All of lore.kernel.org
 help / color / mirror / Atom feed
* [syzbot] [bluetooth?] WARNING: refcount bug in sco_sock_timeout (2)
@ 2023-06-28  7:45 syzbot
  0 siblings, 0 replies; 2+ messages in thread
From: syzbot @ 2023-06-28  7:45 UTC (permalink / raw)
  To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
	netdev, syzkaller-bugs

Hello,

syzbot found the following issue on:

HEAD commit:    42234a752679 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1351201b280000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e95897d034d60fb8
dashboard link: https://syzkaller.appspot.com/bug?extid=c689847e27e0fa3e7a5d
compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f608eaee38d2/disk-42234a75.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/266fc376435a/vmlinux-42234a75.xz
kernel image: https://storage.googleapis.com/syzbot-assets/464f23f26a65/Image-42234a75.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c689847e27e0fa3e7a5d@syzkaller.appspotmail.com

------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 7887 at lib/refcount.c:25 refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 7887 Comm: kworker/0:9 Not tainted 6.4.0-rc7-syzkaller-g42234a752679 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events sco_sock_timeout
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25
lr : refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25
sp : ffff800099ca7af0
x29: ffff800099ca7af0 x28: ffff0001b423c600 x27: ffff0000d2d42218
x26: ffff0000cb783250 x25: 1fffe0001a5a8443 x24: dfff800000000000
x23: dfff800000000000 x22: 0000000000000000 x21: 0000000000000002
x20: ffff0000dd30a080 x19: ffff800090b09000 x18: ffff800099ca6fc0
x17: 0000000000000000 x16: ffff80008a443320 x15: 0000000000000003
x14: 0000000000000000 x13: fffffffffffdc038 x12: 0000000000000001
x11: 0000000000000001 x10: 0000000000000000 x9 : fd2dea7152733000
x8 : fd2dea7152733000 x7 : fffffffffffdc038 x6 : fffffffffffdbfe8
x5 : ffff800099ca73d8 x4 : ffff80008df78f00 x3 : ffff800080597614
x2 : 0000000000000001 x1 : 0000000100000001 x0 : 0000000000000000
Call trace:
 refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 sock_hold include/net/sock.h:777 [inline]
 sco_sock_timeout+0x19c/0x25c net/bluetooth/sco.c:89
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853
irq event stamp: 183728
hardirqs last  enabled at (183727): [<ffff800080351108>] __up_console_sem+0x60/0xb4 kernel/printk/printk.c:347
hardirqs last disabled at (183728): [<ffff80008a43ed34>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:407
softirqs last  enabled at (183698): [<ffff8000803a4f6c>] local_bh_enable+0xc/0x2c include/linux/bottom_half.h:32
softirqs last disabled at (183694): [<ffff8000803a4f40>] local_bh_disable+0xc/0x2c include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 PID: 7887 Comm: kworker/0:9 Tainted: G        W          6.4.0-rc7-syzkaller-g42234a752679 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events sco_sock_timeout
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233
 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 dump_stack+0x1c/0x28 lib/dump_stack.c:113
 assign_lock_key+0x234/0x268 kernel/locking/lockdep.c:982
 register_lock_class+0x144/0x6a4 kernel/locking/lockdep.c:1295
 __lock_acquire+0x184/0x7604 kernel/locking/lockdep.c:4965
 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5705
 lock_sock_nested+0x5c/0x11c net/core/sock.c:3469
 lock_sock include/net/sock.h:1709 [inline]
 sco_sock_timeout+0xbc/0x25c net/bluetooth/sco.c:97
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853
==================================================================
BUG: KASAN: slab-out-of-bounds in sco_sock_timeout+0xe8/0x25c net/bluetooth/sco.c:99
Read of size 8 at addr ffff0000dd30a4a0 by task kworker/0:9/7887

CPU: 0 PID: 7887 Comm: kworker/0:9 Tainted: G        W          6.4.0-rc7-syzkaller-g42234a752679 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events sco_sock_timeout
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233
 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x174/0x514 mm/kasan/report.c:462
 kasan_report+0xd4/0x130 mm/kasan/report.c:572
 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
 sco_sock_timeout+0xe8/0x25c net/bluetooth/sco.c:99
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853

