[PATCH 1/2] expand_user_path: do not look at NULL path
- From
Jeff King <peff@peff.net>
- Date
- Jan 28, 2014, 01:36 UTC
- Message-ID
- <20140128013612.GA29548@sigill.intra.peff.net>
We explicitly check for and handle the case that the incoming "path" variable is NULL, but before doing so we call strchrnul on it, leading to a potential segfault.
We can fix this simply by moving the strchrnul call down; as a bonus, we can tighten the scope on the associated variable.
Signed-off-by: Jeff King <peff@peff.net> --- Most of the callers already check for NULL, so the only way to trigger this is via an empty "include.path". That is addressed separately in the next patch, so technically this is not needed if we apply that one. But in that case, the "path == NULL" check here is useless, so I think this makes things safer overall.
path.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/path.c b/path.c index 24594c4..f9c5062 100644 --- a/path.c +++ b/path.c @@ -265,12 +265,12 @@ static struct passwd *getpw_str(const char *username, size_t len) char *expand_user_path(const char *path) { struct strbuf user_path = STRBUF_INIT; - const char *first_slash = strchrnul(path, '/'); const char *to_copy = path; if (path == NULL) goto return_null; if (path[0] == '~') { + const char *first_slash = strchrnul(path, '/'); const char *username = path + 1; size_t username_len = first_slash - username; if (username_len == 0) {
-- 1.8.5.2.500.g8060133