apply: avoid fixed-size buffer in create_one_file()
PATH_MAX is not always a hard limit and 'path' in create_one_file() could be longer -- it's taken from the patch file and allocated dynamically. Allocate the name of the temporary file on the heap as well instead of using a fixed-size buffer to avoid that arbitrary limit. Resist the temptation of using the more convenient mkpath() to avoid introducing a dependency on a static variable deep inside the apply machinery. Take care to work around (arguably buggy) implementations of free(3) that modify errno, by calling it only after using the errno value. Suggested-by: Jeff King <peff@peff.net> Helped-by: Jeff King <peff@peff.net> Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe committed
Apr 5, 2024 at 12:53 UTC
9126cb3186112f160a601e9a7eda29dd43227576
1 file changed
+9
-6
apply.c
+9
-6
index 7608e3301c..925dbde713 100644
--- a/apply.c
+++ b/apply.c
@@ -4430,6 +4430,7 @@ static int create_one_file(struct apply_state *state,
const char *buf,
unsigned long size)
{
+ char *newpath = NULL;
int res;
if (state->cached)
@@ -4491,24 +4492,26 @@ static int create_one_file(struct apply_state *state,
unsigned int nr = getpid();
for (;;) {
- char newpath[PATH_MAX];
- mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
+ newpath = mkpathdup("%s~%u", path, nr);
res = try_create_file(state, newpath, mode, buf, size);
if (res < 0)
- return -1;
+ goto out;
if (!res) {
if (!rename(newpath, path))
- return 0;
+ goto out;
unlink_or_warn(newpath);
break;
}
if (errno != EEXIST)
break;
++nr;
+ FREE_AND_NULL(newpath);
}
}
- return error_errno(_("unable to write file '%s' mode %o"),
- path, mode);
+ res = error_errno(_("unable to write file '%s' mode %o"), path, mode);
+out:
+ free(newpath);
+ return res;
}
static int add_conflicted_stages_file(struct apply_state *state,