From: Laurent Dufour Date: Fri, 8 Sep 2017 23:13:12 +0000 (-0700) Subject: mm/memory.c: fix mem_cgroup_oom_disable() call missing X-Git-Tag: v4.12.13~11 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=846073130799031e6e1e8a692d96438105c4edf6;p=thirdparty%2Fkernel%2Fstable.git mm/memory.c: fix mem_cgroup_oom_disable() call missing commit de0c799bba2610a8e1e9a50d76a28614520a4cd4 upstream. 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@linux.vnet.ibm.com Fixes: bae473a423f6 ("mm: introduce fault_env") Signed-off-by: Laurent Dufour Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- diff --git a/mm/memory.c b/mm/memory.c index 9e50ffcf96390..0a98a1a55dfa7 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3843,6 +3843,11 @@ int handle_mm_fault(struct vm_area_struct *vma, unsigned long address, /* 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. @@ -3850,11 +3855,6 @@ int handle_mm_fault(struct vm_area_struct *vma, unsigned long address, 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