* [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds
2025-07-24 18:12 [PATCH 5.10.y] comedi: Fail COMEDI_INSNLIST ioctl if n_insns is too large Ian Abbott
@ 2025-07-24 18:12 ` Ian Abbott
2025-07-25 23:24 ` Sasha Levin
0 siblings, 1 reply; 4+ messages in thread
From: Ian Abbott @ 2025-07-24 18:12 UTC (permalink / raw)
To: stable; +Cc: Ian Abbott, syzbot+32de323b0addb9e114ff, Greg Kroah-Hartman
[ Upstream commit b14b076ce593f72585412fc7fd3747e03a5e3632 ]
When checking for a supported IRQ number, the following test is used:
if ((1 << it->options[1]) & board->irq_bits) {
However, `it->options[i]` is an unchecked `int` value from userspace, so
the shift amount could be negative or out of bounds. Fix the test by
requiring `it->options[1]` to be within bounds before proceeding with
the original test. Valid `it->options[1]` values that select the IRQ
will be in the range [1,15]. The value 0 explicitly disables the use of
interrupts.
Reported-by: syzbot+32de323b0addb9e114ff@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=32de323b0addb9e114ff
Fixes: fcdb427bc7cf ("Staging: comedi: add pcl821 driver")
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20250707133429.73202-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/comedi/drivers/pcl812.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c
index b87ab3840eee..fc06f284ba74 100644
--- a/drivers/staging/comedi/drivers/pcl812.c
+++ b/drivers/staging/comedi/drivers/pcl812.c
@@ -1151,7 +1151,8 @@ static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
if (!dev->pacer)
return -ENOMEM;
- if ((1 << it->options[1]) & board->irq_bits) {
+ if (it->options[1] > 0 && it->options[1] < 16 &&
+ (1 << it->options[1]) & board->irq_bits) {
ret = request_irq(it->options[1], pcl812_interrupt, 0,
dev->board_name, dev);
if (ret == 0)
--
2.47.2
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds
@ 2025-07-24 18:16 Ian Abbott
2025-07-26 1:01 ` Sasha Levin
0 siblings, 1 reply; 4+ messages in thread
From: Ian Abbott @ 2025-07-24 18:16 UTC (permalink / raw)
To: stable; +Cc: Ian Abbott, syzbot+32de323b0addb9e114ff, Greg Kroah-Hartman
[ Upstream commit b14b076ce593f72585412fc7fd3747e03a5e3632 ]
When checking for a supported IRQ number, the following test is used:
if ((1 << it->options[1]) & board->irq_bits) {
However, `it->options[i]` is an unchecked `int` value from userspace, so
the shift amount could be negative or out of bounds. Fix the test by
requiring `it->options[1]` to be within bounds before proceeding with
the original test. Valid `it->options[1]` values that select the IRQ
will be in the range [1,15]. The value 0 explicitly disables the use of
interrupts.
Reported-by: syzbot+32de323b0addb9e114ff@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=32de323b0addb9e114ff
Fixes: fcdb427bc7cf ("Staging: comedi: add pcl821 driver")
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20250707133429.73202-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/comedi/drivers/pcl812.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c
index b87ab3840eee..fc06f284ba74 100644
--- a/drivers/staging/comedi/drivers/pcl812.c
+++ b/drivers/staging/comedi/drivers/pcl812.c
@@ -1151,7 +1151,8 @@ static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
if (!dev->pacer)
return -ENOMEM;
- if ((1 << it->options[1]) & board->irq_bits) {
+ if (it->options[1] > 0 && it->options[1] < 16 &&
+ (1 << it->options[1]) & board->irq_bits) {
ret = request_irq(it->options[1], pcl812_interrupt, 0,
dev->board_name, dev);
if (ret == 0)
--
2.47.2
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds
2025-07-24 18:12 ` [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds Ian Abbott
@ 2025-07-25 23:24 ` Sasha Levin
0 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2025-07-25 23:24 UTC (permalink / raw)
To: stable; +Cc: Sasha Levin
[ Sasha's backport helper bot ]
Hi,
✅ All tests passed successfully. No issues detected.
