[syzbot] [usb?] general protection fault in keyspan_break_ctl

[syzbot] [usb?] general protection fault in keyspan_break_ctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    818bebeb63dd drm/xe: Don't hand out the flat CCS storage a..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16ba2979580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ccca94d2c01b9e78
dashboard link: https://syzkaller.appspot.com/bug?extid=473d7477c523b41d4046
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=161f499e580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-818bebeb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6e4100526b12/vmlinux-818bebeb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/723c4783ee96/bzImage-818bebeb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+473d7477c523b41d4046@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000013: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
CPU: 2 UID: 0 PID: 6029 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:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 54 ca 48 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc900035b7cb0 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87c231ec
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff88802f436000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888034d39020 R14: ffff888034d390c8 R15: 0000000000000000
FS:  0000555589f16500(0000) GS:ffff8880d5da2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bac070000 CR3: 00000000584fe000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 serial_break+0xcb/0x160 drivers/usb/serial/usb-serial.c:538
 send_break drivers/tty/tty_io.c:2458 [inline]
 send_break+0x2ec/0x370 drivers/tty/tty_io.c:2441
 tty_ioctl+0xa2c/0x1640 drivers/tty/tty_io.c:2733
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5bac19e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd93db7608 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5bac425fa0 RCX: 00007f5bac19e0d9
RDX: 0000000000000000 RSI: 0000000000005425 RDI: 0000000000000004
RBP: 00007f5bac235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5bac425fac R14: 00007f5bac425fa0 R15: 00007f5bac425fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 54 ca 48 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc900035b7cb0 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87c231ec
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff88802f436000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888034d39020 R14: ffff888034d390c8 R15: 0000000000000000
FS:  0000555589f16500(0000) GS:ffff8880d5da2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bac070000 CR3: 00000000584fe000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	ff                   	ljmp   (bad)
   1:	e8 54 ca 48 fa       	call   0xfa48ca5a
   6:	83 fb ff             	cmp    $0xffffffff,%ebx
   9:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  10:	fc ff df
  13:	49 8d bc 24 9c 00 00 	lea    0x9c(%r12),%rdi
  1a:	00
  1b:	0f 94 c3             	sete   %bl
  1e:	48 89 fa             	mov    %rdi,%rdx
  21:	0f b6 db             	movzbl %bl,%ebx
  24:	48 c1 ea 03          	shr    $0x3,%rdx
* 28:	0f b6 14 02          	movzbl (%rdx,%rax,1),%edx <-- trapping instruction
  2c:	48 89 f8             	mov    %rdi,%rax
  2f:	83 e0 07             	and    $0x7,%eax
  32:	83 c0 03             	add    $0x3,%eax
  35:	38 d0                	cmp    %dl,%al
  37:	7c 04                	jl     0x3d
  39:	84 d2                	test   %dl,%dl
  3b:	75 1d                	jne    0x5a
  3d:	41                   	rex.B


---
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

Forwarded: [PATCH] usb: serial: keyspan: add debug prints to trace NULL p_priv

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: [PATCH] usb: serial: keyspan: add debug prints to trace NULL p_priv
Author: kartikey406@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master



Add pr_info() calls in keyspan_break_ctl() and keyspan_port_remove()
to trace the lifetime of the per-port private data (p_priv) around
port removal. This is a debugging aid to confirm a suspected race
where a port is unbound (freeing p_priv) while a stale tty fd is
still open, leading to a NULL pointer dereference in
keyspan_break_ctl() when break_ctl is issued afterward.

Not for upstream inclusion - debug only.

