FAILED: patch "[PATCH] pps: Fix a use-after-free" failed to apply to 6.1-stable tree

PATCH In review [email protected] 3 participants 3 messages Feb 4, 2025 – Feb 7, 2025

Subsystems (5)

Network drivers Stable branch PTP hardware clock support PPS support +1 more subsystems

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author maintainer

2025-02-04 17:53 UTC #0 lore raw

The patch below does not apply to the 6.1-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 <[email protected]>.

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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x c79a39dc8d060b9e64e8b0fa9d245d44befeefbe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025020420-subtly-blaming-0ded@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From c79a39dc8d060b9e64e8b0fa9d245d44befeefbe Mon Sep 17 00:00:00 2001
From: Calvin Owens <[email protected]>
Date: Mon, 11 Nov 2024 20:13:29 -0800
Subject: [PATCH] pps: Fix a use-after-free

On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting:

    pps pps1: removed
    ------------[ cut here ]------------
    kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called.
    WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150
    CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1
    Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT)
    pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
    pc : kobject_put+0x120/0x150
    lr : kobject_put+0x120/0x150
    sp : ffffffc0803d3ae0
    x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001
    x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440
    x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600
    x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000
    x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20
    x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000
    x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
    x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
    x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
    x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
    Call trace:
     kobject_put+0x120/0x150
     cdev_put+0x20/0x3c
     __fput+0x2c4/0x2d8
     ____fput+0x1c/0x38
     task_work_run+0x70/0xfc
     do_exit+0x2a0/0x924
     do_group_exit+0x34/0x90
     get_signal+0x7fc/0x8c0
     do_signal+0x128/0x13b4
     do_notify_resume+0xdc/0x160
     el0_svc+0xd4/0xf8
     el0t_64_sync_handler+0x140/0x14c
     el0t_64_sync+0x190/0x194
    ---[ end trace 0000000000000000 ]---

...followed by more symptoms of corruption, with similar stacks:

refcount_t: underflow; use-after-free.
kernel BUG at lib/list_debug.c:62!
Kernel panic - not syncing: Oops - BUG: Fatal exception

This happens because pps_device_destruct() frees the pps_device with the embedded cdev immediately after calling cdev_del(), but, as the comment above cdev_del() notes, fops for previously opened cdevs are still callable even after cdev_del() returns. I think this bug has always been there: I can't explain why it suddenly started happening every time I reboot this particular board.

In commit d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source."), George Spelvin suggested removing the embedded cdev. That seems like the simplest way to fix this, so I've implemented his suggestion, using __register_chrdev() with pps_idr becoming the source of truth for which minor corresponds to which device.

But now that pps_idr defines userspace visibility instead of cdev_add(), we need to be sure the pps->dev refcount can't reach zero while userspace can still find it again. So, the idr_remove() call moves to pps_unregister_cdev(), and pps_idr now holds a reference to pps->dev.

pps_core: source serial1 got cdev (251:1)
<...>
pps pps1: removed
pps_core: unregistering pps1
pps_core: deallocating pps1

Fixes d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source.")

Cc [email protected]

Signed-off-by Calvin Owens <[email protected]>

Reviewed-by Michal Schmidt <[email protected]>

Link https://lore.kernel.org/r/a17975fd5ae99385791929e563f72564edbcf28f.1731383727.git.calvin@wbinvd.org open here

Signed-off-by Greg Kroah-Hartman <[email protected]>

drivers/pps/clients/pps-gpio.c +2 -2

index 634c3b2f8c26..f77b19884f05 100644
@@ -214,8 +214,8 @@ static int pps_gpio_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	dev_info(data->pps->dev, "Registered IRQ %d as PPS source\n",
-		 data->irq);
+	dev_dbg(&data->pps->dev, "Registered IRQ %d as PPS source\n",
+		data->irq);
 
 	return 0;
 }

drivers/pps/clients/pps-ktimer.c +2 -2

index d33106bd7a29..2f465549b843 100644
@@ -56,7 +56,7 @@ static struct pps_source_info pps_ktimer_info = {
 
 static void __exit pps_ktimer_exit(void)
 {
-	dev_info(pps->dev, "ktimer PPS source unregistered\n");
+	dev_dbg(&pps->dev, "ktimer PPS source unregistered\n");
 
 	del_timer_sync(&ktimer);
 	pps_unregister_source(pps);

