proc: bootconfig: Add null pointer check

BugLink: https://bugs.launchpad.net/bugs/1969110
commit bed5b60bf67ccd8957b8c0558fead30c4a3f5d3f upstream.

kzalloc is a memory allocation function which can return NULL when some
internal memory errors happen. It is safer to add null pointer check.

Link: https://lkml.kernel.org/r/20220329104004.2376879-1-lv.ruyi@zte.com.cn
Cc: stable@vger.kernel.org
Fixes: c1a3c36017d4 ("proc: bootconfig: Add /proc/bootconfig to show boot config list")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 5b422da35c15a3835be731c98c6dbfb9c5072d41)
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/fs/proc/bootconfig.c b/fs/proc/bootconfig.c
index 6d8d4bf2083773d097ec1fbbf1b1abe34721a731..2e244ada1f970b40dfc11417e5fd43579074d42f 100644 (file)
--- a/fs/proc/bootconfig.c
+++ b/fs/proc/bootconfig.c
@@ -32,6 +32,8 @@ static int __init copy_xbc_key_value_list(char *dst, size_t size)
        int ret = 0;
 
        key = kzalloc(XBC_KEYLEN_MAX, GFP_KERNEL);
+       if (!key)
+               return -ENOMEM;
 
        xbc_for_each_key_value(leaf, val) {
                ret = xbc_node_compose_key(leaf, key, XBC_KEYLEN_MAX);