diff mbox series

[net,2/3] amt: fix possible null-ptr-deref in amt_rcv()

Message ID 20220602140108.18329-3-ap420073@gmail.com (mailing list archive)
State Accepted
Commit d16207f92a4a823c48b4ea953ad51f4483456768
Delegated to: Netdev Maintainers
Headers show
Series amt: fix several bugs in amt_rcv() | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1 this patch: 1
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1 this patch: 1
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Taehee Yoo June 2, 2022, 2:01 p.m. UTC
When amt interface receives amt message, it tries to obtain amt private
data from sock.
If there is no amt private data, it frees an skb immediately.
After kfree_skb(), it increases the rx_dropped stats.
But in order to use rx_dropped, amt private data is needed.
So, it makes amt_rcv() to do not increase rx_dropped stats when it can
not obtain amt private data.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 1a1a0e80e005 ("amt: fix possible memory leak in amt_rcv()")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---
 drivers/net/amt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/amt.c b/drivers/net/amt.c
index 900948e135ad..ef483bf51033 100644
--- a/drivers/net/amt.c
+++ b/drivers/net/amt.c
@@ -2698,7 +2698,8 @@  static int amt_rcv(struct sock *sk, struct sk_buff *skb)
 	amt = rcu_dereference_sk_user_data(sk);
 	if (!amt) {
 		err = true;
-		goto drop;
+		kfree_skb(skb);
+		goto out;
 	}
 
 	skb->dev = amt->dev;