From 6d6f3328422a3bc56b0d8dd026a5de845d2abfa7 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Tue, 22 Jul 2014 21:20:01 +0900 Subject: [PATCH] commoncap: don't alloc the credential unless needed in cap_task_prctl In function cap_task_prctl(), we would allocate a credential unconditionally and then check if we support the requested function. If not we would release this credential with abort_creds() by using RCU method. But on some archs such as powerpc, the sys_prctl is heavily used to get/set the floating point exception mode. So the unnecessary allocating/releasing of credential not only introduce runtime overhead but also do cause OOM due to the RCU implementation. This patch removes abort_creds() from cap_task_prctl() by calling prepare_creds() only when we need to modify it. Reported-by: Kevin Hao Signed-off-by: Tetsuo Handa Reviewed-by: Paul Moore Acked-by: Serge E. Hallyn Reviewed-by: Kees Cook Signed-off-by: James Morris --- Reading git-format-patch failed