diff mbox series

[v2,net-next,4/9] l2tp: handle hash key collisions in l2tp_v3_session_get

Message ID eae2f69427371bc679626f4d794f2ed59e4bdc86.1723011569.git.jchapman@katalix.com (mailing list archive)
State Accepted
Commit b0a8deda060d51ebe4614ed6e1829d933139ba1a
Delegated to: Netdev Maintainers
Headers show
Series l2tp: misc improvements | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 29 this patch: 29
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 29 this patch: 29
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 29 this patch: 29
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-07--09-00 (tests: 707)

Commit Message

James Chapman Aug. 7, 2024, 6:54 a.m. UTC 
To handle colliding l2tpv3 session IDs, l2tp_v3_session_get searches a
hashed list keyed by ID and sk. Although unlikely, if hash keys
collide, it is possible that hash_for_each_possible loops over a
session which doesn't have the ID that we are searching for. So check
for session ID match when looping over possible hash key matches.

Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
---
 net/l2tp/l2tp_core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 608a7beda9d5..28e6367f2483 100644
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -286,7 +286,8 @@  struct l2tp_session *l2tp_v3_session_get(const struct net *net, struct sock *sk,
 			 */
 			struct l2tp_tunnel *tunnel = READ_ONCE(session->tunnel);
 
-			if (tunnel && tunnel->sock == sk &&
+			if (session->session_id == session_id &&
+			    tunnel && tunnel->sock == sk &&
 			    refcount_inc_not_zero(&session->ref_count)) {
 				rcu_read_unlock_bh();
 				return session;