Allocated by task 25544:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x7c mm/kasan/common.c:52
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:510
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:196 [inline]
 __do_kmalloc_node mm/slab_common.c:966 [inline]
 __kmalloc+0xcc/0x1b8 mm/slab_common.c:979
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 ops_init+0x90/0x548 net/core/net_namespace.c:126
 setup_net+0x424/0xaac net/core/net_namespace.c:339
 copy_net_ns+0x3c4/0x644 net/core/net_namespace.c:491
 create_new_namespaces+0x344/0x614 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x108/0x158 kernel/nsproxy.c:228
 ksys_unshare+0x45c/0x874 kernel/fork.c:3441
 __do_sys_unshare kernel/fork.c:3512 [inline]
 __se_sys_unshare kernel/fork.c:3510 [inline]
 __arm64_sys_unshare+0x3c/0x50 kernel/fork.c:3510
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x244 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:191
 el0_svc+0x4c/0x160 arch/arm64/kernel/entry-common.c:647
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591

Last potentially related work creation:
 kasan_save_stack+0x40/0x6c mm/kasan/common.c:45
 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:491
 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:501
 __call_rcu_common kernel/rcu/tree.c:2627 [inline]
 call_rcu+0x104/0xaf4 kernel/rcu/tree.c:2741
 netlink_release+0x12c0/0x1818 net/netlink/af_netlink.c:828
 __sock_release net/socket.c:653 [inline]
 sock_release+0x84/0x140 net/socket.c:681
 netlink_kernel_release+0x50/0x70 net/netlink/af_netlink.c:2098
 nfnetlink_net_exit_batch+0x6c/0xb4 net/netfilter/nfnetlink.c:782
 ops_exit_list net/core/net_namespace.c:175 [inline]
 cleanup_net+0x5dc/0x8d0 net/core/net_namespace.c:614
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853

Second to last potentially related work creation:
 kasan_save_stack+0x40/0x6c mm/kasan/common.c:45
 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:491
 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:501
 __call_rcu_common kernel/rcu/tree.c:2627 [inline]
 call_rcu+0x104/0xaf4 kernel/rcu/tree.c:2741
 netlink_release+0x12c0/0x1818 net/netlink/af_netlink.c:828
 __sock_release net/socket.c:653 [inline]
 sock_close+0xb8/0x1fc net/socket.c:1397
 __fput+0x30c/0x7bc fs/file_table.c:321
 ____fput+0x20/0x30 fs/file_table.c:349
 task_work_run+0x230/0x2e0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x63c/0x1f58 kernel/exit.c:874
 do_group_exit+0x194/0x22c kernel/exit.c:1024
 get_signal+0x14b0/0x159c kernel/signal.c:2876
 do_signal arch/arm64/kernel/signal.c:1249 [inline]
 do_notify_resume+0x3cc/0x3c90 arch/arm64/kernel/signal.c:1302
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:144 [inline]
 el0_svc+0x94/0x160 arch/arm64/kernel/entry-common.c:648
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591

The buggy address belongs to the object at ffff0000dd30a000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 128 bytes to the right of
 allocated 1056-byte region [ffff0000dd30a000, ffff0000dd30a420)

The buggy address belongs to the physical page:
page:0000000078acc899 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11d308
head:0000000078acc899 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000010200 ffff0000c0002900 fffffc00035a2400 dead000000000002
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000dd30a380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000dd30a400: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000dd30a480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff0000dd30a500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000dd30a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
  ESR = 0x0000000086000006
  EC = 0x21: IABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=00000001662e9000
[0000000000000000] pgd=080000011715b003, p4d=080000011715b003, pud=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 7887 Comm: kworker/0:9 Tainted: G    B   W          6.4.0-rc7-syzkaller-g42234a752679 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events sco_sock_timeout
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : sco_sock_timeout+0xf4/0x25c net/bluetooth/sco.c:99
sp : ffff800099ca7b20
x29: ffff800099ca7b20 x28: ffff0001b423c600 x27: ffff0000d2d42218
x26: ffff0000cb783250 x25: 1fffe0001a5a8443 x24: dfff800000000000
x23: dfff800000000000 x22: 0000000000000000 x21: ffff0000cb783208
x20: ffff0000dd30a000 x19: ffff0000dd30a080 x18: 1fffe000368447c6
x17: ffff80008debd000 x16: ffff80008a441e20 x15: 0000000000000002
x14: 0000000000000000 x13: 0000000040000002 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 1fffe000368447c7 x6 : ffff80008028cc04
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff8000801b9aec
x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffff0000dd30a000
Call trace:
 0x0
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853
Code: ???????? ???????? ???????? ???????? (????????) 
---[ end trace 0000000000000000 ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the bug is already fixed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to change bug's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [syzbot] [bluetooth?] WARNING: refcount bug in sco_sock_timeout (2)
@ 2023-12-11 14:15 xingwei lee
  0 siblings, 0 replies; 2+ messages in thread
From: xingwei lee @ 2023-12-11 14:15 UTC (permalink / raw)
  To: syzbot+c689847e27e0fa3e7a5d, syzbot+4c0d0c4cde787116d465,
	syzbot+6b9277cad941daf126a2
  Cc: johan.hedberg, linux-bluetooth, linux-kernel,
	Luiz Augusto von Dentz, marcel, netdev, syzkaller-bugs

