FAILED: patch "[PATCH] cdc-acm: fix race between initial clearing halt and open" failed to apply to 5.4-stable tree

FAILED: patch "[PATCH] cdc-acm: fix race between initial clearing halt and open" failed to apply to 5.4-stable tree

[gregkh]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 64690a90cd7c6db16d3af8616be1f4bf8d492850
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025081847-user-synthesis-c726@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 64690a90cd7c6db16d3af8616be1f4bf8d492850 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum@suse.com>
Date: Thu, 17 Jul 2025 16:12:50 +0200
Subject: [PATCH] cdc-acm: fix race between initial clearing halt and open

On the devices that need their endpoints to get an
initial clear_halt, this needs to be done before
the devices can be opened. That means it needs to be
before the devices are registered.

Fixes: 15bf722e6f6c0 ("cdc-acm: Add support of ATOL FPrint fiscal printers")
Cc: stable <stable@kernel.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20250717141259.2345605-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index c2ecfa3c8349..5a334e370f4d 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1520,6 +1520,12 @@ static int acm_probe(struct usb_interface *intf,
 			goto err_remove_files;
 	}
 
+	if (quirks & CLEAR_HALT_CONDITIONS) {
+		/* errors intentionally ignored */
+		usb_clear_halt(usb_dev, acm->in);
+		usb_clear_halt(usb_dev, acm->out);
+	}
+
 	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
 			&control_interface->dev);
 	if (IS_ERR(tty_dev)) {
@@ -1527,11 +1533,6 @@ static int acm_probe(struct usb_interface *intf,
 		goto err_release_data_interface;
 	}
 
-	if (quirks & CLEAR_HALT_CONDITIONS) {
-		usb_clear_halt(usb_dev, acm->in);
-		usb_clear_halt(usb_dev, acm->out);
-	}
-
 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
 
 	return 0;

[PATCH 5.4.y 1/2] USB: cdc-acm: do not log successful probe on later errors

[Sasha Levin]

From: Johan Hovold <johan@kernel.org>

[ Upstream commit 79579411826647fd573dbe301c4d933bc90e4be7 ]

Do not log the successful-probe message until the tty device has been
registered.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210322155318.9837-9-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 64690a90cd7c ("cdc-acm: fix race between initial clearing halt and open")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/class/cdc-acm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 59a354822413..51f2caf0fb3e 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1520,8 +1520,6 @@ static int acm_probe(struct usb_interface *intf,
 	acm->nb_index = 0;
 	acm->nb_size = 0;
 
-	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
-
 	acm->line.dwDTERate = cpu_to_le32(9600);
 	acm->line.bDataBits = 8;
 	acm_set_line(acm, &acm->line);
@@ -1541,6 +1539,8 @@ static int acm_probe(struct usb_interface *intf,
 		usb_clear_halt(usb_dev, acm->out);
 	}
 
+	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
+
 	return 0;
 alloc_fail6:
 	if (!acm->combined_interfaces) {
-- 
2.50.1

[PATCH 5.4.y 2/2] cdc-acm: fix race between initial clearing halt and open

[Sasha Levin]

From: Oliver Neukum <oneukum@suse.com>

[ Upstream commit 64690a90cd7c6db16d3af8616be1f4bf8d492850 ]

On the devices that need their endpoints to get an
initial clear_halt, this needs to be done before
the devices can be opened. That means it needs to be
before the devices are registered.

Fixes: 15bf722e6f6c0 ("cdc-acm: Add support of ATOL FPrint fiscal printers")
Cc: stable <stable@kernel.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20250717141259.2345605-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/class/cdc-acm.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 51f2caf0fb3e..4730089a771b 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1527,6 +1527,12 @@ static int acm_probe(struct usb_interface *intf,
 	usb_driver_claim_interface(&acm_driver, data_interface, acm);
 	usb_set_intfdata(data_interface, acm);
 
+	if (quirks & CLEAR_HALT_CONDITIONS) {
+		/* errors intentionally ignored */
+		usb_clear_halt(usb_dev, acm->in);
+		usb_clear_halt(usb_dev, acm->out);
+	}
+
 	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
 			&control_interface->dev);
 	if (IS_ERR(tty_dev)) {
@@ -1534,11 +1540,6 @@ static int acm_probe(struct usb_interface *intf,
 		goto alloc_fail6;
 	}
 
-	if (quirks & CLEAR_HALT_CONDITIONS) {
-		usb_clear_halt(usb_dev, acm->in);
-		usb_clear_halt(usb_dev, acm->out);
-	}
-
 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
 
 	return 0;
-- 
2.50.1