From: Kees Cook Date: Tue, 12 Dec 2017 19:28:38 +0000 (-0800) Subject: Revert "exec: avoid RLIMIT_STACK races with prlimit()" X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=779f4e1c6c7c;p=openwrt%2Fstaging%2Fblogic.git Revert "exec: avoid RLIMIT_STACK races with prlimit()" This reverts commit 04e35f4495dd560db30c25efca4eecae8ec8c375. SELinux runs with secureexec for all non-"noatsecure" domain transitions, which means lots of processes end up hitting the stack hard-limit change that was introduced in order to fix a race with prlimit(). That race fix will need to be redesigned. Reported-by: Laura Abbott Reported-by: Tomáš Trnka Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Linus Torvalds --- diff --git a/fs/exec.c b/fs/exec.c index 156f56acfe8e..5688b5e1b937 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1339,15 +1339,10 @@ void setup_new_exec(struct linux_binprm * bprm) * avoid bad behavior from the prior rlimits. This has to * happen before arch_pick_mmap_layout(), which examines * RLIMIT_STACK, but after the point of no return to avoid - * races from other threads changing the limits. This also - * must be protected from races with prlimit() calls. + * needing to clean up the change on failure. */ - task_lock(current->group_leader); if (current->signal->rlim[RLIMIT_STACK].rlim_cur > _STK_LIM) current->signal->rlim[RLIMIT_STACK].rlim_cur = _STK_LIM; - if (current->signal->rlim[RLIMIT_STACK].rlim_max > _STK_LIM) - current->signal->rlim[RLIMIT_STACK].rlim_max = _STK_LIM; - task_unlock(current->group_leader); } arch_pick_mmap_layout(current->mm);