Revert "exec: avoid RLIMIT_STACK races with prlimit()"
Subsystems (2)
PATCH 1/1 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 <[email protected]>
Reported-by Tomáš Trnka <[email protected]>
Signed-off-by Kees Cook <[email protected]>
--- fs/exec.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-)
fs/exec.c +1 -6
@@ -1340,15 +1340,10 @@ 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);
Signature · 6 lines
2.7.4 -- Kees Cook Pixel Security