From: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx> Subject: mm/memory.c: fix mem_cgroup_oom_disable() call missing Seen while reading the code, in handle_mm_fault(), in the case arch_vma_access_permitted() is failing the call to mem_cgroup_oom_disable() is not made. To fix that, move the call to mem_cgroup_oom_enable() after calling arch_vma_access_permitted() as it should not have entered the memcg OOM. Link: http://lkml.kernel.org/r/1504625439-31313-1-git-send-email-ldufour@xxxxxxxxxxxxxxxxxx Fixes: bae473a423f6 ("mm: introduce fault_env") Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff -puN mm/memory.c~mm-fix-mem_cgroup_oom_disable-call-missing mm/memory.c --- a/mm/memory.c~mm-fix-mem_cgroup_oom_disable-call-missing +++ a/mm/memory.c @@ -4053,6 +4053,11 @@ int handle_mm_fault(struct vm_area_struc /* do counter updates before entering really critical section. */ check_sync_rss_stat(current); + if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE, + flags & FAULT_FLAG_INSTRUCTION, + flags & FAULT_FLAG_REMOTE)) + return VM_FAULT_SIGSEGV; + /* * Enable the memcg OOM handling for faults triggered in user * space. Kernel faults are handled more gracefully. @@ -4060,11 +4065,6 @@ int handle_mm_fault(struct vm_area_struc if (flags & FAULT_FLAG_USER) mem_cgroup_oom_enable(); - if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE, - flags & FAULT_FLAG_INSTRUCTION, - flags & FAULT_FLAG_REMOTE)) - return VM_FAULT_SIGSEGV; - if (unlikely(is_vm_hugetlb_page(vma))) ret = hugetlb_fault(vma->vm_mm, vma, address, flags); else _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