@@ -74,7 +74,7 @@ static int __init pps_ktimer_init(void)
 	timer_setup(&ktimer, pps_ktimer_event, 0);
 	mod_timer(&ktimer, jiffies + HZ);
 
-	dev_info(pps->dev, "ktimer PPS source registered\n");
+	dev_dbg(&pps->dev, "ktimer PPS source registered\n");
 
 	return 0;
 }

drivers/pps/clients/pps-ldisc.c +3 -3

index 443d6bae19d1..fa5660f3c4b7 100644
@@ -32,7 +32,7 @@ static void pps_tty_dcd_change(struct tty_struct *tty, bool active)
 	pps_event(pps, &ts, active ? PPS_CAPTUREASSERT :
 			PPS_CAPTURECLEAR, NULL);
 
-	dev_dbg(pps->dev, "PPS %s at %lu\n",
+	dev_dbg(&pps->dev, "PPS %s at %lu\n",
 			active ? "assert" : "clear", jiffies);
 }

@@ -69,7 +69,7 @@ static int pps_tty_open(struct tty_struct *tty)
 		goto err_unregister;
 	}
 
-	dev_info(pps->dev, "source \"%s\" added\n", info.path);
+	dev_dbg(&pps->dev, "source \"%s\" added\n", info.path);
 
 	return 0;

@@ -89,7 +89,7 @@ static void pps_tty_close(struct tty_struct *tty)
 	if (WARN_ON(!pps))
 		return;
 
-	dev_info(pps->dev, "removed\n");
+	dev_info(&pps->dev, "removed\n");
 	pps_unregister_source(pps);
 }

drivers/pps/clients/pps_parport.c +2 -2

index abaffb4e1c1c..24db06750297 100644
@@ -81,7 +81,7 @@ static void parport_irq(void *handle)
 	/* check the signal (no signal means the pulse is lost this time) */
 	if (!signal_is_set(port)) {
 		local_irq_restore(flags);
-		dev_err(dev->pps->dev, "lost the signal\n");
+		dev_err(&dev->pps->dev, "lost the signal\n");
 		goto out_assert;
 	}

@@ -98,7 +98,7 @@ static void parport_irq(void *handle)
 	/* timeout */
 	dev->cw_err++;
 	if (dev->cw_err >= CLEAR_WAIT_MAX_ERRORS) {
-		dev_err(dev->pps->dev, "disabled clear edge capture after %d"
+		dev_err(&dev->pps->dev, "disabled clear edge capture after %d"
 				" timeouts\n", dev->cw_err);
 		dev->cw = 0;
 		dev->cw_err = 0;

drivers/pps/kapi.c +5 -5

index d9d566f70ed1..92d1b62ea239 100644
@@ -41,7 +41,7 @@ static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset)
 static void pps_echo_client_default(struct pps_device *pps, int event,
 		void *data)
 {
-	dev_info(pps->dev, "echo %s %s\n",
+	dev_info(&pps->dev, "echo %s %s\n",
 		event & PPS_CAPTUREASSERT ? "assert" : "",
 		event & PPS_CAPTURECLEAR ? "clear" : "");
 }

@@ -112,7 +112,7 @@ struct pps_device *pps_register_source(struct pps_source_info *info,
 		goto kfree_pps;
 	}
 
-	dev_info(pps->dev, "new PPS source %s\n", info->name);
+	dev_dbg(&pps->dev, "new PPS source %s\n", info->name);
 
 	return pps;

@@ -166,7 +166,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 	/* check event type */
 	BUG_ON((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0);
 
-	dev_dbg(pps->dev, "PPS event at %lld.%09ld\n",
+	dev_dbg(&pps->dev, "PPS event at %lld.%09ld\n",
 			(s64)ts->ts_real.tv_sec, ts->ts_real.tv_nsec);
 
 	timespec_to_pps_ktime(&ts_real, ts->ts_real);

