From: Aditya Pakki pakki001@umn.edu
[ Upstream commit 0c85a7e87465f2d4cbc768e245f4f45b2f299b05 ]
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 pakki001@umn.edu Acked-by: Santosh Shilimkar santosh.shilimkar@oracle.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- 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 4b00b1152a5f..e35c9c914df0 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 26e2c2305f7a..f480a447a432 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -655,7 +655,7 @@ 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); }