Hello.

Notice this bug haven’t reproduce, I try my efforts reproduce this
with repro.c and repro.txt and I confirmed it crashed in the lastest
net tree.
kernel commit: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=e307b5a845c5951dabafc48d00b6424ee64716c4
kernel config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=f8715b6ede5c4b90
However, this repro.c executed in the lastest net tree crashed titled
KASAN: slab-use-after-free Write in sco_sock_timeout
https://syzkaller.appspot.com/bug?extid=4c0d0c4cde787116d465

However, I submit 3 repro.c maybe related to this bug:
https://lore.kernel.org/all/CABOYnLwbz-Es5A+aa28yv-ApQ-X8Dr0E8FzCpLWm-4Vt4DKS1Q@mail.gmail.com/T/

This repro.c seems different from the above three and so I feel it is
necessary to inform.
I don’t analysis deeply and I also don’t know if these two bugs are
the same or related or not.
Hope it helps.

=* repro.c =*
#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/capability.h>
#include <linux/futex.h>
#include <linux/rfkill.h>
#include <pthread.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/epoll.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#ifndef __NR_finit_module
#define __NR_finit_module 313
#endif
#ifndef __NR_landlock_create_ruleset
#define __NR_landlock_create_ruleset 444
#endif

static void sleep_ms(uint64_t ms) { usleep(ms * 1000); }

static uint64_t current_time_ms(void) {
 struct timespec ts;
 if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1);
 return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

static void thread_start(void* (*fn)(void*), void* arg) {
 pthread_t th;
 pthread_attr_t attr;
 pthread_attr_init(&attr);
 pthread_attr_setstacksize(&attr, 128 << 10);
 int i = 0;
 for (; i < 100; i++) {
   if (pthread_create(&th, &attr, fn, arg) == 0) {
     pthread_attr_destroy(&attr);
     return;
   }
   if (errno == EAGAIN) {
     usleep(50);
     continue;
   }
   break;
 }
 exit(1);
}

typedef struct {
 int state;
} event_t;

static void event_init(event_t* ev) { ev->state = 0; }

static void event_reset(event_t* ev) { ev->state = 0; }

static void event_set(event_t* ev) {
 if (ev->state) exit(1);
 __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE);
 syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000);
}

static void event_wait(event_t* ev) {
 while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
   syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0);
}

static int event_isset(event_t* ev) {
 return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE);
}

static int event_timedwait(event_t* ev, uint64_t timeout) {
 uint64_t start = current_time_ms();
 uint64_t now = start;
 for (;;) {
   uint64_t remain = timeout - (now - start);
   struct timespec ts;
   ts.tv_sec = remain / 1000;
   ts.tv_nsec = (remain % 1000) * 1000 * 1000;
   syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts);
   if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) return 1;
   now = current_time_ms();
   if (now - start > timeout) return 0;
 }
}

static bool write_file(const char* file, const char* what, ...) {
 char buf[1024];
 va_list args;
 va_start(args, what);
 vsnprintf(buf, sizeof(buf), what, args);
 va_end(args);
 buf[sizeof(buf) - 1] = 0;
 int len = strlen(buf);
 int fd = open(file, O_WRONLY | O_CLOEXEC);
 if (fd == -1) return false;
 if (write(fd, buf, len) != len) {
   int err = errno;
   close(fd);
   errno = err;
   return false;
 }
 close(fd);
 return true;
}

const int kInitNetNsFd = 201;

#define MAX_FDS 30

static long syz_init_net_socket(volatile long domain, volatile long type,
                               volatile long proto) {
 int netns = open("/proc/self/ns/net", O_RDONLY);
 if (netns == -1) return netns;
 if (setns(kInitNetNsFd, 0)) return -1;
 int sock = syscall(__NR_socket, domain, type, proto);
 int err = errno;
 if (setns(netns, 0)) exit(1);
 close(netns);
 errno = err;
 return sock;
}

