From: Oleg Nesterov Date: Wed, 26 May 2010 21:43:21 +0000 (-0700) Subject: check_unshare_flags: kill the bogus CLONE_SIGHAND/sig->count check X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=6e1be45aa6ba6a36c0312f65ecf311135c73001d;p=openwrt%2Fstaging%2Fblogic.git check_unshare_flags: kill the bogus CLONE_SIGHAND/sig->count check check_unshare_flags(CLONE_SIGHAND) adds CLONE_THREAD to *flags_ptr if the task is multithreaded to ensure unshare_thread() will fail. Not only this is a bit strange way to return the error, this is absolutely meaningless. If signal->count > 1 then sighand->count must be also > 1, and unshare_sighand() will fail anyway. In fact, all CLONE_THREAD/SIGHAND/VM checks inside sys_unshare() do not look right. Fortunately this code doesn't really work anyway. Signed-off-by: Oleg Nesterov Cc: Balbir Singh Acked-by: Roland McGrath Cc: Veaceslav Falico Cc: Stanislaw Gruszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/kernel/fork.c b/kernel/fork.c index 7701470ea1b8..40cd099cfc1b 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1517,14 +1517,6 @@ static void check_unshare_flags(unsigned long *flags_ptr) if (*flags_ptr & CLONE_VM) *flags_ptr |= CLONE_SIGHAND; - /* - * If unsharing signal handlers and the task was created - * using CLONE_THREAD, then must unshare the thread - */ - if ((*flags_ptr & CLONE_SIGHAND) && - (atomic_read(¤t->signal->count) > 1)) - *flags_ptr |= CLONE_THREAD; - /* * If unsharing namespace, must also unshare filesystem information. */