From 9f86ddc9652247233f32b241a79d5aa4fb9d4afa Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Tue, 26 Nov 2024 09:16:31 +1100 Subject: [PATCH] disallow ../ elements in relpath for secure_relative_open CVE: CVE-2024-12086 Upstream-Status: Backport [https://git.samba.org/?p=rsync.git;a=commit;h=9f86ddc9652247233f32b241a79d5aa4fb9d4afa] Signed-off-by: Archana Polampalli --- syscall.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/syscall.c b/syscall.c index cffc814b..081357bb 100644 --- a/syscall.c +++ b/syscall.c @@ -716,6 +716,8 @@ int do_open_nofollow(const char *pathname, int flags) must be a relative path, and the relpath must not contain any elements in the path which follow symlinks (ie. like O_NOFOLLOW, but applies to all path components, not just the last component) + + The relpath must also not contain any ../ elements in the path */ int secure_relative_open(const char *basedir, const char *relpath, int flags, mode_t mode) { @@ -724,6 +726,11 @@ int secure_relative_open(const char *basedir, const char *relpath, int flags, mo errno = EINVAL; return -1; } + if (strncmp(relpath, "../", 3) == 0 || strstr(relpath, "/../")) { + // no ../ elements allowed in the relpath + errno = EINVAL; + return -1; + } #if !defined(O_NOFOLLOW) || !defined(O_DIRECTORY) // really old system, all we can do is live with the risks -- 2.40.0