lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 17 Dec 2015 13:59:50 +0100
From:	Dmitry Vyukov <dvyukov@...gle.com>
To:	Herbert Xu <herbert@...dor.apana.org.au>,
	"David S. Miller" <davem@...emloft.net>,
	linux-crypto@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>
Cc:	syzkaller <syzkaller@...glegroups.com>,
	Kostya Serebryany <kcc@...gle.com>,
	Alexander Potapenko <glider@...gle.com>,
	Eric Dumazet <edumazet@...gle.com>,
	Sasha Levin <sasha.levin@...cle.com>,
	Kees Cook <keescook@...gle.com>
Subject: use-after-free in hash_sock_destruct

Hello,

The following program causes use-after-free in hash_sock_destruct:

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

struct sockaddr_alg {
        unsigned short   salg_family;
        char    salg_type[14];
        unsigned   salg_feat;
        unsigned   salg_mask;
        char    salg_name[64];
};

int fd;

void *thr0(void *arg)
{
        struct sockaddr_alg sa = {};
        sa.salg_family = 0x26;
        memcpy(sa.salg_type,
"\x68\x61\x73\x68\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 14);
        sa.salg_feat = 0xf;
        sa.salg_mask = 0x100;
        memcpy(sa.salg_name,
"\x6d\x64\x34\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",
64);
        bind(fd, (struct sockaddr*)&sa, sizeof(sa));
        return 0;
}

void *thr1(void *arg)
{
        accept4(fd, 0, 0, 0x800ul);
        return 0;
}

int main()
{
        fd = socket(PF_ALG, SOCK_SEQPACKET, 0);
        pthread_t th[4];
        pthread_create(&th[0], 0, thr0, 0);
        pthread_create(&th[1], 0, thr1, 0);
        pthread_create(&th[2], 0, thr0, 0);
        pthread_create(&th[3], 0, thr1, 0);
        pthread_join(th[0], 0);
        pthread_join(th[1], 0);
        pthread_join(th[2], 0);
        pthread_join(th[3], 0);
        return 0;
}



==================================================================
BUG: KASAN: use-after-free in hash_sock_destruct+0x1de/0x260 at addr
ffff88005f057090
Read of size 8 by task a.out/6844
=============================================================================
BUG kmalloc-192 (Not tainted): kasan: bad access detected
-----------------------------------------------------------------------------

Disabling lock debugging due to kernel taint
INFO: Allocated in crypto_create_tfm+0x87/0x2a0 age=3 cpu=2 pid=6845
[<      none      >] ___slab_alloc+0x648/0x8c0 mm/slub.c:2438
[<      none      >] __slab_alloc+0x4c/0x90 mm/slub.c:2467
[<     inline     >] slab_alloc_node mm/slub.c:2530
[<     inline     >] slab_alloc mm/slub.c:2572
[<      none      >] __kmalloc+0x2d9/0x480 mm/slub.c:3532
[<     inline     >] kmalloc include/linux/slab.h:463
[<     inline     >] kzalloc include/linux/slab.h:602
[<      none      >] crypto_create_tfm+0x87/0x2a0 crypto/api.c:470
[<      none      >] crypto_alloc_tfm+0x138/0x3f0 crypto/api.c:555
[<      none      >] crypto_alloc_ahash+0x2c/0x40 crypto/ahash.c:538
[<      none      >] hash_bind+0x25/0x30 crypto/algif_hash.c:240
[<      none      >] alg_bind+0x1a9/0x410 crypto/af_alg.c:155
[<      none      >] SYSC_bind+0x20a/0x2c0 net/socket.c:1383
[<      none      >] SyS_bind+0x24/0x30 net/socket.c:1369
[<      none      >] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185

INFO: Freed in kzfree+0x28/0x30 age=2 cpu=1 pid=6847
[<      none      >] __slab_free+0x21e/0x3e0 mm/slub.c:2648
[<     inline     >] slab_free mm/slub.c:2803
[<      none      >] kfree+0x26f/0x3e0 mm/slub.c:3632
[<      none      >] kzfree+0x28/0x30 mm/slab_common.c:1270
[<      none      >] crypto_destroy_tfm+0xdd/0x1e0 crypto/api.c:596
[<     inline     >] crypto_free_ahash include/crypto/hash.h:258
[<      none      >] hash_release+0x19/0x20 crypto/algif_hash.c:245
[<     inline     >] alg_do_release crypto/af_alg.c:116
[<      none      >] alg_bind+0x26a/0x410 crypto/af_alg.c:170
[<      none      >] SYSC_bind+0x20a/0x2c0 net/socket.c:1383
[<      none      >] SyS_bind+0x24/0x30 net/socket.c:1369
[<      none      >] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185

INFO: Slab 0xffffea00017c1580 objects=16 used=15 fp=0xffff88005f057000
flags=0x5fffc0000004080
INFO: Object 0xffff88005f057000 @offset=4096 fp=0x          (null)
CPU: 1 PID: 6844 Comm: a.out Tainted: G    B           4.4.0-rc3+ #151
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 0000000000000001 ffff8800379779e0 ffffffff82e0f4b8 0000000041b58ab3
 ffffffff87a9a265 ffffffff82e0f406 ffff88003d8c0000 ffffffff87abb3aa
 ffff88003e804a00 0000000000000008 ffff88005f057000 ffff8800379779e0

Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff82e0f4b8>] dump_stack+0xb2/0xfa lib/dump_stack.c:50
 [<ffffffff8183680c>] print_trailer+0x12c/0x210 mm/slub.c:652
 [<ffffffff8184162f>] object_err+0x2f/0x40 mm/slub.c:659
 [<     inline     >] print_address_description mm/kasan/report.c:138
 [<ffffffff81845399>] kasan_report_error+0x5d9/0x860 mm/kasan/report.c:251
 [<     inline     >] kasan_report mm/kasan/report.c:274
 [<ffffffff818457c4>] __asan_report_load8_noabort+0x54/0x70
mm/kasan/report.c:295
 [<     inline     >] crypto_ahash_digestsize include/crypto/hash.h:290
 [<ffffffff82d2a7ae>] hash_sock_destruct+0x1de/0x260 crypto/algif_hash.c:259
 [<ffffffff856c9255>] sk_destruct+0xa5/0x5f0 net/core/sock.c:1446
 [<ffffffff856c982c>] __sk_free+0x8c/0x260 net/core/sock.c:1474
 [<ffffffff856c9a30>] sk_free+0x30/0x40 net/core/sock.c:1485
 [<     inline     >] sock_put include/net/sock.h:1625
 [<ffffffff82d26c50>] af_alg_release+0x60/0x90 crypto/af_alg.c:123
 [<ffffffff856b06b6>] sock_release+0x96/0x260 net/socket.c:571
 [<ffffffff856b0896>] sock_close+0x16/0x20 net/socket.c:1022
 [<ffffffff8189d9e4>] __fput+0x244/0x860 fs/file_table.c:208
 [<ffffffff8189e095>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff813e34d0>] task_work_run+0x130/0x240 kernel/task_work.c:115
 [<     inline     >] exit_task_work include/linux/task_work.h:21
 [<ffffffff8137d8f5>] do_exit+0x885/0x3050 kernel/exit.c:750
 [<ffffffff8138021c>] do_group_exit+0xec/0x390 kernel/exit.c:880
 [<     inline     >] SYSC_exit_group kernel/exit.c:891
 [<ffffffff813804dd>] SyS_exit_group+0x1d/0x20 kernel/exit.c:889
 [<ffffffff86a89fb6>] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185
==================================================================
BUG: unable to handle kernel paging request at fffffffffffffff8
IP: [<ffffffff82d2a6ae>] hash_sock_destruct+0xde/0x260 crypto/algif_hash.c:258
PGD 7c2f067 PUD 7c31067 PMD 0
Oops: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 6844 Comm: a.out Tainted: G    B           4.4.0-rc3+ #151
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff88003d8c0000 ti: ffff880037970000 task.ti: ffff880037970000
RIP: 0010:[<ffffffff82d2a6ae>]  [<ffffffff82d2a6ae>]
hash_sock_destruct+0xde/0x260
RSP: 0018:ffff880037977b30  EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88005f94dc80 RCX: 0000000000000001
RDX: 1fffffffffffffff RSI: 0000000000000001 RDI: 0000000000000282
RBP: ffff880037977b58 R08: 0000000000000001 R09: 0000000000000000
R10: ffffed0006f2ef55 R11: 0000000000000000 R12: ffff88005f94e5c0
R13: 0000000000000000 R14: fffffffffffffff8 R15: ffffffff856b0880
FS:  0000000000000000(0000) GS:ffff88003ed00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: fffffffffffffff8 CR3: 0000000007c2e000 CR4: 00000000000006e0
Stack:
 ffff880000000000 ffff88005f94e5c0 ffffffff82d2a5d0 1ffff10006f2ef6d
 0000000000000000 ffff880037977bf0 ffffffff856c9255 0000000041b58ab3
 ffffffff87a9a273 ffffffff856c91b0 ffff8800602c8610 ffff88003d8c0000
Call Trace:
 [<ffffffff856c9255>] sk_destruct+0xa5/0x5f0 net/core/sock.c:1446
 [<ffffffff856c982c>] __sk_free+0x8c/0x260 net/core/sock.c:1474
 [<ffffffff856c9a30>] sk_free+0x30/0x40 net/core/sock.c:1485
 [<     inline     >] sock_put include/net/sock.h:1625
 [<ffffffff82d26c50>] af_alg_release+0x60/0x90 crypto/af_alg.c:123
 [<ffffffff856b06b6>] sock_release+0x96/0x260 net/socket.c:571
 [<ffffffff856b0896>] sock_close+0x16/0x20 net/socket.c:1022
 [<ffffffff8189d9e4>] __fput+0x244/0x860 fs/file_table.c:208
 [<ffffffff8189e095>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff813e34d0>] task_work_run+0x130/0x240 kernel/task_work.c:115
 [<     inline     >] exit_task_work include/linux/task_work.h:21
 [<ffffffff8137d8f5>] do_exit+0x885/0x3050 kernel/exit.c:750
 [<ffffffff8138021c>] do_group_exit+0xec/0x390 kernel/exit.c:880
 [<     inline     >] SYSC_exit_group kernel/exit.c:891
 [<ffffffff813804dd>] SyS_exit_group+0x1d/0x20 kernel/exit.c:889
 [<ffffffff86a89fb6>] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185
Code: 08 0f 84 7c 01 00 00 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48
c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e d4 00 00 00 48 85 db <41>
8b 55 f8 0f 84 35 01 00 00 48 8d bb 30 03 00 00 48 b8 00 00
RIP  [<ffffffff82d2a6ae>] hash_sock_destruct+0xde/0x260 crypto/algif_hash.c:258
 RSP <ffff880037977b30>
CR2: fffffffffffffff8
---[ end trace b367ebac5d601601 ]---
Fixing recursive fault but reboot is needed!


On upstream commit 31ade3b83e1821da5fbb2f11b5b3d4ab2ec39db8 (Nov 29).
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