From: Markus Elfring <[email protected]>
Date: Sun, 31 Dec 2023 10:26:25 +0100
The kfree() function was called in one case by
the relay_create_buf() function during error handling
even if the passed data structure member contained a null pointer.
This issue was detected by using the Coccinelle software.
Thus use another label.
Signed-off-by: Markus Elfring <[email protected]>
---
kernel/relay.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/relay.c b/kernel/relay.c
index a8e90e98bf2c..b8c06305213d 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -161,14 +161,15 @@ static struct rchan_buf *relay_create_buf(struct rchan *chan)
buf->start = relay_alloc_buf(buf, &chan->alloc_size);
if (!buf->start)
- goto free_buf;
+ goto free_padding;
buf->chan = chan;
kref_get(&buf->chan->kref);
return buf;
-free_buf:
+free_padding:
kfree(buf->padding);
+free_buf:
kfree(buf);
return NULL;
}
--
2.43.0
On Sun, 31 Dec 2023 10:38:10 +0100 Markus Elfring <[email protected]> wrote:
> From: Markus Elfring <[email protected]>
> Date: Sun, 31 Dec 2023 10:26:25 +0100
>
> The kfree() function was called in one case by
> the relay_create_buf() function during error handling
> even if the passed data structure member contained a null pointer.
> This issue was detected by using the Coccinelle software.
>
> Thus use another label.
>
> ...
>
> --- a/kernel/relay.c
> +++ b/kernel/relay.c
> @@ -161,14 +161,15 @@ static struct rchan_buf *relay_create_buf(struct rchan *chan)
>
> buf->start = relay_alloc_buf(buf, &chan->alloc_size);
> if (!buf->start)
> - goto free_buf;
> + goto free_padding;
>
> buf->chan = chan;
> kref_get(&buf->chan->kref);
> return buf;
>
> -free_buf:
> +free_padding:
> kfree(buf->padding);
> +free_buf:
> kfree(buf);
> return NULL;
> }
kfree(NULL) is an OK thing to do, and is a well-known pattern. Can we
arrange for Coccinelle to understand this?