@@ -188,7 +188,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 		/* Save the time stamp */
 		pps->assert_tu = ts_real;
 		pps->assert_sequence++;
-		dev_dbg(pps->dev, "capture assert seq #%u\n",
+		dev_dbg(&pps->dev, "capture assert seq #%u\n",
 			pps->assert_sequence);
 
 		captured = ~0;

@@ -202,7 +202,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 		/* Save the time stamp */
 		pps->clear_tu = ts_real;
 		pps->clear_sequence++;
-		dev_dbg(pps->dev, "capture clear seq #%u\n",
+		dev_dbg(&pps->dev, "capture clear seq #%u\n",
 			pps->clear_sequence);
 
 		captured = ~0;

drivers/pps/kc.c +5 -5

index 50dc59af45be..fbd23295afd7 100644
@@ -43,11 +43,11 @@ int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
 			pps_kc_hardpps_mode = 0;
 			pps_kc_hardpps_dev = NULL;
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_info(pps->dev, "unbound kernel"
+			dev_info(&pps->dev, "unbound kernel"
 					" consumer\n");
 		} else {
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_err(pps->dev, "selected kernel consumer"
+			dev_err(&pps->dev, "selected kernel consumer"
 					" is not bound\n");
 			return -EINVAL;
 		}

@@ -57,11 +57,11 @@ int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
 			pps_kc_hardpps_mode = bind_args->edge;
 			pps_kc_hardpps_dev = pps;
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_info(pps->dev, "bound kernel consumer: "
+			dev_info(&pps->dev, "bound kernel consumer: "
 				"edge=0x%x\n", bind_args->edge);
 		} else {
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_err(pps->dev, "another kernel consumer"
+			dev_err(&pps->dev, "another kernel consumer"
 					" is already bound\n");
 			return -EINVAL;
 		}

@@ -83,7 +83,7 @@ void pps_kc_remove(struct pps_device *pps)
 		pps_kc_hardpps_mode = 0;
 		pps_kc_hardpps_dev = NULL;
 		spin_unlock_irq(&pps_kc_hardpps_lock);
-		dev_info(pps->dev, "unbound kernel consumer"
+		dev_info(&pps->dev, "unbound kernel consumer"
 				" on device removal\n");
 	} else
 		spin_unlock_irq(&pps_kc_hardpps_lock);

drivers/pps/pps.c +66 ~~-61~~

288 lines not on this page · raw message

drivers/ptp/ptp_ocp.c +1 -1

index 5feecaadde8e..120db96d9e95 100644
@@ -4420,7 +4420,7 @@ ptp_ocp_complete(struct ptp_ocp *bp)
 
 	pps = pps_lookup_dev(bp->ptp);
 	if (pps)
-		ptp_ocp_symlink(bp, pps->dev, "pps");
+		ptp_ocp_symlink(bp, &pps->dev, "pps");
 
 	ptp_ocp_debugfs_add_device(bp);

include/linux/pps_kernel.h +1 -2

index 78c8ac4951b5..c7abce28ed29 100644
@@ -56,8 +56,7 @@ struct pps_device {
 
 	unsigned int id;			/* PPS source unique ID */
 	void const *lookup_cookie;		/* For pps_lookup_dev() only */
-	struct cdev cdev;
-	struct device *dev;
+	struct device dev;
 	struct fasync_struct *async_queue;	/* fasync method */
 	spinlock_t lock;
 };

Calvin Owens

2025-02-06 03:00 UTC #1 lore raw

PATCH 1/1 pps: Fix a use-after-free

On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting:

    pps pps1: removed
    ------------[ cut here ]------------
    kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called.
    WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150
    CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1
    Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT)
    pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
    pc : kobject_put+0x120/0x150
    lr : kobject_put+0x120/0x150
    sp : ffffffc0803d3ae0
    x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001
    x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440
    x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600
    x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000
    x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20
    x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000
    x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
    x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
    x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
    x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
    Call trace:
     kobject_put+0x120/0x150
     cdev_put+0x20/0x3c
     __fput+0x2c4/0x2d8
     ____fput+0x1c/0x38
     task_work_run+0x70/0xfc
     do_exit+0x2a0/0x924
     do_group_exit+0x34/0x90
     get_signal+0x7fc/0x8c0
     do_signal+0x128/0x13b4
     do_notify_resume+0xdc/0x160
     el0_svc+0xd4/0xf8
     el0t_64_sync_handler+0x140/0x14c
     el0t_64_sync+0x190/0x194
    ---[ end trace 0000000000000000 ]---

