René Scharfe <l.s.r@xxxxxx> writes: > The value of PATH_MAX is platform-dependent, so it's easy to exceed when > doing cross-platform development. It's also not a hard limit on most > operating systems, not even on Windows. Further reading: > > https://insanecoding.blogspot.com/2007/11/pathmax-simply-isnt.html > > So using a fixed buffer is not a good idea, and writing to it without > checking is dangerous. Here's a fix: > > -- >8 -- > Subject: [PATCH] merge-recursive: use xstrdup() instead of fixed buffer > > Paths can be longer than PATH_MAX. Avoid a buffer overrun in > check_dir_renamed() by using xstrdup() to make a private copy safely. > > Signed-off-by: Rene Scharfe <l.s.r@xxxxxx> > --- Thanks. Makes sense. > merge-recursive.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/merge-recursive.c b/merge-recursive.c > index ac27abbd4c..db708176c5 100644 > --- a/merge-recursive.c > +++ b/merge-recursive.c > @@ -2211,18 +2211,18 @@ static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs, > static struct dir_rename_entry *check_dir_renamed(const char *path, > struct hashmap *dir_renames) > { > - char temp[PATH_MAX]; > + char *temp = xstrdup(path); > char *end; > - struct dir_rename_entry *entry; > + struct dir_rename_entry *entry = NULL;; > > - strcpy(temp, path); > while ((end = strrchr(temp, '/'))) { > *end = '\0'; > entry = dir_rename_find_entry(dir_renames, temp); > if (entry) > - return entry; > + break; > } > - return NULL; > + free(temp); > + return entry; > } > > static void compute_collisions(struct hashmap *collisions,
