From 98c50f93fe494be5547188813c367299db80dbc5 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 13 Aug 2016 23:23:48 +0200 Subject: cp: fix -i for POSIX mode. Closes 9106 Signed-off-by: Denys Vlasenko --- libbb/copy_file.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'libbb') diff --git a/libbb/copy_file.c b/libbb/copy_file.c index 7801b58c7..23c0f8320 100644 --- a/libbb/copy_file.c +++ b/libbb/copy_file.c @@ -296,11 +296,16 @@ int FAST_FUNC copy_file(const char *source, const char *dest, int flags) if (!S_ISREG(source_stat.st_mode)) new_mode = 0666; - // POSIX way is a security problem versus (sym)link attacks - if (!ENABLE_FEATURE_NON_POSIX_CP) { - dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, new_mode); - } else { /* safe way: */ + if (ENABLE_FEATURE_NON_POSIX_CP || (flags & FILEUTILS_INTERACTIVE)) { + /* + * O_CREAT|O_EXCL: require that file did not exist before creation + */ dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode); + } else { /* POSIX, and not "cp -i" */ + /* + * O_CREAT|O_TRUNC: create, or truncate (security problem versus (sym)link attacks) + */ + dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, new_mode); } if (dst_fd == -1) { ovr = ask_and_unlink(dest, flags); -- cgit v1.2.3