summaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-22 11:44:32 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-22 11:44:32 -0800
commitb2064617c74f301dab1448f1f9c8dbb3c8021058 (patch)
tree02998695437a023316103256e6c0242e47e4b5eb /kernel
parente30aee9e10bb5168579e047f05c3d13d09e23356 (diff)
parent17627157cda13089d8a6c1c2d35acb07334b899c (diff)
downloadlinux-b2064617c74f301dab1448f1f9c8dbb3c8021058.tar.bz2
Merge tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH: "Here is the "small" driver core patches for 4.11-rc1. Not much here, some firmware documentation and self-test updates, a debugfs code formatting issue, and a new feature for call_usermodehelper to make it more robust on systems that want to lock it down in a more secure way. All of these have been linux-next for a while now with no reported issues" * tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: kernfs: handle null pointers while printing node name and path Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper() Make static usermode helper binaries constant kmod: make usermodehelper path a const string firmware: revamp firmware documentation selftests: firmware: send expected errors to /dev/null selftests: firmware: only modprobe if driver is missing platform: Print the resource range if device failed to claim kref: prefer atomic_inc_not_zero to atomic_add_unless debugfs: improve formatting of debugfs_real_fops()
Diffstat (limited to 'kernel')
-rw-r--r--kernel/kmod.c18
1 files changed, 16 insertions, 2 deletions
diff --git a/kernel/kmod.c b/kernel/kmod.c
index d45c96073afb..0c407f905ca4 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -516,7 +516,7 @@ static void helper_unlock(void)
* Function must be runnable in either a process context or the
* context in which call_usermodehelper_exec is called.
*/
-struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
+struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv,
char **envp, gfp_t gfp_mask,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *info),
@@ -528,7 +528,12 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
goto out;
INIT_WORK(&sub_info->work, call_usermodehelper_exec_work);
+
+#ifdef CONFIG_STATIC_USERMODEHELPER
+ sub_info->path = CONFIG_STATIC_USERMODEHELPER_PATH;
+#else
sub_info->path = path;
+#endif
sub_info->argv = argv;
sub_info->envp = envp;
@@ -566,6 +571,15 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
retval = -EBUSY;
goto out;
}
+
+ /*
+ * If there is no binary for us to call, then just return and get out of
+ * here. This allows us to set STATIC_USERMODEHELPER_PATH to "" and
+ * disable all call_usermodehelper() calls.
+ */
+ if (strlen(sub_info->path) == 0)
+ goto out;
+
/*
* Set the completion pointer only if there is a waiter.
* This makes it possible to use umh_complete to free
@@ -613,7 +627,7 @@ EXPORT_SYMBOL(call_usermodehelper_exec);
* This function is the equivalent to use call_usermodehelper_setup() and
* call_usermodehelper_exec().
*/
-int call_usermodehelper(char *path, char **argv, char **envp, int wait)
+int call_usermodehelper(const char *path, char **argv, char **envp, int wait)
{
struct subprocess_info *info;
gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;