From 9126cb3186112f160a601e9a7eda29dd43227576 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ren=C3=A9=20Scharfe?= Date: Fri, 5 Apr 2024 12:53:23 +0200 Subject: [PATCH] apply: avoid fixed-size buffer in create_one_file() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Helped-by: Jeff King Signed-off-by: René Scharfe Signed-off-by: Junio C Hamano --- apply.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/apply.c b/apply.c 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,