From: Hugh Dickins Date: Thu, 4 Aug 2005 20:07:09 +0000 (-0700) Subject: [PATCH] fix VmSize and VmData after mremap X-Git-Tag: v2.6.13-rc6~48 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1c5ad84516ae7ea4ec868436a910a6bd8d20215a;p=linux-2.6 [PATCH] fix VmSize and VmData after mremap mremap's move_vma is applying __vm_stat_account to the old vma which may have already been freed: move it to just before the do_munmap. mremapping to and fro with CONFIG_DEBUG_SLAB=y showed /proc//status VmSize and VmData wrapping just like in kernel bugzilla #4842, and fixed by this patch - worth including in 2.6.13, though not yet confirmed that it fixes that specific report from Frank van Maarseveen. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/mremap.c b/mm/mremap.c index ec7238a78f..fc45dc9a61 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -229,6 +229,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, * since do_munmap() will decrement it by old_len == new_len */ mm->total_vm += new_len >> PAGE_SHIFT; + __vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT); if (do_munmap(mm, old_addr, old_len) < 0) { /* OOM: unable to split vma, just get accounts right */ @@ -243,7 +244,6 @@ static unsigned long move_vma(struct vm_area_struct *vma, vma->vm_next->vm_flags |= VM_ACCOUNT; } - __vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT); if (vm_flags & VM_LOCKED) { mm->locked_vm += new_len >> PAGE_SHIFT; if (new_len > old_len)