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

Hangyu Hua posted 1 patch 2 years, 1 month ago
net/9p/client.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
[PATCH v2] net: 9p: fix possible memory leak in p9_check_errors()
Posted by Hangyu Hua 2 years, 1 month ago
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 <linux_oss@crudebyte.com>
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
	
	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
Re: [PATCH v2] net: 9p: fix possible memory leak in p9_check_errors()
Posted by asmadeus@codewreck.org 2 years, 1 month ago
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 <linux_oss@crudebyte.com>
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>

Thanks, pushed for next
-- 
Dominique Martinet | Asmadeus