Blame SOURCES/CVE-2023-0386.patch

9fd6a2
From 3bf90da39cf14660a11e3980451c757398bcf84e Mon Sep 17 00:00:00 2001
9fd6a2
From: Ryan Sullivan <rysulliv@redhat.com>
9fd6a2
Date: Wed, 15 Mar 2023 10:24:04 -0400
9fd6a2
Subject: [KPATCH CVE-2023-0386] kpatch fixes for CVE-2023-0386
9fd6a2
9fd6a2
Kernels:
9fd6a2
5.14.0-162.6.1.el9_1
9fd6a2
5.14.0-162.12.1.el9_1
9fd6a2
5.14.0-162.18.1.el9_1
9fd6a2
9fd6a2
9fd6a2
Kpatch-MR: https://gitlab.com/redhat/prdsc/rhel/src/kpatch/rhel-9/-/merge_requests/26
9fd6a2
Approved-by: Joe Lawrence (@joe.lawrence)
9fd6a2
Approved-by: Yannick Cote (@ycote1)
9fd6a2
Changes since last build:
9fd6a2
arches: x86_64 ppc64le
9fd6a2
copy_up.o: changed function: ovl_copy_up_one
9fd6a2
---------------------------
9fd6a2
9fd6a2
Modifications: none
9fd6a2
9fd6a2
commit 977edea04b2c1dd1dc51ae7a1dbf5b484c048045
9fd6a2
Author: Miklos Szeredi <mszeredi@redhat.com>
9fd6a2
Date:   Tue Jan 24 16:41:18 2023 +0100
9fd6a2
9fd6a2
    ovl: fail on invalid uid/gid mapping at copy up
9fd6a2
9fd6a2
    Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2165344
9fd6a2
    CVE: CVE-2023-0386
9fd6a2
9fd6a2
    If st_uid/st_gid doesn't have a mapping in the mounter's user_ns, then
9fd6a2
    copy-up should fail, just like it would fail if the mounter task was doing
9fd6a2
    the copy using "cp -a".
9fd6a2
9fd6a2
    There's a corner case where the "cp -a" would succeed but copy up fail: if
9fd6a2
    there's a mapping of the invalid uid/gid (65534 by default) in the user
9fd6a2
    namespace.  This is because stat(2) will return this value if the mapping
9fd6a2
    doesn't exist in the current user_ns and "cp -a" will in turn be able to
9fd6a2
    create a file with this uid/gid.
9fd6a2
9fd6a2
    This behavior would be inconsistent with POSIX ACL's, which return -1 for
9fd6a2
    invalid uid/gid which result in a failed copy.
9fd6a2
9fd6a2
    For consistency and simplicity fail the copy of the st_uid/st_gid are
9fd6a2
    invalid.
9fd6a2
9fd6a2
    Fixes: 459c7c565ac3 ("ovl: unprivieged mounts")
9fd6a2
    Cc: <stable@vger.kernel.org> # v5.11
9fd6a2
    Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
9fd6a2
    Reviewed-by: Christian Brauner <brauner@kernel.org>
9fd6a2
    Reviewed-by: Seth Forshee <sforshee@kernel.org>
9fd6a2
    (cherry picked from commit 4f11ada10d0ad3fd53e2bd67806351de63a4f9c3)
9fd6a2
9fd6a2
    Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
9fd6a2
9fd6a2
Signed-off-by: Ryan Sullivan <rysulliv@redhat.com>
9fd6a2
---
9fd6a2
 fs/overlayfs/copy_up.c | 4 ++++
9fd6a2
 1 file changed, 4 insertions(+)
9fd6a2
9fd6a2
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
9fd6a2
index 2846b943e80c..95b2173ab9bc 100644
9fd6a2
--- a/fs/overlayfs/copy_up.c
9fd6a2
+++ b/fs/overlayfs/copy_up.c
9fd6a2
@@ -886,6 +886,10 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
9fd6a2
 	if (err)
9fd6a2
 		return err;
9fd6a2
 
9fd6a2
+	if (!kuid_has_mapping(current_user_ns(), ctx.stat.uid) ||
9fd6a2
+	    !kgid_has_mapping(current_user_ns(), ctx.stat.gid))
9fd6a2
+		return -EOVERFLOW;
9fd6a2
+
9fd6a2
 	ctx.metacopy = ovl_need_meta_copy_up(dentry, ctx.stat.mode, flags);
9fd6a2
 
9fd6a2
 	if (parent) {
9fd6a2
-- 
9fd6a2
2.39.2
9fd6a2
9fd6a2