Link: https://syzkaller.appspot.com/bug?extid=473d7477c523b41d4046
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
---
 drivers/usb/serial/keyspan.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c
index 4d3746c7a94e..36626c0cc0a9 100644
--- a/drivers/usb/serial/keyspan.c
+++ b/drivers/usb/serial/keyspan.c
@@ -601,9 +601,9 @@ static int keyspan_break_ctl(struct tty_struct *tty, int break_state)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct keyspan_port_private 	*p_priv;
-
 	p_priv = usb_get_serial_port_data(port);
-
+	pr_info("keyspan: break_ctl port=%d p_priv=%px disconnected=%d\n",
+        port->port_number, p_priv, port->serial->disconnected);
 	if (break_state == -1)
 		p_priv->break_on = 1;
 	else
@@ -2975,7 +2975,8 @@ static void keyspan_port_remove(struct usb_serial_port *port)
 	int i;
 
 	p_priv = usb_get_serial_port_data(port);
-
+	pr_info("keyspan: port_remove port=%d freeing p_priv=%px\n",
+        port->port_number, p_priv);
 	usb_kill_urb(p_priv->inack_urb);
 	usb_kill_urb(p_priv->outcont_urb);
 	for (i = 0; i < 2; i++) {
-- 
2.43.0

Re: [syzbot] [usb?] general protection fault in keyspan_break_ctl

[Johan Hovold]

On Thu, Aug 27, 2026 at 11:53:24AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    818bebeb63dd drm/xe: Don't hand out the flat CCS storage a..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16ba2979580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=ccca94d2c01b9e78
> dashboard link: https://syzkaller.appspot.com/bug?extid=473d7477c523b41d4046
> compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=161f499e580000
> 
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-818bebeb.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/6e4100526b12/vmlinux-818bebeb.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/723c4783ee96/bzImage-818bebeb.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+473d7477c523b41d4046@syzkaller.appspotmail.com
> 
> Oops: general protection fault, probably for non-canonical address 0xdffffc0000000013: 0000 [#1] SMP KASAN NOPTI
> KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
> CPU: 2 UID: 0 PID: 6029 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:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
> Code: ff ff ff e8 54 ca 48 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
> RSP: 0018:ffffc900035b7cb0 EFLAGS: 00010203
> RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87c231ec
> RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
> RBP: ffff88802f436000 R08: 0000000000000005 R09: 00000000ffffffff
> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
> R13: ffff888034d39020 R14: ffff888034d390c8 R15: 0000000000000000
> FS:  0000555589f16500(0000) GS:ffff8880d5da2000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f5bac070000 CR3: 00000000584fe000 CR4: 0000000000352ef0
> Call Trace:
>  <TASK>
>  serial_break+0xcb/0x160 drivers/usb/serial/usb-serial.c:538
>  send_break drivers/tty/tty_io.c:2458 [inline]
>  send_break+0x2ec/0x370 drivers/tty/tty_io.c:2441
>  tty_ioctl+0xa2c/0x1640 drivers/tty/tty_io.c:2733
>  vfs_ioctl fs/ioctl.c:51 [inline]

And this is most likely the known issue I've promised to produce a patch
for:

	https://lore.kernel.org/all/ZIGejjOfsWkwjB2s@hovoldconsulting.com/

I'll revisit the fix and post it now...

Johan

Forwarded: [PATCH] tty: fix break race

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: [PATCH] tty: fix break race
Author: adrianox@gmail.com

A timed break (TCSBRK and TCSBRKP) can race against hangup and end up
calling into a tty driver after the underlying device has been removed,
for example when a USB serial device is disconnected while a break is in
progress. This can result in a use-after-free or NULL-pointer dereference
in the driver when the second break_ctl() call is made after the sleep,
as reported for the keyspan USB serial driver.

Make send_break() wait only for the break duration and then check the
hung-up state of the tty before invoking the driver a second time. Since
the tty is marked hung up (f_op == &hung_up_tty_fops) before the device is
torn down, the second break_ctl() is no longer issued after a hangup and
the driver is not called for a device that is gone.

