ALSA: seq: Fix OOB-reads from strlcpy

BugLink: https://bugs.launchpad.net/bugs/1838116
commit 212ac181c158c09038c474ba68068be49caecebb upstream.

When ioctl calls are made with non-null-terminated userspace strings,
strlcpy causes an OOB-read from within strlen. Fix by changing to use
strscpy instead.

Signed-off-by: Zubin Mithra <zsm@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 6320518cc4dd1082998609f372d609ae7075cdc1..31ab0a2aa5b716ab92e73e441b68eca93f20ba80 100644 (file)
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1253,7 +1253,7 @@ static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
 
        /* fill the info fields */
        if (client_info->name[0])
-               strlcpy(client->name, client_info->name, sizeof(client->name));
+               strscpy(client->name, client_info->name, sizeof(client->name));
 
        client->filter = client_info->filter;
        client->event_lost = client_info->event_lost;
@@ -1531,7 +1531,7 @@ static int snd_seq_ioctl_create_queue(struct snd_seq_client *client, void *arg)
        /* set queue name */
        if (!info->name[0])
                snprintf(info->name, sizeof(info->name), "Queue-%d", q->queue);
-       strlcpy(q->name, info->name, sizeof(q->name));
+       strscpy(q->name, info->name, sizeof(q->name));
        snd_use_lock_free(&q->use_lock);
 
        return 0;
@@ -1593,7 +1593,7 @@ static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
                queuefree(q);
                return -EPERM;
        }
-       strlcpy(q->name, info->name, sizeof(q->name));
+       strscpy(q->name, info->name, sizeof(q->name));
        queuefree(q);
 
        return 0;