From 0c85a7e87465f2d4cbc768e245f4f45b2f299b05 Mon Sep 17 00:00:00 2001 From: Aditya Pakki Date: Tue, 6 Apr 2021 19:09:12 -0500 Subject: net/rds: Avoid potential use after free in rds_send_remove_from_sock In case of rs failure in rds_send_remove_from_sock(), the 'rm' resource is freed and later under spinlock, causing potential use-after-free. Set the free pointer to NULL to avoid undefined behavior. Signed-off-by: Aditya Pakki Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller --- net/rds/message.c | 1 + net/rds/send.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/net/rds/message.c b/net/rds/message.c index 799034e0f513..4fc66ff0f1ec 100644 --- a/net/rds/message.c +++ b/net/rds/message.c @@ -180,6 +180,7 @@ void rds_message_put(struct rds_message *rm) rds_message_purge(rm); kfree(rm); + rm = NULL; } } EXPORT_SYMBOL_GPL(rds_message_put); diff --git a/net/rds/send.c b/net/rds/send.c index 985d0b7713ac..fe5264b9d4b3 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -665,7 +665,7 @@ static void rds_send_remove_from_sock(struct list_head *messages, int status) unlock_and_drop: spin_unlock_irqrestore(&rm->m_rs_lock, flags); rds_message_put(rm); - if (was_on_sock) + if (was_on_sock && rm) rds_message_put(rm); } -- cgit v1.2.3-59-g8ed1b