#define BTPROTO_HCI 1
#define ACL_LINK 1
#define SCAN_PAGE 2

typedef struct {
 uint8_t b[6];
} __attribute__((packed)) bdaddr_t;

#define HCI_COMMAND_PKT 1
#define HCI_EVENT_PKT 4
#define HCI_VENDOR_PKT 0xff

struct hci_command_hdr {
 uint16_t opcode;
 uint8_t plen;
} __attribute__((packed));

struct hci_event_hdr {
 uint8_t evt;
 uint8_t plen;
} __attribute__((packed));

#define HCI_EV_CONN_COMPLETE 0x03
struct hci_ev_conn_complete {
 uint8_t status;
 uint16_t handle;
 bdaddr_t bdaddr;
 uint8_t link_type;
 uint8_t encr_mode;
} __attribute__((packed));

#define HCI_EV_CONN_REQUEST 0x04
struct hci_ev_conn_request {
 bdaddr_t bdaddr;
 uint8_t dev_class[3];
 uint8_t link_type;
} __attribute__((packed));

#define HCI_EV_REMOTE_FEATURES 0x0b
struct hci_ev_remote_features {
 uint8_t status;
 uint16_t handle;
 uint8_t features[8];
} __attribute__((packed));

#define HCI_EV_CMD_COMPLETE 0x0e
struct hci_ev_cmd_complete {
 uint8_t ncmd;
 uint16_t opcode;
} __attribute__((packed));

#define HCI_OP_WRITE_SCAN_ENABLE 0x0c1a

#define HCI_OP_READ_BUFFER_SIZE 0x1005
struct hci_rp_read_buffer_size {
 uint8_t status;
 uint16_t acl_mtu;
 uint8_t sco_mtu;
 uint16_t acl_max_pkt;
 uint16_t sco_max_pkt;
} __attribute__((packed));

#define HCI_OP_READ_BD_ADDR 0x1009
struct hci_rp_read_bd_addr {
 uint8_t status;
 bdaddr_t bdaddr;
} __attribute__((packed));

#define HCI_EV_LE_META 0x3e
struct hci_ev_le_meta {
 uint8_t subevent;
} __attribute__((packed));

#define HCI_EV_LE_CONN_COMPLETE 0x01
struct hci_ev_le_conn_complete {
 uint8_t status;
 uint16_t handle;
 uint8_t role;
 uint8_t bdaddr_type;
 bdaddr_t bdaddr;
 uint16_t interval;
 uint16_t latency;
 uint16_t supervision_timeout;
 uint8_t clk_accurancy;
} __attribute__((packed));

struct hci_dev_req {
 uint16_t dev_id;
 uint32_t dev_opt;
};

struct vhci_vendor_pkt_request {
 uint8_t type;
 uint8_t opcode;
} __attribute__((packed));

struct vhci_pkt {
 uint8_t type;
 union {
   struct {
     uint8_t opcode;
     uint16_t id;
   } __attribute__((packed)) vendor_pkt;
   struct hci_command_hdr command_hdr;
 };
} __attribute__((packed));

#define HCIDEVUP _IOW('H', 201, int)
#define HCISETSCAN _IOW('H', 221, int)

static int vhci_fd = -1;

static void rfkill_unblock_all() {
 int fd = open("/dev/rfkill", O_WRONLY);
 if (fd < 0) exit(1);
 struct rfkill_event event = {0};
 event.idx = 0;
 event.type = RFKILL_TYPE_ALL;
 event.op = RFKILL_OP_CHANGE_ALL;
 event.soft = 0;
 event.hard = 0;
 if (write(fd, &event, sizeof(event)) < 0) exit(1);
 close(fd);
}

static void hci_send_event_packet(int fd, uint8_t evt, void* data,
                                 size_t data_len) {
 struct iovec iv[3];
 struct hci_event_hdr hdr;
 hdr.evt = evt;
 hdr.plen = data_len;
 uint8_t type = HCI_EVENT_PKT;
 iv[0].iov_base = &type;
 iv[0].iov_len = sizeof(type);
 iv[1].iov_base = &hdr;
 iv[1].iov_len = sizeof(hdr);
 iv[2].iov_base = data;
 iv[2].iov_len = data_len;
 if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1);
}

