[PATCH] add-remove-shell: fix crash when shell is already added

[Timo Teräs]

Avoid dereferencing 'don_add' in strcmp since it is invalid
pointer.

Signed-off-by: Timo Teräs <timo.teras at iki.fi>
---
Please include in -fixes for v1.27.0

 loginutils/add-remove-shell.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/loginutils/add-remove-shell.c b/loginutils/add-remove-shell.c
index 922b3333d..54b62c773 100644
--- a/loginutils/add-remove-shell.c
+++ b/loginutils/add-remove-shell.c
@@ -84,7 +84,7 @@ int add_remove_shell_main(int argc UNUSED_PARAM, char **argv)
 		while ((line = xmalloc_fgetline(orig_fp)) != NULL) {
 			char **cpp = argv;
 			while (*cpp) {
-				if (strcmp(*cpp, line) == 0) {
+				if (*cpp != dont_add && strcmp(*cpp, line) == 0) {
 					/* Old file has this shell name */
 					if (REMOVE_SHELL) {
 						/* we are remove-shell */
-- 
2.13.2