cp: detect and prevent infinite recursion
diff --git a/libbb/copy_file.c b/libbb/copy_file.c
index a86e497..b70d7b5 100644
--- a/libbb/copy_file.c
+++ b/libbb/copy_file.c
@@ -114,6 +114,7 @@
if (S_ISDIR(source_stat.st_mode)) {
DIR *dp;
+ const char *existing_name;
struct dirent *d;
mode_t saved_umask = 0;
@@ -122,6 +123,15 @@
return -1;
}
+ /* Did we ever create source ourself before? */
+ existing_name = is_in_ino_dev_hashtable(&source_stat);
+ if (existing_name) {
+ /* We did! it's a recursion! man the lifeboats... */
+ bb_error_msg("recursion detected, omitting directory '%s'",
+ existing_name);
+ return -1;
+ }
+
/* Create DEST */
if (dest_exists) {
if (!S_ISDIR(dest_stat.st_mode)) {
@@ -143,7 +153,15 @@
return -1;
}
umask(saved_umask);
+ /* need stat info for add_to_ino_dev_hashtable */
+ if (lstat(dest, &dest_stat) < 0) {
+ bb_perror_msg("cannot stat '%s'", dest);
+ return -1;
+ }
}
+ /* remember (dev,inode) of each created dir.
+ * NULL: name is not remembered */
+ add_to_ino_dev_hashtable(&dest_stat, NULL);
/* Recursively copy files in SOURCE */
dp = opendir(source);
@@ -169,8 +187,8 @@
if (!dest_exists
&& chmod(dest, source_stat.st_mode & ~saved_umask) < 0
) {
- bb_perror_msg("cannot change permissions of '%s'", dest);
- retval = -1;
+ bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
+ /* retval = -1; - WRONG! copy *WAS* made */
}
goto preserve_mode_ugid_time;
}
@@ -197,7 +215,7 @@
}
if (S_ISREG(source_stat.st_mode)
- /* Huh? DEREF uses stat, which never returns links! */
+ /* DEREF uses stat, which never returns S_ISLNK() == true. */
/* || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) */
) {
int src_fd;
@@ -269,14 +287,13 @@
#endif
if (bb_copyfd_eof(src_fd, dst_fd) == -1)
retval = -1;
+ /* Ok, writing side I can understand... */
if (close(dst_fd) < 0) {
bb_perror_msg("cannot close '%s'", dest);
retval = -1;
}
- if (close(src_fd) < 0) {
- bb_perror_msg("cannot close '%s'", source);
- retval = -1;
- }
+ /* ...but read size is already checked by bb_copyfd_eof */
+ close(src_fd);
goto preserve_mode_ugid_time;
}
@@ -289,18 +306,18 @@
return ovr;
}
if (S_ISLNK(source_stat.st_mode)) {
- char *lpath;
-
- lpath = xmalloc_readlink_or_warn(source);
- if (lpath && symlink(lpath, dest) < 0) {
- bb_perror_msg("cannot create symlink '%s'", dest);
+ char *lpath = xmalloc_readlink_or_warn(source);
+ if (lpath) {
+ int r = symlink(lpath, dest);
free(lpath);
- return -1;
+ if (r < 0) {
+ bb_perror_msg("cannot create symlink '%s'", dest);
+ return -1;
+ }
+ if (flags & FILEUTILS_PRESERVE_STATUS)
+ if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
+ bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
}
- free(lpath);
- if (flags & FILEUTILS_PRESERVE_STATUS)
- if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
- bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
/* _Not_ jumping to preserve_mode_ugid_time:
* symlinks don't have those */
return 0;
@@ -327,6 +344,7 @@
times.actime = source_stat.st_atime;
times.modtime = source_stat.st_mtime;
+ /* BTW, utimes sets usec-precision time - just FYI */
if (utime(dest, ×) < 0)
bb_perror_msg("cannot preserve %s of '%s'", "times", dest);
if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {