[syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    940de590b839 Merge tag 'hardening-v7.3-rc2' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13df50f9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=fefa0af09f7891b1800e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=166a48f9580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=116a48f9580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-940de590.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f3f674f98efb/vmlinux-940de590.xz
kernel image: https://storage.googleapis.com/syzbot-assets/132222426e71/bzImage-940de590.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fefa0af09f7891b1800e@syzkaller.appspotmail.com

wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50
Oops: general protection fault, probably for non-canonical address 0xdffffc000000001c: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000e0-0x00000000000000e7]
CPU: 1 UID: 0 PID: 1158 Comm: kworker/u33:8 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: nvme-reset-wq nvme_loop_reset_ctrl_work
RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:210
Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 e9 0e 36 53 09 66 66 2e 0f 1f 84 00 00 00
RSP: 0018:ffffc90002c2fae0 EFLAGS: 00010082
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8bd0370a RDI: dffffc000000001c
RBP: 00000000000000e0 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffff91452c5f R11: 0000000000000001 R12: ffffffff8bd0370a
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888096a67000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f6824da4 CR3: 000000004c4f1000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __kasan_check_byte+0x13/0x50 mm/kasan/common.c:573
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire kernel/locking/lockdep.c:5882 [inline]
 lock_acquire+0x132/0x380 kernel/locking/lockdep.c:5865
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:181
 blk_mq_quiesce_queue_nowait block/blk-mq.c:265 [inline]
 blk_mq_quiesce_queue+0x21/0x1c0 block/blk-mq.c:301
 nvme_quiesce_admin_queue+0x6e/0x100 drivers/nvme/host/core.c:5412
 nvme_loop_shutdown_ctrl drivers/nvme/target/loop.c:415 [inline]
 nvme_loop_reset_ctrl_work+0xa2/0x5d0 drivers/nvme/target/loop.c:447
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:210
Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 e9 0e 36 53 09 66 66 2e 0f 1f 84 00 00 00
RSP: 0018:ffffc90002c2fae0 EFLAGS: 00010082
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8bd0370a RDI: dffffc000000001c
RBP: 00000000000000e0 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffff91452c5f R11: 0000000000000001 R12: ffffffff8bd0370a
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888096a67000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f6824da4 CR3: 000000004c4f1000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	0f 1f 00             	nopl   (%rax)
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	0f 1f 40 d6          	nopl   -0x2a(%rax)
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 c1 ef 03          	shr    $0x3,%rdi
  27:	48 01 c7             	add    %rax,%rdi
* 2a:	0f b6 07             	movzbl (%rdi),%eax <-- trapping instruction
  2d:	3c 07                	cmp    $0x7,%al
  2f:	0f 96 c0             	setbe  %al
  32:	e9 0e 36 53 09       	jmp    0x9533645
  37:	66                   	data16
  38:	66                   	data16
  39:	2e                   	cs
  3a:	0f                   	.byte 0xf
  3b:	1f                   	(bad)
  3c:	84 00                	test   %al,(%rax)


---
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 report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

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

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

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

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[Edward Adam Davis]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 940de590b839

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index fcb1f8186fdd..ec56085add72 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -561,8 +561,6 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	ctrl->ctrl.opts = opts;
 	INIT_LIST_HEAD(&ctrl->list);
 
-	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
-
 	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops,
 				0 /* no quirks, we're perfect! */);
 	if (ret) {
@@ -593,6 +591,8 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	if (ret)
 		goto out_free_queues;
 
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
+
 	ret = nvme_loop_configure_admin_queue(ctrl);
 	if (ret)
 		goto out_remove_admin_tagset;

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in nvme_reset_ctrl_sync

------------[ cut here ]------------
!list_empty(&work->entry)
WARNING: kernel/workqueue.c:2432 at __queue_work+0xee4/0x1370 kernel/workqueue.c:2432, CPU#0: syz.3.20/6407
Modules linked in:
CPU: 0 UID: 0 PID: 6407 Comm: syz.3.20 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__queue_work+0xee4/0x1370 kernel/workqueue.c:2432
Code: 44 89 f6 e8 9e 35 3b 00 45 84 f6 0f 85 f7 f1 ff ff e9 54 7f 51 ff e8 7b 3b 3b 00 90 0f 0b 90 e9 7c f4 ff ff e8 6d 3b 3b 00 90 <0f> 0b 90 e9 95 f5 ff ff e8 5f 3b 3b 00 4c 89 e2 48 b8 00 00 00 00
RSP: 0018:ffffc90003f57af8 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff888029078800 RCX: 0000000000000001
RDX: ffff8880290a0000 RSI: ffffffff81d000c3 RDI: ffff8880290a0000
RBP: ffff88804c6c8b10 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88804c6c8b18
R13: 1ffff920007eaf69 R14: ffff8880280cd000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888096967000(0063) knlGS:00000000f6804b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00007f04c5506e9c CR3: 000000004e47d000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x180/0x1e0 kernel/workqueue.c:2501
 queue_work include/linux/workqueue.h:700 [inline]
 nvme_reset_ctrl drivers/nvme/host/core.c:226 [inline]
 nvme_reset_ctrl_sync+0x51/0xe0 drivers/nvme/host/core.c:236
 nvme_sysfs_reset+0x35/0x80 drivers/nvme/host/sysfs.c:21
 dev_attr_store+0x58/0x80 drivers/base/core.c:2509
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf702efec
Code: Unable to access opcode bytes at 0xf702efc2.
RSP: 002b:00000000f680450c EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000480
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


Tested on:

commit:         940de590 Merge tag 'hardening-v7.3-rc2' of git://git.k..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16cecb49580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=fefa0af09f7891b1800e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14cca125580000

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[Edward Adam Davis]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 940de590b839

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index fcb1f8186fdd..31f310904412 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -561,8 +561,6 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	ctrl->ctrl.opts = opts;
 	INIT_LIST_HEAD(&ctrl->list);
 
-	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
-
 	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops,
 				0 /* no quirks, we're perfect! */);
 	if (ret) {
@@ -574,8 +572,11 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	if (ret)
 		goto out_put_ctrl;
 
-	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))	{
 		WARN_ON_ONCE(1);
+		ret = -EINVAL;
+		goto out_uninit_ctrl;
+	}
 
 	ret = -ENOMEM;
 
@@ -593,6 +594,8 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	if (ret)
 		goto out_free_queues;
 
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
+
 	ret = nvme_loop_configure_admin_queue(ctrl);
 	if (ret)
 		goto out_remove_admin_tagset;

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in nvme_reset_ctrl_sync

------------[ cut here ]------------
!list_empty(&work->entry)
WARNING: kernel/workqueue.c:2432 at __queue_work+0xee4/0x1370 kernel/workqueue.c:2432, CPU#0: syz-executor138/15710
Modules linked in:
CPU: 0 UID: 0 PID: 15710 Comm: syz-executor138 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__queue_work+0xee4/0x1370 kernel/workqueue.c:2432
Code: 44 89 f6 e8 9e 35 3b 00 45 84 f6 0f 85 f7 f1 ff ff e9 54 7f 51 ff e8 7b 3b 3b 00 90 0f 0b 90 e9 7c f4 ff ff e8 6d 3b 3b 00 90 <0f> 0b 90 e9 95 f5 ff ff e8 5f 3b 3b 00 4c 89 e2 48 b8 00 00 00 00
RSP: 0018:ffffc90006c27af8 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff888028a59800 RCX: 0000000000000001
RDX: ffff888047318000 RSI: ffffffff81d000c3 RDI: ffff888047318000
RBP: ffff88806de38b10 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88806de38b18
R13: 1ffff92000d84f69 R14: ffff8880277bb800 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888096967000(0063) knlGS:00000000f7e0eb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7e0eda4 CR3: 0000000053b7d000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 queue_work_on+0x180/0x1e0 kernel/workqueue.c:2501
 queue_work include/linux/workqueue.h:700 [inline]
 nvme_reset_ctrl drivers/nvme/host/core.c:226 [inline]
 nvme_reset_ctrl_sync+0x51/0xe0 drivers/nvme/host/core.c:236
 nvme_sysfs_reset+0x35/0x80 drivers/nvme/host/sysfs.c:21
 dev_attr_store+0x58/0x80 drivers/base/core.c:2509
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7e37fec
Code: Unable to access opcode bytes at 0xf7e37fc2.
RSP: 002b:00000000f7e0e69c EFLAGS: 00000293 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000480
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000f7e3cd89 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