static void hci_send_event_cmd_complete(int fd, uint16_t opcode, void* data,
                                       size_t data_len) {
 struct iovec iv[4];
 struct hci_event_hdr hdr;
 hdr.evt = HCI_EV_CMD_COMPLETE;
 hdr.plen = sizeof(struct hci_ev_cmd_complete) + data_len;
 struct hci_ev_cmd_complete evt_hdr;
 evt_hdr.ncmd = 1;
 evt_hdr.opcode = opcode;
 uint8_t type = HCI_EVENT_PKT;
 iv[0].iov_base = &type;
 iv[0].iov_len = sizeof(type);
 iv[1].iov_base = &hdr;
 iv[1].iov_len = sizeof(hdr);
 iv[2].iov_base = &evt_hdr;
 iv[2].iov_len = sizeof(evt_hdr);
 iv[3].iov_base = data;
 iv[3].iov_len = data_len;
 if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0) exit(1);
}

static bool process_command_pkt(int fd, char* buf, ssize_t buf_size) {
 struct hci_command_hdr* hdr = (struct hci_command_hdr*)buf;
 if (buf_size < (ssize_t)sizeof(struct hci_command_hdr) ||
     hdr->plen != buf_size - sizeof(struct hci_command_hdr))
   exit(1);
 switch (hdr->opcode) {
   case HCI_OP_WRITE_SCAN_ENABLE: {
     uint8_t status = 0;
     hci_send_event_cmd_complete(fd, hdr->opcode, &status, sizeof(status));
     return true;
   }
   case HCI_OP_READ_BD_ADDR: {
     struct hci_rp_read_bd_addr rp = {0};
     rp.status = 0;
     memset(&rp.bdaddr, 0xaa, 6);
     hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp));
     return false;
   }
   case HCI_OP_READ_BUFFER_SIZE: {
     struct hci_rp_read_buffer_size rp = {0};
     rp.status = 0;
     rp.acl_mtu = 1021;
     rp.sco_mtu = 96;
     rp.acl_max_pkt = 4;
     rp.sco_max_pkt = 6;
     hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp));
     return false;
   }
 }
 char dummy[0xf9] = {0};
 hci_send_event_cmd_complete(fd, hdr->opcode, dummy, sizeof(dummy));
 return false;
}

static void* event_thread(void* arg) {
 while (1) {
   char buf[1024] = {0};
   ssize_t buf_size = read(vhci_fd, buf, sizeof(buf));
   if (buf_size < 0) exit(1);
   if (buf_size > 0 && buf[0] == HCI_COMMAND_PKT) {
     if (process_command_pkt(vhci_fd, buf + 1, buf_size - 1)) break;
   }
 }
 return NULL;
}
#define HCI_HANDLE_1 200
#define HCI_HANDLE_2 201

