The functions read_directory_recursive() and treat_leading_path() both
use buffers sized to fit PATH_MAX characters. The latter can be made to
overrun its buffer, e.g. like this:
$ a=0123456789abcdef
$ a=$a$a$a$a$a$a$a$a
$ a=$a$a$a$a$a$a$a$a
$ a=$a$a$a$a$a$a$a$a
$ git add $a/a
Instead of trying to add a check and potentionally forgetting to address
similar cases, convert the involved functions and their helpers to use
struct strbuf. The patch is suprisingly large because the helpers
treat_path() and treat_one_path() modify the buffer as well and thus
need to be converted, too.
Signed-off-by: Rene Scharfe <rene.scharfe@xxxxxxxxxxxxxx>
---
dir.c | 76 ++++++++++++++++++++++++++++++++---------------------------------
1 file changed, 37 insertions(+), 39 deletions(-)
diff --git a/dir.c b/dir.c
index e98760c..c6a98cc 100644
--- a/dir.c
+++ b/dir.c
@@ -873,14 +873,14 @@ enum path_treatment {
};
static enum path_treatment treat_one_path(struct dir_struct *dir,
- char *path, int *len,
+ struct strbuf *path,
const struct path_simplify *simplify,
int dtype, struct dirent *de)
{
- int exclude = excluded(dir, path, &dtype);
+ int exclude = excluded(dir, path->buf, &dtype);
if (exclude && (dir->flags & DIR_COLLECT_IGNORED)
- && exclude_matches_pathspec(path, *len, simplify))
- dir_add_ignored(dir, path, *len);
+ && exclude_matches_pathspec(path->buf, path->len, simplify))
+ dir_add_ignored(dir, path->buf, path->len);
/*
* Excluded? If we don't explicitly want to show
@@ -890,7 +890,7 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
return path_ignored;
if (dtype == DT_UNKNOWN)
- dtype = get_dtype(de, path, *len);
+ dtype = get_dtype(de, path->buf, path->len);
/*
* Do we want to see just the ignored files?
@@ -907,9 +907,8 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
default:
return path_ignored;
case DT_DIR:
- memcpy(path + *len, "/", 2);
- (*len)++;
- switch (treat_directory(dir, path, *len, simplify)) {
+ strbuf_addch(path, '/');
+ switch (treat_directory(dir, path->buf, path->len, simplify)) {
case show_directory:
if (exclude != !!(dir->flags
& DIR_SHOW_IGNORED))
@@ -930,26 +929,21 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
static enum path_treatment treat_path(struct dir_struct *dir,
struct dirent *de,
- char *path, int path_max,
+ struct strbuf *path,
int baselen,
- const struct path_simplify *simplify,
- int *len)
+ const struct path_simplify *simplify)
{
int dtype;
if (is_dot_or_dotdot(de->d_name) || !strcmp(de->d_name, ".git"))
return path_ignored;
- *len = strlen(de->d_name);
- /* Ignore overly long pathnames! */
- if (*len + baselen + 8 > path_max)
- return path_ignored;
- memcpy(path + baselen, de->d_name, *len + 1);
- *len += baselen;
- if (simplify_away(path, *len, simplify))
+ strbuf_setlen(path, baselen);
+ strbuf_addstr(path, de->d_name);
+ if (simplify_away(path->buf, path->len, simplify))
return path_ignored;
dtype = DTYPE(de);
- return treat_one_path(dir, path, len, simplify, dtype, de);
+ return treat_one_path(dir, path, simplify, dtype, de);
}
/*
@@ -969,19 +963,19 @@ static int read_directory_recursive(struct dir_struct *dir,
DIR *fdir = opendir(*base ? base : ".");
int contents = 0;
struct dirent *de;
- char path[PATH_MAX + 1];
+ struct strbuf path = STRBUF_INIT;
if (!fdir)
return 0;
- memcpy(path, base, baselen);
+ strbuf_add(&path, base, baselen);
while ((de = readdir(fdir)) != NULL) {
- int len;
- switch (treat_path(dir, de, path, sizeof(path),
- baselen, simplify, &len)) {
+ switch (treat_path(dir, de, &path, baselen, simplify)) {
case path_recurse:
- contents += read_directory_recursive(dir, path, len, 0, simplify);
+ contents += read_directory_recursive(dir, path.buf,
+ path.len, 0,
+ simplify);
continue;
case path_ignored:
continue;
@@ -992,10 +986,11 @@ static int read_directory_recursive(struct dir_struct *dir,
if (check_only)
goto exit_early;
else
- dir_add_name(dir, path, len);
+ dir_add_name(dir, path.buf, path.len);
}
exit_early:
closedir(fdir);
+ strbuf_release(&path);
return contents;
}
@@ -1058,8 +1053,8 @@ static int treat_leading_path(struct dir_struct *dir,
const char *path, int len,
const struct path_simplify *simplify)
{
- char pathbuf[PATH_MAX];
- int baselen, blen;
+ struct strbuf sb = STRBUF_INIT;
+ int baselen, rc = 0;
const char *cp;
while (len && path[len - 1] == '/')
@@ -1074,19 +1069,22 @@ static int treat_leading_path(struct dir_struct *dir,
baselen = len;
else
baselen = cp - path;
- memcpy(pathbuf, path, baselen);
- pathbuf[baselen] = '\0';
- if (!is_directory(pathbuf))
- return 0;
- if (simplify_away(pathbuf, baselen, simplify))
- return 0;
- blen = baselen;
- if (treat_one_path(dir, pathbuf, &blen, simplify,
+ strbuf_setlen(&sb, 0);
+ strbuf_add(&sb, path, baselen);
+ if (!is_directory(sb.buf))
+ break;
+ if (simplify_away(sb.buf, sb.len, simplify))
+ break;
+ if (treat_one_path(dir, &sb, simplify,
DT_DIR, NULL) == path_ignored)
- return 0; /* do not recurse into it */
- if (len <= baselen)
- return 1; /* finished checking */
+ break; /* do not recurse into it */
+ if (len <= baselen) {
+ rc = 1;
+ break; /* finished checking */
+ }
}
+ strbuf_release(&sb);
+ return rc;
}
int read_directory(struct dir_struct *dir, const char *path, int len, const char **pathspec)
--
1.7.10
--
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