2023-10-27 03:03:53

by Hangyu Hua

Subject: [PATCH v2] net: 9p: fix possible memory leak in p9_check_errors()

When p9pdu_readf() is called with "s?d" attribute, it allocates a pointer
that will store a string. But when p9pdu_readf() fails while handling "d"
then this pointer will not be freed in p9_check_errors().

Fixes: 51a87c552dfd ("9p: rework client code to use new protocol support functions")
Reviewed-by: Christian Schoenebeck <[email protected]>
Signed-off-by: Hangyu Hua <[email protected]>
---

v2: change the Fixes tag and remove "ename != NULL"

net/9p/client.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/9p/client.c b/net/9p/client.c
index 86bbc7147fc1..b0e7cb7e1a54 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -540,12 +540,14 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
return 0;

if (!p9_is_proto_dotl(c)) {
- char *ename;
+ char *ename = NULL;

err = p9pdu_readf(&req->rc, c->proto_version, "s?d",
&ename, &ecode);
- if (err)
+ if (err) {
+ kfree(ename);
goto out_err;
+ }

if (p9_is_proto_dotu(c) && ecode < 512)
err = -ecode;
--
2.34.1

2023-10-27 03:43:24

by Dominique Martinet

Subject: Re: [PATCH v2] net: 9p: fix possible memory leak in p9_check_errors()

Hangyu Hua wrote on Fri, Oct 27, 2023 at 11:03:02AM +0800:
> When p9pdu_readf() is called with "s?d" attribute, it allocates a pointer
> that will store a string. But when p9pdu_readf() fails while handling "d"
> then this pointer will not be freed in p9_check_errors().
>
> Fixes: 51a87c552dfd ("9p: rework client code to use new protocol support functions")
> Reviewed-by: Christian Schoenebeck <[email protected]>
> Signed-off-by: Hangyu Hua <[email protected]>

Thanks, pushed for next
--
Dominique Martinet | Asmadeus