[PATCH 4.9 20/28] team: Fix double free in error path

From: Greg Kroah-Hartman
Date: Thu Mar 29 2018 - 14:19:08 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Arkadi Sharshevsky <arkadis@xxxxxxxxxxxx>


[ Upstream commit cbcc607e18422555db569b593608aec26111cb0b ]

The __send_and_alloc_skb() receives a skb ptr as a parameter but in
case it fails the skb is not valid:
- Send failed and released the skb internally.
- Allocation failed.

The current code tries to release the skb in case of failure which
causes redundant freeing.

Fixes: 9b00cf2d1024 ("team: implement multipart netlink messages for options transfers")
Signed-off-by: Arkadi Sharshevsky <arkadis@xxxxxxxxxxxx>
Acked-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/team/team.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -2403,7 +2403,7 @@ send_done:
if (!nlh) {
err = __send_and_alloc_skb(&skb, team, portid, send_func);
if (err)
- goto errout;
+ return err;
goto send_done;
}

@@ -2688,7 +2688,7 @@ send_done:
if (!nlh) {
err = __send_and_alloc_skb(&skb, team, portid, send_func);
if (err)
- goto errout;
+ return err;
goto send_done;
}