#define HCI_PRIMARY 0
#define HCI_OP_RESET 0x0c03

static void initialize_vhci() {
 int hci_sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
 if (hci_sock < 0) exit(1);
 vhci_fd = open("/dev/vhci", O_RDWR);
 if (vhci_fd == -1) exit(1);
 const int kVhciFd = 202;
 if (dup2(vhci_fd, kVhciFd) < 0) exit(1);
 close(vhci_fd);
 vhci_fd = kVhciFd;
 struct vhci_vendor_pkt_request vendor_pkt_req = {HCI_VENDOR_PKT, HCI_PRIMARY};
 if (write(vhci_fd, &vendor_pkt_req, sizeof(vendor_pkt_req)) !=
     sizeof(vendor_pkt_req))
   exit(1);
 struct vhci_pkt vhci_pkt;
 if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1);
 if (vhci_pkt.type == HCI_COMMAND_PKT &&
     vhci_pkt.command_hdr.opcode == HCI_OP_RESET) {
   char response[1] = {0};
   hci_send_event_cmd_complete(vhci_fd, HCI_OP_RESET, response,
                               sizeof(response));
   if (read(vhci_fd, &vhci_pkt, sizeof(vhci_pkt)) != sizeof(vhci_pkt)) exit(1);
 }
 if (vhci_pkt.type != HCI_VENDOR_PKT) exit(1);
 int dev_id = vhci_pkt.vendor_pkt.id;
 pthread_t th;
 if (pthread_create(&th, NULL, event_thread, NULL)) exit(1);
 int ret = ioctl(hci_sock, HCIDEVUP, dev_id);
 if (ret) {
   if (errno == ERFKILL) {
     rfkill_unblock_all();
     ret = ioctl(hci_sock, HCIDEVUP, dev_id);
   }
   if (ret && errno != EALREADY) exit(1);
 }
 struct hci_dev_req dr = {0};
 dr.dev_id = dev_id;
 dr.dev_opt = SCAN_PAGE;
 if (ioctl(hci_sock, HCISETSCAN, &dr)) exit(1);
 struct hci_ev_conn_request request;
 memset(&request, 0, sizeof(request));
 memset(&request.bdaddr, 0xaa, 6);
 *(uint8_t*)&request.bdaddr.b[5] = 0x10;
 request.link_type = ACL_LINK;
 hci_send_event_packet(vhci_fd, HCI_EV_CONN_REQUEST, &request,
                       sizeof(request));
 struct hci_ev_conn_complete complete;
 memset(&complete, 0, sizeof(complete));
 complete.status = 0;
 complete.handle = HCI_HANDLE_1;
 memset(&complete.bdaddr, 0xaa, 6);
 *(uint8_t*)&complete.bdaddr.b[5] = 0x10;
 complete.link_type = ACL_LINK;
 complete.encr_mode = 0;
 hci_send_event_packet(vhci_fd, HCI_EV_CONN_COMPLETE, &complete,
                       sizeof(complete));
 struct hci_ev_remote_features features;
 memset(&features, 0, sizeof(features));
 features.status = 0;
 features.handle = HCI_HANDLE_1;
 hci_send_event_packet(vhci_fd, HCI_EV_REMOTE_FEATURES, &features,
                       sizeof(features));
 struct {
   struct hci_ev_le_meta le_meta;
   struct hci_ev_le_conn_complete le_conn;
 } le_conn;
 memset(&le_conn, 0, sizeof(le_conn));
 le_conn.le_meta.subevent = HCI_EV_LE_CONN_COMPLETE;
 memset(&le_conn.le_conn.bdaddr, 0xaa, 6);
 *(uint8_t*)&le_conn.le_conn.bdaddr.b[5] = 0x11;
 le_conn.le_conn.role = 1;
 le_conn.le_conn.handle = HCI_HANDLE_2;
 hci_send_event_packet(vhci_fd, HCI_EV_LE_META, &le_conn, sizeof(le_conn));
 pthread_join(th, NULL);
 close(hci_sock);
}

static void setup_common() {
 if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
 }
}

static void setup_binderfs() {
 if (mkdir("/dev/binderfs", 0777)) {
 }
 if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) {
 }
 if (symlink("/dev/binderfs", "./binderfs")) {
 }
}

static void loop();

static void sandbox_common() {
 prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
 setsid();
 int netns = open("/proc/self/ns/net", O_RDONLY);
 if (netns == -1) exit(1);
 if (dup2(netns, kInitNetNsFd) < 0) exit(1);
 close(netns);
 struct rlimit rlim;
 rlim.rlim_cur = rlim.rlim_max = (200 << 20);
 setrlimit(RLIMIT_AS, &rlim);
 rlim.rlim_cur = rlim.rlim_max = 32 << 20;
 setrlimit(RLIMIT_MEMLOCK, &rlim);
 rlim.rlim_cur = rlim.rlim_max = 136 << 20;
 setrlimit(RLIMIT_FSIZE, &rlim);
 rlim.rlim_cur = rlim.rlim_max = 1 << 20;
 setrlimit(RLIMIT_STACK, &rlim);
 rlim.rlim_cur = rlim.rlim_max = 128 << 20;
 setrlimit(RLIMIT_CORE, &rlim);
 rlim.rlim_cur = rlim.rlim_max = 256;
 setrlimit(RLIMIT_NOFILE, &rlim);
 if (unshare(CLONE_NEWNS)) {
 }
 if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
 }
 if (unshare(CLONE_NEWIPC)) {
 }
 if (unshare(0x02000000)) {
 }
 if (unshare(CLONE_NEWUTS)) {
 }
 if (unshare(CLONE_SYSVSEM)) {
 }
 typedef struct {
   const char* name;
   const char* value;
 } sysctl_t;
 static const sysctl_t sysctls[] = {
     {"/proc/sys/kernel/shmmax", "16777216"},
     {"/proc/sys/kernel/shmall", "536870912"},
     {"/proc/sys/kernel/shmmni", "1024"},
     {"/proc/sys/kernel/msgmax", "8192"},
     {"/proc/sys/kernel/msgmni", "1024"},
     {"/proc/sys/kernel/msgmnb", "1024"},
     {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
 };
 unsigned i;
 for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
   write_file(sysctls[i].name, sysctls[i].value);
}