Suggested-by: Johan Hovold <johan@kernel.org>
Reported-by: syzbot+473d7477c523b41d4046@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=473d7477c523b41d4046
Assisted-by: opencode:deepseek-v4-flash
Cc: stable@vger.kernel.org
Signed-off-by: Adriano Cordova <adrianox@gmail.com>
#syz test
---
 drivers/tty/tty_io.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 48569035da56..c9d8a138b84c 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2429,6 +2429,7 @@ static int tiocgetd(struct tty_struct *tty, int __user *p)
 
 /**
  * send_break - performed time break
+ * @file: file object
  * @tty: device to break on
  * @duration: timeout in mS
  *
@@ -2438,7 +2439,7 @@ static int tiocgetd(struct tty_struct *tty, int __user *p)
  * Locking:
  *	@tty->atomic_write_lock serializes
  */
-static int send_break(struct tty_struct *tty, unsigned int duration)
+static int send_break(struct file *file, struct tty_struct *tty, unsigned int duration)
 {
 	int retval;
 
@@ -2455,7 +2456,10 @@ static int send_break(struct tty_struct *tty, unsigned int duration)
 	retval = tty->ops->break_ctl(tty, -1);
 	if (!retval) {
 		msleep_interruptible(duration);
-		retval = tty->ops->break_ctl(tty, 0);
+		if (tty_hung_up_p(file))
+			retval = -EIO;
+		else
+			retval = tty->ops->break_ctl(tty, 0);
 	} else if (retval == -EOPNOTSUPP) {
 		/* some drivers can tell only dynamically */
 		retval = 0;
@@ -2727,10 +2731,10 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		 * This is used by the tcdrain() termios function.
 		 */
 		if (!arg)
-			return send_break(tty, 250);
+			return send_break(file, tty, 250);
 		return 0;
 	case TCSBRKP:	/* support for POSIX tcsendbreak() */
-		return send_break(tty, arg ? arg*100 : 250);
+		return send_break(file, tty, arg ? arg * 100 : 250);
 
 	case TIOCMGET:
 		return tty_tiocmget(tty, p);
-- 
2.51.0

Forwarded:

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org.

***

Subject: 
Author: adrianox@gmail.com

#syz test

Forwarded: [PATCH] tty: protect break handling against disconnect

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org.

***

Subject: [PATCH] tty: protect break handling against disconnect
Author: adrianox@gmail.com

#syz test
Both a timed break (TCSBRK/TCSBRKP) and the unconditional TIOCSBRK/
TIOCCBRK break_ctl() calls can race against hangup and be issued for a
tty whose driver data is gone, causing a use-after-free or NULL-pointer
dereference in the driver.

Check the tty hung-up state before every break_ctl() call in the tty
core, and return -ENODEV in serial_break() once the device is no longer
attached, like serial_write() already does.
---
 drivers/tty/tty_io.c            | 19 +++++++++++++++----
 drivers/usb/serial/usb-serial.c |  3 +++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 48569035da56..272f2839acdb 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2429,6 +2429,7 @@ static int tiocgetd(struct tty_struct *tty, int __user *p)
 
 /**
  * send_break - performed time break
+ * @file: file object
  * @tty: device to break on
  * @duration: timeout in mS
  *
@@ -2438,13 +2439,16 @@ static int tiocgetd(struct tty_struct *tty, int __user *p)
  * Locking:
  *	@tty->atomic_write_lock serializes
  */
-static int send_break(struct tty_struct *tty, unsigned int duration)
+static int send_break(struct file *file, struct tty_struct *tty, unsigned int duration)
 {
 	int retval;
 
 	if (tty->ops->break_ctl == NULL)
 		return 0;
 
+	if (tty_hung_up_p(file))
+		return -EIO;
+
 	if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK)
 		return tty->ops->break_ctl(tty, duration);
 
@@ -2455,7 +2459,10 @@ static int send_break(struct tty_struct *tty, unsigned int duration)
 	retval = tty->ops->break_ctl(tty, -1);
 	if (!retval) {
 		msleep_interruptible(duration);
-		retval = tty->ops->break_ctl(tty, 0);
+		if (tty_hung_up_p(file))
+			retval = -EIO;
+		else
+			retval = tty->ops->break_ctl(tty, 0);
 	} else if (retval == -EOPNOTSUPP) {
 		/* some drivers can tell only dynamically */
 		retval = 0;
@@ -2714,10 +2721,14 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	 * Break handling
 	 */
 	case TIOCSBRK:	/* Turn break on, unconditionally */
+		if (tty_hung_up_p(file))
+			return -EIO;
 		if (tty->ops->break_ctl)
 			return tty->ops->break_ctl(tty, -1);
 		return 0;
 	case TIOCCBRK:	/* Turn break off, unconditionally */
+		if (tty_hung_up_p(file))
+			return -EIO;
 		if (tty->ops->break_ctl)
 			return tty->ops->break_ctl(tty, 0);
 		return 0;
@@ -2727,10 +2738,10 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		 * This is used by the tcdrain() termios function.
 		 */
 		if (!arg)
-			return send_break(tty, 250);
+			return send_break(file, tty, 250);
 		return 0;
 	case TCSBRKP:	/* support for POSIX tcsendbreak() */
-		return send_break(tty, arg ? arg*100 : 250);
+		return send_break(file, tty, arg ? arg * 100 : 250);
 
