lkml.org 
[lkml]   [2021]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/4] firmware: qemu_fw_cfg: fix sysfs information leak
Date
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@vger.kernel.org # 4.6
Cc: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
drivers/firmware/qemu_fw_cfg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index ccb7ed62452f..f08e056ed0ae 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -598,7 +598,7 @@ static int fw_cfg_register_file(const struct fw_cfg_file *f)
/* 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,
--
2.32.0
\
 
 \ /
  Last update: 2021-12-01 14:32    [W:0.038 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site