This is a note to let you know that I've just added the patch titled
firmware: qemu_fw_cfg: fix sysfs information leak
to the 5.16-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:
firmware-qemu_fw_cfg-fix-sysfs-information-leak.patch
and it can be found in the queue-5.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 1b656e9aad7f4886ed466094d1dc5ee4dd900d20 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Wed, 1 Dec 2021 14:25:27 +0100
Subject: firmware: qemu_fw_cfg: fix sysfs information leak
From: Johan Hovold <johan@xxxxxxxxxx>
commit 1b656e9aad7f4886ed466094d1dc5ee4dd900d20 upstream.
Make sure to always NUL-terminate file names retrieved from the firmware
to avoid accessing data beyond the entry slab buffer and exposing it
through sysfs in case the firmware data is corrupt.
Fixes: 75f3e8e47f38 ("firmware: introduce sysfs driver for QEMU's fw_cfg device")
Cc: stable@xxxxxxxxxxxxxxx # 4.6
Cc: Gabriel Somlo <somlo@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211201132528.30025-4-johan@xxxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/firmware/qemu_fw_cfg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -601,7 +601,7 @@ static int fw_cfg_register_file(const st
/* set file entry information */
entry->size = be32_to_cpu(f->size);
entry->select = be16_to_cpu(f->select);
- memcpy(entry->name, f->name, FW_CFG_MAX_FILE_PATH);
+ strscpy(entry->name, f->name, FW_CFG_MAX_FILE_PATH);
/* register entry under "/sys/firmware/qemu_fw_cfg/by_key/" */
err = kobject_init_and_add(&entry->kobj, &fw_cfg_sysfs_entry_ktype,
Patches currently in stable-queue which might be from johan@xxxxxxxxxx are
queue-5.16/firmware-qemu_fw_cfg-fix-null-pointer-deref-on-duplicate-entries.patch
queue-5.16/firmware-qemu_fw_cfg-fix-sysfs-information-leak.patch
queue-5.16/media-uvcvideo-fix-division-by-zero-at-stream-start.patch
queue-5.16/firmware-qemu_fw_cfg-fix-kobject-leak-in-probe-error-path.patch