static int wait_for_loop(int pid) {
 if (pid < 0) exit(1);
 int status = 0;
 while (waitpid(-1, &status, __WALL) != pid) {
 }
 return WEXITSTATUS(status);
}

static void drop_caps(void) {
 struct __user_cap_header_struct cap_hdr = {};
 struct __user_cap_data_struct cap_data[2] = {};
 cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
 cap_hdr.pid = getpid();
 if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1);
 const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
 cap_data[0].effective &= ~drop;
 cap_data[0].permitted &= ~drop;
 cap_data[0].inheritable &= ~drop;
 if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1);
}

static int do_sandbox_none(void) {
 if (unshare(CLONE_NEWPID)) {
 }
 int pid = fork();
 if (pid != 0) return wait_for_loop(pid);
 setup_common();
 initialize_vhci();
 sandbox_common();
 drop_caps();
 if (unshare(CLONE_NEWNET)) {
 }
 write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535");
 setup_binderfs();
 loop();
 exit(1);
}

static void kill_and_wait(int pid, int* status) {
 kill(-pid, SIGKILL);
 kill(pid, SIGKILL);
 for (int i = 0; i < 100; i++) {
   if (waitpid(-1, status, WNOHANG | __WALL) == pid) return;
   usleep(1000);
 }
 DIR* dir = opendir("/sys/fs/fuse/connections");
 if (dir) {
   for (;;) {
     struct dirent* ent = readdir(dir);
     if (!ent) break;
     if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
       continue;
     char abort[300];
     snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
              ent->d_name);
     int fd = open(abort, O_WRONLY);
     if (fd == -1) {
       continue;
     }
     if (write(fd, abort, 1) < 0) {
     }
     close(fd);
   }
   closedir(dir);
 } else {
 }
 while (waitpid(-1, status, __WALL) != pid) {
 }
}

static void setup_test() {
 prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
 setpgrp();
 write_file("/proc/self/oom_score_adj", "1000");
}

static void close_fds() {
 for (int fd = 3; fd < MAX_FDS; fd++) close(fd);
}

struct thread_t {
 int created, call;
 event_t ready, done;
};

static struct thread_t threads[16];
static void execute_call(int call);
static int running;

static void* thr(void* arg) {
 struct thread_t* th = (struct thread_t*)arg;
 for (;;) {
   event_wait(&th->ready);
   event_reset(&th->ready);
   execute_call(th->call);
   __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
   event_set(&th->done);
 }
 return 0;
}

