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 <pakki001@umn.edu>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Aditya Pakki 2021-04-06 19:09:12 -05:00 committed by David S. Miller
parent 5219d6012d
commit 0c85a7e874
2 changed files with 2 additions and 1 deletions

View File

@ -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);

View File

@ -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);
}