...followed by more symptoms of corruption, with similar stacks:

refcount_t: underflow; use-after-free.
kernel BUG at lib/list_debug.c:62!
Kernel panic - not syncing: Oops - BUG: Fatal exception

pps_core: source serial1 got cdev (251:1)
<...>
pps pps1: removed
pps_core: unregistering pps1
pps_core: deallocating pps1

Fixes d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source.")

Cc [email protected]

Signed-off-by Calvin Owens <[email protected]>

Reviewed-by Michal Schmidt <[email protected]>

Link https://lore.kernel.org/r/a17975fd5ae99385791929e563f72564edbcf28f.1731383727.git.calvin@wbinvd.org open here

Signed-off-by Greg Kroah-Hartman <[email protected]>

(cherry picked from commit c79a39dc8d060b9e64e8b0fa9d245d44befeefbe)

Signed-off-by Calvin Owens <[email protected]>

---
 drivers/pps/clients/pps-gpio.c    |   4 +-
 drivers/pps/clients/pps-ktimer.c  |   4 +-
 drivers/pps/clients/pps-ldisc.c   |   6 +-
 drivers/pps/clients/pps_parport.c |   4 +-
 drivers/pps/kapi.c                |  10 +--
 drivers/pps/kc.c                  |  10 +--
 drivers/pps/pps.c                 | 127 ++++++++++++++++--------------
 drivers/ptp/ptp_ocp.c             |   2 +-
 include/linux/pps_kernel.h        |   3 +-
 9 files changed, 87 insertions(+), 83 deletions(-)

drivers/pps/clients/pps-gpio.c +2 -2

index 2f4b11b4dfcd..bf3b6f1aa984 100644
@@ -214,8 +214,8 @@ static int pps_gpio_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	dev_info(data->pps->dev, "Registered IRQ %d as PPS source\n",
-		 data->irq);
+	dev_dbg(&data->pps->dev, "Registered IRQ %d as PPS source\n",
+		data->irq);
 
 	return 0;
 }

drivers/pps/clients/pps-ktimer.c +2 -2

index d33106bd7a29..2f465549b843 100644
@@ -56,7 +56,7 @@ static struct pps_source_info pps_ktimer_info = {
 
 static void __exit pps_ktimer_exit(void)
 {
-	dev_info(pps->dev, "ktimer PPS source unregistered\n");
+	dev_dbg(&pps->dev, "ktimer PPS source unregistered\n");
 
 	del_timer_sync(&ktimer);
 	pps_unregister_source(pps);

@@ -74,7 +74,7 @@ static int __init pps_ktimer_init(void)
 	timer_setup(&ktimer, pps_ktimer_event, 0);
 	mod_timer(&ktimer, jiffies + HZ);
 
-	dev_info(pps->dev, "ktimer PPS source registered\n");
+	dev_dbg(&pps->dev, "ktimer PPS source registered\n");
 
 	return 0;
 }

drivers/pps/clients/pps-ldisc.c +3 -3

index 443d6bae19d1..fa5660f3c4b7 100644
@@ -32,7 +32,7 @@ static void pps_tty_dcd_change(struct tty_struct *tty, bool active)
 	pps_event(pps, &ts, active ? PPS_CAPTUREASSERT :
 			PPS_CAPTURECLEAR, NULL);
 
-	dev_dbg(pps->dev, "PPS %s at %lu\n",
+	dev_dbg(&pps->dev, "PPS %s at %lu\n",
 			active ? "assert" : "clear", jiffies);
 }

@@ -69,7 +69,7 @@ static int pps_tty_open(struct tty_struct *tty)
 		goto err_unregister;
 	}
 
