[PATCH net-next V8 1/2] ptp: ptp_read should not release queue

[PATCH net-next V8 1/2] ptp: ptp_read should not release queue

[Edward Adam Davis]

Firstly, queue is not the memory allocated in ptp_read;
Secondly, other processes may block at ptp_read and wait for conditions to be
met to perform read operations.

Reported-and-tested-by: syzbot+df3f3ef31f60781fa911@syzkaller.appspotmail.com
Fixes: 8f5de6fb2453 ("ptp: support multiple timestamp event readers")
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 drivers/ptp/ptp_chardev.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 473b6d992507..3f7a74788802 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -588,7 +588,5 @@ ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags,
 free_event:
 	kfree(event);
 exit:
-	if (result < 0)
-		ptp_release(pccontext);
 	return result;
 }
-- 
2.25.1

Re: [PATCH net-next V8 1/2] ptp: ptp_read should not release queue

[Richard Cochran]

On Mon, Nov 06, 2023 at 10:31:27PM +0800, Edward Adam Davis wrote:
> Firstly, queue is not the memory allocated in ptp_read;
> Secondly, other processes may block at ptp_read and wait for conditions to be
> met to perform read operations.
> 
> Reported-and-tested-by: syzbot+df3f3ef31f60781fa911@syzkaller.appspotmail.com
> Fixes: 8f5de6fb2453 ("ptp: support multiple timestamp event readers")
> Signed-off-by: Edward Adam Davis <eadavis@qq.com>

(This should go to net and not net-next.)

Acked-by: Richard Cochran <richardcochran@gmail.com>