x310 at
addr ffff880061db0270
Read of size 4 by task syz-executor/30602
=============================================================================
BUG kmalloc-128 (Not tainted): kasan: bad access detected
-----------------------------------------------------------------------------

INFO: Allocated in crypto_create_tfm+0x7e/0x240 age=38 cpu=2 pid=30612
[< none >] ___slab_alloc+0x486/0x4e0 mm/slub.c:2468
[< none >] __slab_alloc+0x66/0xc0 mm/slub.c:2497
[< inline >] slab_alloc_node mm/slub.c:2560
[< inline >] slab_alloc mm/slub.c:2602
[< none >] __kmalloc+0x2b9/0x350 mm/slub.c:3562
[< inline >] kmalloc include/linux/slab.h:463
[< inline >] kzalloc include/linux/slab.h:602
[< none >] crypto_create_tfm+0x7e/0x240 crypto/api.c:470
[< none >] crypto_alloc_tfm+0x13c/0x370 crypto/api.c:555
[< none >] crypto_alloc_skcipher+0x2c/0x40 crypto/skcipher.c:242
[< none >] skcipher_bind+0x6c/0xe0 crypto/algif_skcipher.c:858
[< none >] alg_bind+0x18e/0x430 crypto/af_alg.c:178
[< none >] SYSC_bind+0x1ea/0x250 net/socket.c:1377
[< none >] SyS_bind+0x24/0x30 net/socket.c:1363
[< none >] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185

INFO: Freed in kzfree+0x28/0x30 age=16 cpu=0 pid=30602
[< none >] __slab_free+0x1fc/0x320 mm/slub.c:2678
[< inline >] slab_free mm/slub.c:2833
[< none >] kfree+0x2a8/0x2d0 mm/slub.c:3662
[< none >] kzfree+0x28/0x30 mm/slab_common.c:1270
[< none >] crypto_destroy_tfm+0xcb/0x190 crypto/api.c:596
[< inline >] crypto_free_skcipher include/crypto/skcipher.h:215
[< none >] skcipher_release+0x30/0x50 crypto/algif_skcipher.c:873
[< inline >] alg_do_release crypto/af_alg.c:118
[< none >] alg_sock_destruct+0x8c/0xe0 crypto/af_alg.c:358
[< none >] sk_destruct+0x4a/0x490 net/core/sock.c:1447
[< none >] __sk_free+0x57/0x200 net/core/sock.c:1475
[< none >] sk_free+0x30/0x40 net/core/sock.c:1486
[< inline >] sock_put include/net/sock.h:1627
[< none >] af_alg_release+0x5b/0x70 crypto/af_alg.c:125
[< none >] sock_release+0x8d/0x1d0 net/socket.c:572
[< none >] sock_close+0x16/0x20 net/socket.c:1023
[< none >] __fput+0x236/0x780 fs/file_table.c:208
[< none >] ____fput+0x15/0x20 fs/file_table.c:244
[< none >] task_work_run+0x16b/0x200 kernel/task_work.c:115
[< inline >] exit_task_work include/linux/task_work.h:21
[< none >] do_exit+0x8be/0x2b80 kernel/exit.c:750

INFO: Slab 0xffffea0001876c00 objects=27 used=26 fp=0xffff880061db20d0
flags=0x5fffc0000004080
INFO: Object 0xffff880061db0258 @offset=600 fp=0xffffffff82746af0
CPU: 0 PID: 30602 Comm: syz-executor Tainted: G B 4.4.0+ #238
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
00000000ffffffff ffff8800341df7b0 ffffffff8290ea2d ffff88003e807300
ffff880061db0258 ffff880061db0000 ffff8800341df7e0 ffffffff81730904
ffff88003e807300 ffffea0001876c00 ffff880061db0258 0000000000000000
Call Trace:
[<ffffffff81739e1e>] __asan_report_load4_noabort+0x3e/0x40
mm/kasan/report.c:294
[< inline >] crypto_skcipher_ivsize include/crypto/skcipher.h:246
[<ffffffff828511b6>] skcipher_sock_destruct+0x2f6/0x310
crypto/algif_skcipher.c:908
[<ffffffff84d652aa>] sk_destruct+0x4a/0x490 net/core/sock.c:1447
[<ffffffff84d65747>] __sk_free+0x57/0x200 net/core/sock.c:1475
[<ffffffff84d65920>] sk_free+0x30/0x40 net/core/sock.c:1486
[< inline >] sock_put include/net/sock.h:1627
[<ffffffff8284cddb>] af_alg_release+0x5b/0x70 crypto/af_alg.c:125
[<ffffffff84d4f25d>] sock_release+0x8d/0x1d0 net/socket.c:572
[<ffffffff84d4f3b6>] sock_close+0x16/0x20 net/socket.c:1023
[<ffffffff81780cf6>] __fput+0x236/0x780 fs/file_table.c:208
[<ffffffff817812c5>] ____fput+0x15/0x20 fs/file_table.c:244
[<ffffffff8139fdab>] task_work_run+0x16b/0x200 kernel/task_work.c:115
[< inline >] exit_task_work include/linux/task_work.h:21
[<ffffffff8134bb6e>] do_exit+0x8be/0x2b80 kernel/exit.c:750
[<ffffffff8134dfa8>] do_group_exit+0x108/0x330 kernel/exit.c:880
[<ffffffff81371214>] get_signal+0x5e4/0x1500 kernel/signal.c:2307
[<ffffffff81193db3>] do_signal+0x83/0x1c90 arch/x86/kernel/signal.c:712
[<ffffffff81006685>] exit_to_usermode_loop+0x1a5/0x210
arch/x86/entry/common.c:247
[< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:282
[<ffffffff8100851a>] syscall_return_slowpath+0x2ba/0x340
arch/x86/entry/common.c:344
[<ffffffff85e8ece2>] int_ret_from_sys_call+0x25/0x9f
arch/x86/entry/entry_64.S:281
==================================================================

Next message: Kishon Vijay Abraham I: "Re: [PATCH 1/2] phy: zynqmp: Add dt bindings for ZynqMP PHY."
Previous message: Aniroop Mathur: "[PATCH] [v5]Input: evdev: fix bug of dropping full valid packet after syn_dropped"
Next in thread: Herbert Xu: "[PATCH 0/2] crypto: Fix race condition in *_check_key"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]