From 677a50e8e931741a174f45d9cae981253dfae3ff Mon Sep 17 00:00:00 2001 From: Jan Synacek Date: Wed, 29 Mar 2017 08:25:52 +0200 Subject: [PATCH] basic: forbid rm_rf() to remove paths ending with ".." (#5653) Fixes: #5644(cherry picked from commit ab883125704b9310dcdfcf7451a27e85609da76c) --- src/basic/rm-rf.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/src/basic/rm-rf.c b/src/basic/rm-rf.c index 08497af729..bdaca264ff 100644 --- a/src/basic/rm-rf.c +++ b/src/basic/rm-rf.c @@ -187,6 +187,13 @@ int rm_rf(const char *path, RemoveFlags flags) { return -EPERM; } + /* Another safe-check. Removing "/path/.." could easily remove entire root as well. + * It's especially easy to do using globs in tmpfiles, like "/path/.*", which the glob() + * function expands to both "/path/." and "/path/..". + * Return -EINVAL to be consistent with rmdir("/path/."). */ + if (endswith(path, "/..") || endswith(path, "/../")) + return -EINVAL; + if ((flags & (REMOVE_SUBVOLUME|REMOVE_ROOT|REMOVE_PHYSICAL)) == (REMOVE_SUBVOLUME|REMOVE_ROOT|REMOVE_PHYSICAL)) { /* Try to remove as subvolume first */ r = btrfs_subvol_remove(path, BTRFS_REMOVE_RECURSIVE|BTRFS_REMOVE_QUOTA);