diff options
author | Denis Vlasenko <vda.linux@googlemail.com> | 2007-08-27 20:51:30 +0400 |
---|---|---|
committer | Denis Vlasenko <vda.linux@googlemail.com> | 2007-08-27 20:51:30 +0400 |
commit | 8a5fab6333eee874e0675a89937d31b9ae3a7345 (patch) | |
tree | 67e8f21b25ccc1ab4d73f3dc5136854e6a432f91 /libbb/copy_file.c | |
parent | 512499c8cab30684785c6b116abbb7c868ac5be9 (diff) |
cp: detect and prevent infinite recursion
Diffstat (limited to 'libbb/copy_file.c')
-rw-r--r-- | libbb/copy_file.c | 52 |
1 files changed, 35 insertions, 17 deletions
diff --git a/libbb/copy_file.c b/libbb/copy_file.c index a86e497f0..b70d7b5e0 100644 --- a/libbb/copy_file.c +++ b/libbb/copy_file.c @@ -114,6 +114,7 @@ int copy_file(const char *source, const char *dest, int flags) 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 @@ int copy_file(const char *source, const char *dest, int flags) 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 @@ int copy_file(const char *source, const char *dest, int flags) 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 @@ int copy_file(const char *source, const char *dest, int flags) 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 @@ int copy_file(const char *source, const char *dest, int flags) } 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 @@ int copy_file(const char *source, const char *dest, int flags) #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 @@ int copy_file(const char *source, const char *dest, int flags) 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 @@ int copy_file(const char *source, const char *dest, int flags) 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) { |