This is a note to let you know that I've just added the patch titled afs: Increase buffer size in afs_update_volume_status() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: afs-increase-buffer-size-in-afs_update_volume_status.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit bd1ad4f7a865a672be65072e7513419d17a5a8e8 Author: Daniil Dulov <d.dulov@xxxxxxxxxx> Date: Mon Feb 19 14:39:03 2024 +0000 afs: Increase buffer size in afs_update_volume_status() [ Upstream commit 6ea38e2aeb72349cad50e38899b0ba6fbcb2af3d ] The max length of volume->vid value is 20 characters. So increase idbuf[] size up to 24 to avoid overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. [DH: Actually, it's 20 + NUL, so increase it to 24 and use snprintf()] Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation") Signed-off-by: Daniil Dulov <d.dulov@xxxxxxxxxx> Signed-off-by: David Howells <dhowells@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240211150442.3416-1-d.dulov@xxxxxxxxxx/ # v1 Link: https://lore.kernel.org/r/20240212083347.10742-1-d.dulov@xxxxxxxxxx/ # v2 Link: https://lore.kernel.org/r/20240219143906.138346-3-dhowells@xxxxxxxxxx Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/afs/volume.c b/fs/afs/volume.c index f84194b791d3e..fb19c69284ab2 100644 --- a/fs/afs/volume.c +++ b/fs/afs/volume.c @@ -302,7 +302,7 @@ static int afs_update_volume_status(struct afs_volume *volume, struct key *key) { struct afs_server_list *new, *old, *discard; struct afs_vldb_entry *vldb; - char idbuf[16]; + char idbuf[24]; int ret, idsz; _enter(""); @@ -310,7 +310,7 @@ static int afs_update_volume_status(struct afs_volume *volume, struct key *key) /* We look up an ID by passing it as a decimal string in the * operation's name parameter. */ - idsz = sprintf(idbuf, "%llu", volume->vid); + idsz = snprintf(idbuf, sizeof(idbuf), "%llu", volume->vid); vldb = afs_vl_lookup_vldb(volume->cell, key, idbuf, idsz); if (IS_ERR(vldb)) {