From: Thomas Weißschuh linux@weissschuh.net
commit fd53aa40e65f518453115b6f56183b0c201db26b upstream.
The ioctl and sysfs handlers unconditionally call the ->enable callback. Not all drivers implement that callback, leading to NULL dereferences. Example of affected drivers: ptp_s390.c, ptp_vclock.c and ptp_mock.c.
Instead use a dummy callback if no better was specified by the driver.
Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh linux@weissschuh.net Acked-by: Richard Cochran richardcochran@gmail.com Reviewed-by: Michal Swiatkowski michal.swiatkowski@linux.intel.com Link: https://patch.msgid.link/20250123-ptp-enable-v1-1-b015834d3a47@weissschuh.ne... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [Conflict due to 42704b26b0f1 ("ptp: Add cycles support for virtual clocks") not in the tree] Signed-off-by: Abdelkareem Abdelsaamad kareemem@amazon.com --- drivers/ptp/ptp_clock.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 4d775cd8ee3c..c895e26b1f17 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -188,6 +188,11 @@ static void ptp_clock_release(struct device *dev) kfree(ptp); }
+static int ptp_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *request, int on) +{ + return -EOPNOTSUPP; +} + static void ptp_aux_kworker(struct kthread_work *work) { struct ptp_clock *ptp = container_of(work, struct ptp_clock, @@ -233,6 +238,9 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, mutex_init(&ptp->pincfg_mux); init_waitqueue_head(&ptp->tsev_wq);
+ if (!ptp->info->enable) + ptp->info->enable = ptp_enable; + if (ptp->info->do_aux_work) { kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker); ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
[ Sasha's backport helper bot ]
Hi,
Summary of potential issues: ❌ Build failures detected
The upstream commit SHA1 provided is correct: fd53aa40e65f518453115b6f56183b0c201db26b
WARNING: Author mismatch between patch and upstream commit: Backport author: Abdelkareem Abdelsaamadkareemem@amazon.com Commit author: Thomas Weißschuhlinux@weissschuh.net
Status in newer kernel trees: 6.13.y | Present (different SHA1: 755caf4ee1c6) 6.12.y | Present (different SHA1: 8441aea46445) 6.6.y | Present (different SHA1: 81846070cba1) 6.1.y | Present (different SHA1: 5d1041c76de6) 5.15.y | Present (different SHA1: fd80c97b94f0)
Note: The patch differs from the upstream commit: --- Failed to apply patch cleanly. ---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-5.10.y | Failed | N/A | | stable/linux-5.15.y | Failed | N/A |
Build Errors: Patch failed to apply on stable/linux-5.10.y. Reject:
diff a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c (rejected hunks) @@ -188,6 +188,11 @@ static void ptp_clock_release(struct device *dev) kfree(ptp); }
+static int ptp_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *request, int on) +{ + return -EOPNOTSUPP; +} + static void ptp_aux_kworker(struct kthread_work *work) { struct ptp_clock *ptp = container_of(work, struct ptp_clock, @@ -233,6 +238,9 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, mutex_init(&ptp->pincfg_mux); init_waitqueue_head(&ptp->tsev_wq);
+ if (!ptp->info->enable) + ptp->info->enable = ptp_enable; + if (ptp->info->do_aux_work) { kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker); ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
Patch failed to apply on stable/linux-5.15.y. Reject:
diff a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c (rejected hunks) @@ -188,6 +188,11 @@ static void ptp_clock_release(struct device *dev) kfree(ptp); }
+static int ptp_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *request, int on) +{ + return -EOPNOTSUPP; +} + static void ptp_aux_kworker(struct kthread_work *work) { struct ptp_clock *ptp = container_of(work, struct ptp_clock, @@ -233,6 +238,9 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, mutex_init(&ptp->pincfg_mux); init_waitqueue_head(&ptp->tsev_wq);
+ if (!ptp->info->enable) + ptp->info->enable = ptp_enable; + if (ptp->info->do_aux_work) { kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker); ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
linux-stable-mirror@lists.linaro.org
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Abdelkareem Abdelsaamad -
Sasha Levin