static void execute_one(void) {
 int i, call, thread;
 for (call = 0; call < 15; call++) {
   for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
        thread++) {
     struct thread_t* th = &threads[thread];
     if (!th->created) {
       th->created = 1;
       event_init(&th->ready);
       event_init(&th->done);
       event_set(&th->done);
       thread_start(thr, th);
     }
     if (!event_isset(&th->done)) continue;
     event_reset(&th->done);
     th->call = call;
     __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
     event_set(&th->ready);
     if (call == 1 || call == 4 || call == 5) break;
     event_timedwait(&th->done, 50);
     break;
   }
 }
 for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
   sleep_ms(1);
 close_fds();
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void) {
 int iter = 0;
 for (;; iter++) {
   int pid = fork();
   if (pid < 0) exit(1);
   if (pid == 0) {
     setup_test();
     execute_one();
     exit(0);
   }
   int status = 0;
   uint64_t start = current_time_ms();
   for (;;) {
     if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break;
     sleep_ms(1);
     if (current_time_ms() - start < 5000) continue;
     kill_and_wait(pid, &status);
     break;
   }
 }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_call(int call) {
 intptr_t res = 0;
 switch (call) {
   case 0:
     res = -1;
     res = syz_init_net_socket(/*fam=*/0x1f, /*type=*/5, /*proto=*/2);
     if (res != -1) r[0] = res;
     break;
   case 1:
     *(uint16_t*)0x200002c0 = 0x1f;
     memset((void*)0x200002c2, 0, 6);
     syscall(__NR_connect, /*fd=*/r[0], /*addr=*/0x200002c0ul,
             /*addrlen=*/8ul);
     break;
   case 2:
     *(uint16_t*)0x20000500 = 0x1f;
     memset((void*)0x20000502, 170, 5);
     *(uint8_t*)0x20000507 = 0x11;
     syscall(__NR_connect, /*fd=*/r[0], /*addr=*/0x20000500ul,
             /*addrlen=*/8ul);
     break;
   case 3:
     syscall(__NR_shutdown, /*fd=*/-1, /*how=*/0ul);
     break;
   case 4:
     syscall(__NR_open, /*file=*/0ul, /*flags=*/0x6143c2ul, /*mode=*/0x19ul);
     break;
   case 5:
     syscall(__NR_mkdirat, /*fd=*/-1, /*path=*/0ul, /*mode=*/8ul);
     {
       int i;
       for (i = 0; i < 32; i++) {
         syscall(__NR_mkdirat, /*fd=*/-1, /*path=*/0ul, /*mode=*/8ul);
       }
     }
     break;
   case 6:
     *(uint64_t*)0x20000400 = 0x2081;
     *(uint64_t*)0x20000408 = 1;
     syscall(__NR_landlock_create_ruleset, /*attr=*/0x20000400ul,
             /*size=*/0x10ul, /*flags=*/0ul);
     break;
   case 7:
     syscall(__NR_ioctl, /*fd=*/-1, /*cmd=*/0x708, /*arg=*/0ul);
     break;
   case 8:
     syscall(__NR_getsockopt, /*fd=*/-1, /*level=*/1, /*optname=*/0x11,
             /*optval=*/0ul, /*optlen=*/0ul);
     break;
   case 9:
     syscall(__NR_getsockopt, /*fd=*/-1, /*level=*/0x10f, /*opt=*/0x84,
             /*val=*/0ul, /*len=*/0ul);
     break;
   case 10:
     syscall(__NR_accept, /*fd=*/-1, /*peer=*/0ul, /*peerlen=*/0ul);
     break;
   case 11:
     syscall(__NR_write, /*fd=*/-1, /*buf=*/0x20000a00ul, /*count=*/0ul);
     break;
   case 12:
     syscall(__NR_sendfile, /*fdout=*/-1, /*fdin=*/-1, /*off=*/0ul,
             /*count=*/0xef82ul);
     break;
   case 13:
     *(uint16_t*)0x20000080 = 0x1f;
     memset((void*)0x20000082, 255, 6);
     syscall(__NR_connect, /*fd=*/-1, /*addr=*/0x20000080ul, /*addrlen=*/8ul);
     break;
   case 14:
     syscall(__NR_finit_module, /*fd=*/-1, /*args=*/0ul, /*flags=*/1ul);
     break;
 }
}
int main(void) {
 syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
         /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
 syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul,
         /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
 syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
         /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
 do_sandbox_none();
 return 0;
}

=* repro.txt =*

r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
connect$bt_sco(r0, &(0x7f00000002c0), 0x8) (async)
connect$bt_sco(r0, &(0x7f0000000500)={0x1f,
@fixed={'\xaa\xaa\xaa\xaa\xaa', 0x11}}, 0x8)
shutdown(0xffffffffffffffff, 0x0)
open(0x0, 0x6143c2, 0x19) (async)
mkdirat(0xffffffffffffffff, 0x0, 0x8) (async, rerun: 32)
landlock_create_ruleset(&(0x7f0000000400)={0x2081, 0x1}, 0x10, 0x0)
ioctl$I2C_RDWR(0xffffffffffffffff, 0x708, 0x0)
getsockopt$sock_cred(0xffffffffffffffff, 0x1, 0x11, 0x0, 0x0)
getsockopt$TIPC_SOCK_RECVQ_DEPTH(0xffffffffffffffff, 0x10f, 0x84, 0x0, 0x0)
accept$alg(0xffffffffffffffff, 0x0, 0x0)
write(0xffffffffffffffff, &(0x7f0000000a00), 0x0)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0xef82)
connect$bt_sco(0xffffffffffffffff, &(0x7f0000000080)={0x1f, @none}, 0x8)
finit_module(0xffffffffffffffff, 0x0, 0x1)

and see also https://gist.github.com/xrivendell7/c42e214061ed917254f0725d5564cec6

Best regards
xingwei Lee

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2023-12-11 14:24 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-06-28  7:45 [syzbot] [bluetooth?] WARNING: refcount bug in sco_sock_timeout (2) syzbot
2023-12-11 14:15 xingwei lee

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.