From: Jann Horn Date: Wed, 10 Apr 2019 16:55:58 +0000 (-0700) Subject: LSM: SafeSetID: fix userns handling in securityfs X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=71a98971b932174e121bc19056475c601598132f;p=openwrt%2Fstaging%2Fblogic.git LSM: SafeSetID: fix userns handling in securityfs Looking at current_cred() in write handlers is bad form, stop doing that. Also, let's just require that the write is coming from the initial user namespace. Especially SAFESETID_WHITELIST_FLUSH requires privilege over all namespaces, and SAFESETID_WHITELIST_ADD should probably require it as well. Signed-off-by: Jann Horn Signed-off-by: Micah Morton --- diff --git a/security/safesetid/securityfs.c b/security/safesetid/securityfs.c index 90784a8d950a..77d301f0ff7a 100644 --- a/security/safesetid/securityfs.c +++ b/security/safesetid/securityfs.c @@ -59,8 +59,8 @@ static int parse_policy_line( if (ret) return ret; - *parent = make_kuid(current_user_ns(), parsed_parent); - *child = make_kuid(current_user_ns(), parsed_child); + *parent = make_kuid(file->f_cred->user_ns, parsed_parent); + *child = make_kuid(file->f_cred->user_ns, parsed_child); if (!uid_valid(*parent) || !uid_valid(*child)) return -EINVAL; @@ -92,7 +92,7 @@ static ssize_t safesetid_file_write(struct file *file, kuid_t child; int ret; - if (!ns_capable(current_user_ns(), CAP_MAC_ADMIN)) + if (!file_ns_capable(file, &init_user_ns, CAP_MAC_ADMIN)) return -EPERM; if (*ppos != 0)