-	dev_info(pps->dev, "source \"%s\" added\n", info.path);
+	dev_dbg(&pps->dev, "source \"%s\" added\n", info.path);
 
 	return 0;

@@ -89,7 +89,7 @@ static void pps_tty_close(struct tty_struct *tty)
 	if (WARN_ON(!pps))
 		return;
 
-	dev_info(pps->dev, "removed\n");
+	dev_info(&pps->dev, "removed\n");
 	pps_unregister_source(pps);
 }

drivers/pps/clients/pps_parport.c +2 -2

index 53e9c304ae0a..c3f46efd64c3 100644
@@ -81,7 +81,7 @@ static void parport_irq(void *handle)
 	/* check the signal (no signal means the pulse is lost this time) */
 	if (!signal_is_set(port)) {
 		local_irq_restore(flags);
-		dev_err(dev->pps->dev, "lost the signal\n");
+		dev_err(&dev->pps->dev, "lost the signal\n");
 		goto out_assert;
 	}

@@ -98,7 +98,7 @@ static void parport_irq(void *handle)
 	/* timeout */
 	dev->cw_err++;
 	if (dev->cw_err >= CLEAR_WAIT_MAX_ERRORS) {
-		dev_err(dev->pps->dev, "disabled clear edge capture after %d"
+		dev_err(&dev->pps->dev, "disabled clear edge capture after %d"
 				" timeouts\n", dev->cw_err);
 		dev->cw = 0;
 		dev->cw_err = 0;

drivers/pps/kapi.c +5 -5

index d9d566f70ed1..92d1b62ea239 100644
@@ -41,7 +41,7 @@ static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset)
 static void pps_echo_client_default(struct pps_device *pps, int event,
 		void *data)
 {
-	dev_info(pps->dev, "echo %s %s\n",
+	dev_info(&pps->dev, "echo %s %s\n",
 		event & PPS_CAPTUREASSERT ? "assert" : "",
 		event & PPS_CAPTURECLEAR ? "clear" : "");
 }

@@ -112,7 +112,7 @@ struct pps_device *pps_register_source(struct pps_source_info *info,
 		goto kfree_pps;
 	}
 
-	dev_info(pps->dev, "new PPS source %s\n", info->name);
+	dev_dbg(&pps->dev, "new PPS source %s\n", info->name);
 
 	return pps;

@@ -166,7 +166,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 	/* check event type */
 	BUG_ON((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0);
 
-	dev_dbg(pps->dev, "PPS event at %lld.%09ld\n",
+	dev_dbg(&pps->dev, "PPS event at %lld.%09ld\n",
 			(s64)ts->ts_real.tv_sec, ts->ts_real.tv_nsec);
 
 	timespec_to_pps_ktime(&ts_real, ts->ts_real);

@@ -188,7 +188,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 		/* Save the time stamp */
 		pps->assert_tu = ts_real;
 		pps->assert_sequence++;
-		dev_dbg(pps->dev, "capture assert seq #%u\n",
+		dev_dbg(&pps->dev, "capture assert seq #%u\n",
 			pps->assert_sequence);
 
 		captured = ~0;

@@ -202,7 +202,7 @@ void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
 		/* Save the time stamp */
 		pps->clear_tu = ts_real;
 		pps->clear_sequence++;
-		dev_dbg(pps->dev, "capture clear seq #%u\n",
+		dev_dbg(&pps->dev, "capture clear seq #%u\n",
 			pps->clear_sequence);
 
 		captured = ~0;

drivers/pps/kc.c +5 -5

index 50dc59af45be..fbd23295afd7 100644
@@ -43,11 +43,11 @@ int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
 			pps_kc_hardpps_mode = 0;
 			pps_kc_hardpps_dev = NULL;
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_info(pps->dev, "unbound kernel"
+			dev_info(&pps->dev, "unbound kernel"
 					" consumer\n");
 		} else {
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_err(pps->dev, "selected kernel consumer"
+			dev_err(&pps->dev, "selected kernel consumer"
 					" is not bound\n");
 			return -EINVAL;
 		}

