INFO: task hung in gfs2_read_super

From: Dipanjan Das
Date: Wed Jul 27 2022 - 17:08:37 EST

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Hi,

We would like to report the following bug which has been found by our
modified version of syzkaller.

======================================================
description: INFO: task hung in gfs2_read_super
affected file: fs/gfs2/ops_fstype.c
kernel version: 5.10.131
kernel commit: 8f95261a006489c828f1d909355669875649668b
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=e49433cfed49b7d9
crash reproducer: attached
======================================================
Crash log:
======================================================
INFO: task syz-executor.5:11140 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:27224 pid:11140 ppid: 7772 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
io_schedule+0x17/0x70 kernel/sched/core.c:6292
wait_on_page_bit_common+0x333/0xf10 mm/filemap.c:1277
wait_on_page_locked include/linux/pagemap.h:674 [inline]
gfs2_read_super+0xd28/0x1250 fs/gfs2/ops_fstype.c:266
init_names fs/gfs2/ops_fstype.c:371 [inline]
gfs2_fill_super+0x14f2/0x2750 fs/gfs2/ops_fstype.c:1166
get_tree_bdev+0x421/0x740 fs/super.c:1344
gfs2_get_tree+0x4a/0x270 fs/gfs2/ops_fstype.c:1298
vfs_get_tree+0x89/0x2f0 fs/super.c:1549
do_new_mount fs/namespace.c:2899 [inline]
path_mount+0x11c6/0x1b70 fs/namespace.c:3229
do_mount+0xf3/0x110 fs/namespace.c:3242
__do_sys_mount fs/namespace.c:3450 [inline]
__se_sys_mount fs/namespace.c:3427 [inline]
__x64_sys_mount+0x18f/0x230 fs/namespace.c:3427
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fdd892684ed
RSP: 002b:00007fdd87218be8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fdd89386f60 RCX: 00007fdd892684ed
RDX: 0000000020000180 RSI: 0000000020000140 RDI: 0000000020000040
RBP: 00007fdd892d42e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc29abc18f R14: 00007fdd89386f60 R15: 00007fdd87218d80
INFO: task syz-executor.7:11142 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:26472 pid:11142 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba0015fbe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022cdf60 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022cdf60 R15: 00007fba0015fd80
INFO: task syz-executor.7:11156 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:28616 pid:11156 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba0013ebe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022ce040 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022ce040 R15: 00007fba0013ed80
INFO: task syz-executor.7:11157 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:29384 pid:11157 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba0011dbe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022ce120 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022ce120 R15: 00007fba0011dd80
INFO: task syz-executor.7:11158 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:29384 pid:11158 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba000fcbe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022ce200 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022ce200 R15: 00007fba000fcd80
INFO: task syz-executor.7:11159 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:29384 pid:11159 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba000dbbe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022ce2e0 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022ce2e0 R15: 00007fba000dbd80
INFO: task syz-executor.7:11160 blocked for more than 143 seconds.
Tainted: G OE 5.10.131+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.7 state:D stack:29384 pid:11160 ppid: 7769 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3792 [inline]
__schedule+0x8ef/0x20c0 kernel/sched/core.c:4541
schedule+0xcf/0x270 kernel/sched/core.c:4619
rwsem_down_read_slowpath+0x4be/0xfa0 kernel/locking/rwsem.c:1099
__down_read kernel/locking/rwsem.c:1341 [inline]
down_read+0x1e7/0x430 kernel/locking/rwsem.c:1506
iterate_supers+0xdb/0x290 fs/super.c:692
ksys_sync+0x86/0x150 fs/sync.c:114
__do_sys_sync+0xa/0x10 fs/sync.c:125
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fba021af4ed
RSP: 002b:00007fba000babe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fba022ce3c0 RCX: 00007fba021af4ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fba0221b2e1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2a11fc2f R14: 00007fba022ce3c0 R15: 00007fba000bad80

Showing all locks held in the system:
1 lock held by khungtaskd/1658:
#0: ffffffff8b336d60 (rcu_read_lock){....}-{1:2}, at:
debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6389
1 lock held by in:imklog/7747:
#0: ffff88810f7745f0 (&f->f_pos_lock){+.+.}-{3:3}, at:
__fdget_pos+0xe9/0x100 fs/file.c:1003
1 lock held by syz-executor.5/11140:
#0: ffff888111f9c0e0 (&type->s_umount_key#48/1){+.+.}-{3:3}, at:
alloc_super+0x194/0xa40 fs/super.c:229
1 lock held by syz-executor.7/11142:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692
1 lock held by syz-executor.7/11156:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692
1 lock held by syz-executor.7/11157:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692
1 lock held by syz-executor.7/11158:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692
1 lock held by syz-executor.7/11159:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692
1 lock held by syz-executor.7/11160:
#0: ffff888111f9c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at:
iterate_supers+0xdb/0x290 fs/super.c:692

--
Thanks and Regards,

Dipanjan
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

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 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;
}

static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2)
{
if (a0 == 0xc || a0 == 0xb) {
char buf[128];
sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2);
return open(buf, O_RDWR, 0);
} else {
char buf[1024];
char* hash;
strncpy(buf, (char*)a0, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = 0;
while ((hash = strchr(buf, '#'))) {
*hash = '0' + (char)(a1 % 10);
a1 /= 10;
}
return open(buf, a2, 0);
}
}

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 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[2] = {0xffffffffffffffff, 0xffffffffffffffff};

void execute_one(void)
{
intptr_t res = 0;
memcpy((void*)0x200002c0, "/dev/nbd#\000", 10);
res = -1;
res = syz_open_dev(0x200002c0, 0, 0);
if (res != -1)
r[0] = res;
res = syscall(__NR_socketpair, 0x1eul, 5ul, 0, 0x20001c80ul);
if (res != -1)
r[1] = *(uint32_t*)0x20001c80;
syscall(__NR_ioctl, r[0], 0xab00, r[1]);
memcpy((void*)0x20000000, "./file0\000", 8);
syscall(__NR_mkdir, 0x20000000ul, 0ul);
memcpy((void*)0x20000040, "/dev/nbd", 8);
*(uint8_t*)0x20000048 = 0x30;
*(uint8_t*)0x20000049 = 0;
memcpy((void*)0x20000140, "./file0\000", 8);
memcpy((void*)0x20000180, "gfs2\000", 5);
syscall(__NR_mount, 0x20000040ul, 0x20000140ul, 0x20000180ul, 0ul, 0ul);

}
int main(void)
{
syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
loop();
return 0;
}

Attachment: repro.syz
Description: Binary data

Next message: Logan Gunthorpe: "[PATCH 1/5] md/raid5: Refactor raid5_get_active_stripe()"
Previous message: Daniel Lezcano: "[PATCH v3 32/32] thermal/of: Remove old OF code"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]