Tested on:

commit:         940de590 Merge tag 'hardening-v7.3-rc2' of git://git.k..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16baa125580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=fefa0af09f7891b1800e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1172a125580000

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[Edward Adam Davis]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 940de590b839

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 1322c678f4eb..0ad905d62e72 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -600,7 +600,6 @@ bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
 		break;
 	case NVME_CTRL_RESETTING:
 		switch (old_state) {
-		case NVME_CTRL_NEW:
 		case NVME_CTRL_LIVE:
 			changed = true;
 			atomic_long_inc(&ctrl->nr_reset);
diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index fcb1f8186fdd..685f5e8f5302 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -561,8 +561,6 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 	ctrl->ctrl.opts = opts;
 	INIT_LIST_HEAD(&ctrl->list);
 
-	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
-
 	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops,
 				0 /* no quirks, we're perfect! */);
 	if (ret) {
@@ -570,12 +568,16 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
 		goto out;
 	}
 
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
 	ret = nvme_add_ctrl(&ctrl->ctrl);
 	if (ret)
 		goto out_put_ctrl;
 
-	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))	{
 		WARN_ON_ONCE(1);
+		ret = -EINTR;
+		goto out_uninit_ctrl;
+	}
 
 	ret = -ENOMEM;
 

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+fefa0af09f7891b1800e@syzkaller.appspotmail.com
Tested-by: syzbot+fefa0af09f7891b1800e@syzkaller.appspotmail.com

Tested on:

commit:         940de590 Merge tag 'hardening-v7.3-rc2' of git://git.k..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=128808f9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=fefa0af09f7891b1800e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
patch:          https://syzkaller.appspot.com/x/patch.diff?x=13e7d0f9580000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[Edward Adam Davis]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 940de590b839

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index fcb1f8186fdd..39447a72f91c 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -443,6 +443,8 @@ static void nvme_loop_reset_ctrl_work(struct work_struct *work)
 		container_of(work, struct nvme_loop_ctrl, ctrl.reset_work);
 	int ret;
 
+	if (!ctrl->ctrl.admin_q)
+		return;
 	nvme_stop_ctrl(&ctrl->ctrl);
 	nvme_loop_shutdown_ctrl(ctrl);
 

Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in nvme_loop_reset_ctrl_work

------------[ cut here ]------------
1
WARNING: drivers/nvme/target/loop.c:457 at nvme_loop_reset_ctrl_work+0x1d4/0x620 drivers/nvme/target/loop.c:457, CPU#3: kworker/u33:3/62
Modules linked in:
CPU: 3 UID: 0 PID: 62 Comm: kworker/u33:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: nvme-reset-wq nvme_loop_reset_ctrl_work
RIP: 0010:nvme_loop_reset_ctrl_work+0x1d4/0x620 drivers/nvme/target/loop.c:457
Code: 7c 08 84 d2 0f 85 b2 03 00 00 8b 9b dc f8 ff ff bf 01 00 00 00 83 eb 04 89 de e8 c7 fb 59 fb 83 fb 01 76 09 e8 4d 01 5a fb 90 <0f> 0b 90 e8 44 01 5a fb 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc900007dfbd8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000000000000
RDX: ffff888020f72580 RSI: ffffffff86b13ae3 RDI: ffff888020f72580
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000001
R10: 00000000ffffffff R11: 00000000000075fb R12: ffff8880299f83e8
R13: ffff8880299f83ec R14: 0000000000000000 R15: ffff88802886b800
FS:  0000000000000000(0000) GS:ffff888096c67000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7f6e210 CR3: 000000004d58f000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>


Tested on:

commit:         940de590 Merge tag 'hardening-v7.3-rc2' of git://git.k..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=116438f9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=fefa0af09f7891b1800e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
patch:          https://syzkaller.appspot.com/x/patch.diff?x=100438f9580000