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 <gitster@pobox.com>
This commit is contained in:
Junio C Hamano 2007-07-25 21:34:53 -07:00
parent d58e8d34b0
commit e7a7be8831
2 changed files with 10 additions and 14 deletions

2
diff.c
View File

@ -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);

22
path.c
View File

@ -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;
const char *tmp;
size_t n;
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;
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);
}