This is a note to let you know that I've just added the patch titled
ptp: Properly handle compat ioctls
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ptp-properly-handle-compat-ioctls.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7d612e2d279e7223b19b6a2d11d480396dcb37e9
Author: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
Date: Sat Jan 25 10:28:38 2025 +0100
ptp: Properly handle compat ioctls
[ Upstream commit 19ae40f572a9ce1ade9954990af709a03fd37010 ]
Pointer arguments passed to ioctls need to pass through compat_ptr() to
work correctly on s390; as explained in Documentation/driver-api/ioctl.rst.
Detect compat mode at runtime and call compat_ptr() for those commands
which do take pointer arguments.
Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
Link: https://lore.kernel.org/lkml/1ba5d3a4-7931-455b-a3ce-85a968a7cb10@xxxxxxxxxxxxxxxx/
Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.")
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
Reviewed-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>
Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>
Acked-by: Richard Cochran <richardcochran@xxxxxxxxx>
Link: https://patch.msgid.link/20250125-posix-clock-compat_ioctl-v2-1-11c865c500eb@xxxxxxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index c48b9379ca094..8912e3efa00e2 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -4,6 +4,7 @@
*
* Copyright (C) 2010 OMICRON electronics GmbH
*/
+#include <linux/compat.h>
#include <linux/module.h>
#include <linux/posix-clock.h>
#include <linux/poll.h>
@@ -159,6 +160,9 @@ long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
struct timespec64 ts;
int enable, err = 0;
+ if (in_compat_syscall() && cmd != PTP_ENABLE_PPS && cmd != PTP_ENABLE_PPS2)
+ arg = (unsigned long)compat_ptr(arg);
+
tsevq = pccontext->private_clkdata;
switch (cmd) {