@@ -57,11 +57,11 @@ int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
 			pps_kc_hardpps_mode = bind_args->edge;
 			pps_kc_hardpps_dev = pps;
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_info(pps->dev, "bound kernel consumer: "
+			dev_info(&pps->dev, "bound kernel consumer: "
 				"edge=0x%x\n", bind_args->edge);
 		} else {
 			spin_unlock_irq(&pps_kc_hardpps_lock);
-			dev_err(pps->dev, "another kernel consumer"
+			dev_err(&pps->dev, "another kernel consumer"
 					" is already bound\n");
 			return -EINVAL;
 		}

@@ -83,7 +83,7 @@ void pps_kc_remove(struct pps_device *pps)
 		pps_kc_hardpps_mode = 0;
 		pps_kc_hardpps_dev = NULL;
 		spin_unlock_irq(&pps_kc_hardpps_lock);
-		dev_info(pps->dev, "unbound kernel consumer"
+		dev_info(&pps->dev, "unbound kernel consumer"
 				" on device removal\n");
 	} else
 		spin_unlock_irq(&pps_kc_hardpps_lock);

drivers/pps/pps.c +66 ~~-61~~

288 lines not on this page · raw message

drivers/ptp/ptp_ocp.c +1 -1

index 8fee9b330b61..87b960e941ba 100644
@@ -3589,7 +3589,7 @@ ptp_ocp_complete(struct ptp_ocp *bp)
 
 	pps = pps_lookup_dev(bp->ptp);
 	if (pps)
-		ptp_ocp_symlink(bp, pps->dev, "pps");
+		ptp_ocp_symlink(bp, &pps->dev, "pps");
 
 	ptp_ocp_debugfs_add_device(bp);

include/linux/pps_kernel.h +1 -2

index 78c8ac4951b5..c7abce28ed29 100644
@@ -56,8 +56,7 @@ struct pps_device {
 
 	unsigned int id;			/* PPS source unique ID */
 	void const *lookup_cookie;		/* For pps_lookup_dev() only */
-	struct cdev cdev;
-	struct device *dev;
+	struct device dev;
 	struct fasync_struct *async_queue;	/* fasync method */
 	spinlock_t lock;
 };

Signature · 1 line

2.47.2

Sasha Levin

maintainer Reviewed-by Michal Schmidt on v1 1/1

2025-02-07 22:51 UTC #2 lore raw

Re: [PATCH 6.1.y] pps: Fix a use-after-free

[ Sasha's backport helper bot ]

Hi,

Found matching upstream commit: c79a39dc8d060b9e64e8b0fa9d245d44befeefbe

Status in newer kernel trees:
6.13.y | Present (different SHA1: d487d68916ad) 6.12.y | Present (different SHA1: 2423d77f7ee9) 6.6.y | Present (different SHA1: 73f8d5a93c8f) 6.1.y | Not found

Note: The patch differs from the upstream commit:
---
1: c79a39dc8d060 ! 1: 23f60a23048e3 pps: Fix a use-after-free
@@ Commit message

Reviewed-by Michal Schmidt <[email protected]>

Link https://lore.kernel.org/r/a17975fd5ae99385791929e563f72564edbcf28f.1731383727.git.calvin@wbinvd.org open here

Signed-off-by Greg Kroah-Hartman <[email protected]>

+ (cherry picked from commit c79a39dc8d060b9e64e8b0fa9d245d44befeefbe)
+ Signed-off-by: Calvin Owens <[email protected]>

## drivers/pps/clients/pps-gpio.c ##
@@ drivers/pps/clients/pps-gpio.c: static int pps_gpio_probe(struct platform_device *pdev)
@@ drivers/pps/pps.c: EXPORT_SYMBOL(pps_lookup_dev);
{
- int err;
-
- pps_class = class_create("pps");
+ pps_class = class_create(THIS_MODULE, "pps");
if (IS_ERR(pps_class)) {
pr_err("failed to allocate class\n");
@@ drivers/pps/pps.c: static int __init pps_init(void)
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.1.y        |  Success    |  Failed    |

Build Errors:
Build error for stable/linux-6.1.y:

    ssh: connect to host 192.168.1.58 port 22: No route to host