 	case TIOCMGET:
 		return tty_tiocmget(tty, p);
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 17edc057a311..5f42bfe39212 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -532,6 +532,9 @@ static int serial_break(struct tty_struct *tty, int break_state)
 {
 	struct usb_serial_port *port = tty->driver_data;
 
+	if (port->serial->dev->state == USB_STATE_NOTATTACHED)
+		return -ENODEV;
+
 	dev_dbg(&port->dev, "%s\n", __func__);
 
 	if (port->serial->type->break_ctl)
-- 
2.51.0

Re: [syzbot] [usb?] general protection fault in keyspan_break_ctl

[syzbot]

syzbot has found a reproducer for 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=13537c15580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9
dashboard link: https://syzkaller.appspot.com/bug?extid=473d7477c523b41d4046
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=11f19f79580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15ed50f9580000

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+473d7477c523b41d4046@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000013: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
CPU: 0 UID: 0 PID: 6007 Comm: syz.2.19 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:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 74 88 43 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc900067ffc50 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87c7ae2c
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff888013d9a000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88804a94d020 R14: ffff88804a94d0c8 R15: 0000000000000007
FS:  0000000000000000(0000) GS:ffff888096967000(0063) knlGS:0000000056ebd480
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000ffdb3ff0 CR3: 00000000529f7000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 serial_break+0xcb/0x160 drivers/usb/serial/usb-serial.c:538
 send_break drivers/tty/tty_io.c:2458 [inline]
 send_break+0x2ec/0x370 drivers/tty/tty_io.c:2441
 tty_ioctl+0xa2c/0x1640 drivers/tty/tty_io.c:2733
 tty_compat_ioctl+0x87/0x420 drivers/tty/tty_io.c:2931
 __do_compat_sys_ioctl fs/ioctl.c:695 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:638 [inline]
 __ia32_compat_sys_ioctl+0x2cf/0x360 fs/ioctl.c:638
 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:00000000ff93915c EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000005425
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 74 88 43 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc900067ffc50 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87c7ae2c
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff888013d9a000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88804a94d020 R14: ffff88804a94d0c8 R15: 0000000000000007
FS:  0000000000000000(0000) GS:ffff888096a67000(0063) knlGS:0000000056ebd480
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7349bcc CR3: 00000000529f7000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	ff                   	ljmp   (bad)
   1:	e8 74 88 43 fa       	call   0xfa43887a
   6:	83 fb ff             	cmp    $0xffffffff,%ebx
   9:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  10:	fc ff df
  13:	49 8d bc 24 9c 00 00 	lea    0x9c(%r12),%rdi
  1a:	00
  1b:	0f 94 c3             	sete   %bl
  1e:	48 89 fa             	mov    %rdi,%rdx
  21:	0f b6 db             	movzbl %bl,%ebx
  24:	48 c1 ea 03          	shr    $0x3,%rdx
* 28:	0f b6 14 02          	movzbl (%rdx,%rax,1),%edx <-- trapping instruction
  2c:	48 89 f8             	mov    %rdi,%rax
  2f:	83 e0 07             	and    $0x7,%eax
  32:	83 c0 03             	add    $0x3,%eax
  35:	38 d0                	cmp    %dl,%al
  37:	7c 04                	jl     0x3d
  39:	84 d2                	test   %dl,%dl
  3b:	75 1d                	jne    0x5a
  3d:	41                   	rex.B


---
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