Revert "ucounts: Increase ucounts reference counter before the security hook"

This reverts commit b493af3a66e067f93e5e03465507866ddeabff9e which is
commit bbb6d0f3e1feb43d663af089c7dedb23be6a04fb upstream.

The "original" commit 905ae01c4ae2 ("Add a reference to ucounts for each
cred"), should not have been applied to the 5.10.y tree, so revert it,
and the follow-on fixup patches as well.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/87v93k4bl6.fsf@disp2133
Cc: Alexey Gladkov <legion@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/cred.c b/kernel/cred.c
index 8c0983fa794a73a731358de72fa528c390cb2df5..098213d4a39c3de3636fa1e0cef0ba82484e14f1 100644 (file)
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -286,11 +286,11 @@ struct cred *prepare_creds(void)
        new->security = NULL;
 #endif
 
-       new->ucounts = get_ucounts(new->ucounts);
-       if (!new->ucounts)
+       if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
                goto error;
 
-       if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
+       new->ucounts = get_ucounts(new->ucounts);
+       if (!new->ucounts)
                goto error;
 
        validate_creds(new);
@@ -753,11 +753,11 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
 #ifdef CONFIG_SECURITY
        new->security = NULL;
 #endif
-       new->ucounts = get_ucounts(new->ucounts);
-       if (!new->ucounts)
+       if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
                goto error;
 
-       if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
+       new->ucounts = get_ucounts(new->ucounts);
+       if (!new->ucounts)
                goto error;
 
        put_cred(old);