SELinux: null-terminate context string in selinux_xfrm_sec_ctx_alloc

xfrm_audit_log() expects the context string to be null-terminated
which currently doesn't happen with user-supplied contexts.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index bd8d1ef40a90..ba715f40b658 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -216,7 +216,7 @@ static int selinux_xfrm_sec_ctx_alloc(struct xfrm_sec_ctx **ctxp,
                 return -ENOMEM;
 
         *ctxp = ctx = kmalloc(sizeof(*ctx) +
-                              uctx->ctx_len,
+                              uctx->ctx_len + 1,
                               GFP_KERNEL);
 
         if (!ctx)
@@ -229,6 +229,7 @@ static int selinux_xfrm_sec_ctx_alloc(struct xfrm_sec_ctx **ctxp,
         memcpy(ctx->ctx_str,
                uctx+1,
                ctx->ctx_len);
+        ctx->ctx_str[ctx->ctx_len] = 0;
         rc = security_context_to_sid(ctx->ctx_str,
                                      ctx->ctx_len,
                                      &ctx->ctx_sid);