From: Nick Piggin <npiggin@suse.de>
Date: Wed, 14 Feb 2007 11:39:01 +0000 (+0100)
Subject: [PATCH] mincore: vma crossing fix
X-Git-Url: http://git.mmlx.us/?a=commitdiff_plain;h=e0a04cffa4e97e1e53625e40e70895c882e8972f;p=linux-edison.git

[PATCH] mincore: vma crossing fix

My mincore also forgot about crossing vmas.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/mincore.c b/mm/mincore.c
index 9c1d0a426e9..5efe0ded69b 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -77,8 +77,16 @@ static long do_mincore(unsigned long addr, unsigned char *vec, unsigned long pag
 	 * PTE array for our address.
 	 */
 	nr = PTRS_PER_PTE - ((addr >> PAGE_SHIFT) & (PTRS_PER_PTE-1));
-	if (nr > pages)
-		nr = pages;
+
+	/*
+	 * Don't overrun this vma
+	 */
+	nr = min(nr, (vma->vm_end - addr) >> PAGE_SHIFT);
+
+	/*
+	 * Don't return more than the caller asked for
+	 */
+	nr = min(nr, pages);
 
 	pgd = pgd_offset(vma->vm_mm, addr);
 	if (pgd_none_or_clear_bad(pgd))