diff mbox series

mctp: Avoid leak of mctp_sk_key

Message ID 20211014074428.3007121-1-matt@codeconstruct.com.au (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series mctp: Avoid leak of mctp_sk_key | expand

Checks

Context Check Description
netdev/cover_letter success Single patches do not need cover letters
netdev/fixes_present success Fixes tag not required for -next series
netdev/patch_count success Link
netdev/tree_selection success Guessed tree name to be net-next
netdev/subject_prefix warning Target tree name not specified in the subject
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes fail Problems with Fixes tag: 1
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/header_inline success No static functions without inline keyword in header files

Commit Message

Matt Johnston Oct. 14, 2021, 7:44 a.m. UTC
mctp_key_alloc() returns a key already referenced.

The mctp_route_input() path receives a packet for a bind socket and
allocates a key. It passes the key to mctp_key_add() which takes a
refcount and adds the key to lists. mctp_route_input() should then
release its own refcount when setting the key pointer to NULL.

In the mctp_alloc_local_tag() path (for mctp_local_output()) we
similarly need to unref the key before returning (mctp_reserve_tag()
takes a refcount and adds the key to lists).

Fixes: 73c618456dc ("mctp: locking, lifetime and validity changes for sk_keys")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
 net/mctp/route.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/net/mctp/route.c b/net/mctp/route.c
index 04781459b2be..82fb5ae524f6 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -372,6 +372,7 @@  static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
 			trace_mctp_key_acquire(key);
 
 			/* we don't need to release key->lock on exit */
+			mctp_key_unref(key);
 			key = NULL;
 
 		} else {
@@ -584,6 +585,9 @@  static int mctp_alloc_local_tag(struct mctp_sock *msk,
 		trace_mctp_key_acquire(key);
 
 		*tagp = key->tag;
+		/* done with the key in this scope */
+		mctp_key_unref(key);
+		key = NULL;
 		rc = 0;
 	}