diff --git a/fs/namei.c b/fs/namei.c index bb4a3e40e43269944523fc4f3987d4a556ca5f84..c784e8bb57a35c6fa272ece7303095887ef65e8a 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2243,14 +2243,16 @@ asmlinkage long sys_linkat(int olddfd, const char __user *oldname, int error; char * to; - if (flags != 0) + if ((flags & ~AT_SYMLINK_FOLLOW) != 0) return -EINVAL; to = getname(newname); if (IS_ERR(to)) return PTR_ERR(to); - error = __user_walk_fd(olddfd, oldname, 0, &old_nd); + error = __user_walk_fd(olddfd, oldname, + flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0, + &old_nd); if (error) goto exit; error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd); diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h index c52a63755fdd5b69e9bd63353b13e6aa82c738c9..996f5611cd59dc73ed9d01b2dec84f0708dcf7d9 100644 --- a/include/linux/fcntl.h +++ b/include/linux/fcntl.h @@ -29,6 +29,7 @@ #define AT_SYMLINK_NOFOLLOW 0x100 /* Do not follow symbolic links. */ #define AT_REMOVEDIR 0x200 /* Remove directory instead of unlinking file. */ +#define AT_SYMLINK_FOLLOW 0x400 /* Follow symbolic links. */ #ifdef __KERNEL__