From e7a7be8831b159b9a7331b34c3ec6915d4a72190 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Wed, 25 Jul 2007 21:34:53 -0700 Subject: [PATCH] git_mkstemp(): be careful not to overflow the path buffer. If user's TMPDIR is insanely long, return negative after setting errno to ENAMETOOLONG, pretending that the underlying mkstemp() choked on a temporary file path that is too long. Signed-off-by: Junio C Hamano --- diff.c | 2 +- path.c | 24 ++++++++++-------------- 2 files changed, 11 insertions(+), 15 deletions(-) diff --git a/diff.c b/diff.c index cd6b0c4e0..a5fc56bda 100644 --- a/diff.c +++ b/diff.c @@ -1695,7 +1695,7 @@ static void prep_temp_blob(struct diff_tempfile *temp, fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX"); if (fd < 0) - die("unable to create temp-file"); + die("unable to create temp-file: %s", strerror(errno)); if (write_in_full(fd, blob, size) != size) die("unable to write temp-file"); close(fd); diff --git a/path.c b/path.c index c4ce96236..dfff41f62 100644 --- a/path.c +++ b/path.c @@ -71,21 +71,17 @@ char *git_path(const char *fmt, ...) /* git_mkstemp() - create tmp file honoring TMPDIR variable */ int git_mkstemp(char *path, size_t len, const char *template) { - char *env, *pch = path; - - if ((env = getenv("TMPDIR")) == NULL) { - strcpy(pch, "/tmp/"); - len -= 5; - pch += 5; - } else { - size_t n = snprintf(pch, len, "%s/", env); - - len -= n; - pch += n; + const char *tmp; + size_t n; + + tmp = getenv("TMPDIR"); + if (!tmp) + tmp = "/tmp"; + n = snprintf(path, len, "%s/%s", tmp, template); + if (len <= n) { + errno = ENAMETOOLONG; + return -1; } - - strlcpy(pch, template, len); - return mkstemp(path); } -- 2.26.2