[PATCH v2] kexec/fs2dt: Check for NULL pointer in dt_copy_old_root_param()

[Madhavan Srinivasan]

In dt_copy_old_root_param(), FILE * returned
from fopen is not checked for NULL pointer
before passinig to fclose(). This could trigger
a segfault. Patch to fix the same.

Reviewed-by: Dave Young <dyoung at redhat.com>
Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
---
Changelog v1:
 - Moved the check right after fopen

 kexec/fs2dt.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kexec/fs2dt.c b/kexec/fs2dt.c
index 6ed2399759cf..5ba3ec0fa65c 100644
--- a/kexec/fs2dt.c
+++ b/kexec/fs2dt.c
@@ -524,6 +524,9 @@ static void dt_copy_old_root_param(void)
 	strcpy(filename, pathname);
 	strcat(filename, "bootargs");
 	fp = fopen(filename, "r");
+	if (!fp)
+		return;
+
 	if (fp) {
 		if (getline(&last_cmdline, &len, fp) == -1)
 			die("unable to read %s\n", filename);
-- 
2.7.4