From: Kees Cook <keescook@chromium.org>
Date: Fri, 8 May 2020 16:16:02 +0000 (-0700)
Subject: pstore/platform: Switch pstore_info::name to const
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=563ca40ddf400dbf8c6254077f9b6887101d0f08;p=linux.git

pstore/platform: Switch pstore_info::name to const

In order to more cleanly pass around backend names, make the "name" member
const. This means the module param needs to be dynamic (technically, it
was before, so this actually cleans up a minor memory leak if a backend
was specified and then gets unloaded.)

Link: https://lore.kernel.org/lkml/20200510202436.63222-3-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
---

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 8beaeff723863..715396bef0eab 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -624,7 +624,7 @@ int pstore_register(struct pstore_info *psi)
 	 * Update the module parameter backend, so it is visible
 	 * through /sys/module/pstore/parameters/backend
 	 */
-	backend = psi->name;
+	backend = kstrdup(psi->name, GFP_KERNEL);
 
 	pr_info("Registered %s as persistent store backend\n", psi->name);
 
@@ -667,6 +667,7 @@ void pstore_unregister(struct pstore_info *psi)
 	free_buf_for_compression();
 
 	psinfo = NULL;
+	kfree(backend);
 	backend = NULL;
 	mutex_unlock(&psinfo_lock);
 }
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index e779441e6d26c..f6f22b13e04fc 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -170,7 +170,7 @@ struct pstore_record {
  */
 struct pstore_info {
 	struct module	*owner;
-	char		*name;
+	const char	*name;
 
 	struct semaphore buf_lock;
 	char		*buf;