diff options
author | Russ Weight <russell.h.weight@intel.com> | 2022-08-29 10:45:57 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-01 17:46:54 +0200 |
commit | 8b40c38e37492b5bdf8e95b46b5cca9517a9957a (patch) | |
tree | d930d33cb3332530bbaf6aa1549d4661c55c250e | |
parent | 9b03e79300100bcd36e77c8ce94ee7f47cd2f528 (diff) | |
download | linux-8b40c38e37492b5bdf8e95b46b5cca9517a9957a.tar.bz2 |
firmware_loader: Fix use-after-free during unregister
In the following code within firmware_upload_unregister(), the call to
device_unregister() could result in the dev_release function freeing the
fw_upload_priv structure before it is dereferenced for the call to
module_put(). This bug was found by the kernel test robot using
CONFIG_KASAN while running the firmware selftests.
device_unregister(&fw_sysfs->dev);
module_put(fw_upload_priv->module);
The problem is fixed by copying fw_upload_priv->module to a local variable
for use when calling device_unregister().
Fixes: 97730bbb242c ("firmware_loader: Add firmware-upload support")
Cc: stable <stable@kernel.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/20220829174557.437047-1-russell.h.weight@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/base/firmware_loader/sysfs_upload.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/base/firmware_loader/sysfs_upload.c b/drivers/base/firmware_loader/sysfs_upload.c index 87044d52322a..63e15bddd80c 100644 --- a/drivers/base/firmware_loader/sysfs_upload.c +++ b/drivers/base/firmware_loader/sysfs_upload.c @@ -377,6 +377,7 @@ void firmware_upload_unregister(struct fw_upload *fw_upload) { struct fw_sysfs *fw_sysfs = fw_upload->priv; struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv; + struct module *module = fw_upload_priv->module; mutex_lock(&fw_upload_priv->lock); if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) { @@ -392,6 +393,6 @@ void firmware_upload_unregister(struct fw_upload *fw_upload) unregister: device_unregister(&fw_sysfs->dev); - module_put(fw_upload_priv->module); + module_put(module); } EXPORT_SYMBOL_GPL(firmware_upload_unregister); |