From 5f2a2d5d423d5337a1392fa016ec23a8a4206006 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Fri, 6 Nov 2015 16:33:04 -0800 Subject: [PATCH] ipc,msg: drop dst nil validation in copy_msg d0edd8528362 ("ipc: convert invalid scenarios to use WARN_ON") relaxed the nil dst parameter check, originally being a full BUG_ON. However, this check seems quite unnecessary when the only purpose is for ceckpoint/restore (MSG_COPY flag): o The copy variable is set initially to nil, apparently as a way of ensuring that prepare_copy is previously called. Which is in fact done, unconditionally at the beginning of do_msgrcv. o There is no concurrency with 'copy' (stack allocated in do_msgrcv). Furthermore, any errors in 'copy' (and thus prepare_copy/copy_msg) should always handled by IS_ERR() family. Therefore remove this check altogether as it can never occur with the current users. Signed-off-by: Davidlohr Bueso Cc: Stanislav Kinsbursky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/msgutil.c | 1 - 1 file changed, 1 deletion(-) diff --git a/ipc/msgutil.c b/ipc/msgutil.c index 71f448e5e927..ed81aafd2392 100644 --- a/ipc/msgutil.c +++ b/ipc/msgutil.c @@ -123,7 +123,6 @@ struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) size_t len = src->m_ts; size_t alen; - WARN_ON(dst == NULL); if (src->m_ts > dst->m_ts) return ERR_PTR(-EINVAL); -- GitLab