No action required from the submitter.
The upstream commit SHA1 provided is correct: b14b076ce593f72585412fc7fd3747e03a5e3632
Status in newer kernel trees:
6.15.y | Not found
6.12.y | Not found
6.6.y | Not found
6.1.y | Not found
5.15.y | Not found
Note: The patch differs from the upstream commit:
---
1: b14b076ce593 ! 1: b9004585cda3 comedi: pcl812: Fix bit shift out of bounds
@@ Metadata
## Commit message ##
comedi: pcl812: Fix bit shift out of bounds
+ [ Upstream commit b14b076ce593f72585412fc7fd3747e03a5e3632 ]
+
When checking for a supported IRQ number, the following test is used:
if ((1 << it->options[1]) & board->irq_bits) {
@@ Commit message
Link: https://lore.kernel.org/r/20250707133429.73202-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- ## drivers/comedi/drivers/pcl812.c ##
-@@ drivers/comedi/drivers/pcl812.c: static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
- if (IS_ERR(dev->pacer))
- return PTR_ERR(dev->pacer);
+ ## drivers/staging/comedi/drivers/pcl812.c ##
+@@ drivers/staging/comedi/drivers/pcl812.c: static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
+ if (!dev->pacer)
+ return -ENOMEM;
- if ((1 << it->options[1]) & board->irq_bits) {
+ if (it->options[1] > 0 && it->options[1] < 16 &&
---
Results of testing on various branches:
| Branch | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| origin/linux-5.10.y | Success | Success |
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds
2025-07-24 18:16 [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds Ian Abbott
@ 2025-07-26 1:01 ` Sasha Levin
0 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2025-07-26 1:01 UTC (permalink / raw)
To: stable; +Cc: Sasha Levin
[ Sasha's backport helper bot ]
Hi,
✅ All tests passed successfully. No issues detected.
No action required from the submitter.
The upstream commit SHA1 provided is correct: b14b076ce593f72585412fc7fd3747e03a5e3632
Status in newer kernel trees:
6.15.y | Not found
6.12.y | Not found
6.6.y | Not found
6.1.y | Not found
5.15.y | Not found
Note: The patch differs from the upstream commit:
---
1: b14b076ce593 ! 1: 08dbf07f845c comedi: pcl812: Fix bit shift out of bounds
@@ Metadata
## Commit message ##
comedi: pcl812: Fix bit shift out of bounds
+ [ Upstream commit b14b076ce593f72585412fc7fd3747e03a5e3632 ]
+
When checking for a supported IRQ number, the following test is used:
if ((1 << it->options[1]) & board->irq_bits) {
@@ Commit message
Link: https://lore.kernel.org/r/20250707133429.73202-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- ## drivers/comedi/drivers/pcl812.c ##
-@@ drivers/comedi/drivers/pcl812.c: static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
- if (IS_ERR(dev->pacer))
- return PTR_ERR(dev->pacer);
+ ## drivers/staging/comedi/drivers/pcl812.c ##
+@@ drivers/staging/comedi/drivers/pcl812.c: static int pcl812_attach(struct comedi_device *dev, struct comedi_devconfig *it)
+ if (!dev->pacer)
+ return -ENOMEM;
- if ((1 << it->options[1]) & board->irq_bits) {
+ if (it->options[1] > 0 && it->options[1] < 16 &&
---
Results of testing on various branches:
| Branch | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| origin/linux-5.10.y | Success | Success |
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2025-07-26 1:01 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-07-24 18:16 [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds Ian Abbott
2025-07-26 1:01 ` Sasha Levin
-- strict thread matches above, loose matches on Subject: below --
2025-07-24 18:12 [PATCH 5.10.y] comedi: Fail COMEDI_INSNLIST ioctl if n_insns is too large Ian Abbott
2025-07-24 18:12 ` [PATCH 5.10.y] comedi: pcl812: Fix bit shift out of bounds Ian Abbott
2025-07-25 23:24 ` Sasha Levin
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox