From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Ellerman Date: Wed, 09 Feb 2005 09:58:07 +0000 Subject: [Patch] Fix oops in alloc_zeroed_user_highpage() when page is NULL Message-Id: <20050209205807.221d4591.michael@ellerman.id.au> List-Id: References: <20050108135636.6796419a.davem@davemloft.net> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Christoph Lameter Cc: davem@davemloft.net, hugh@veritas.com, akpm@osdl.org, linux-ia64@vger.kernel.org, torvalds@osdl.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Hi All, The generic and IA-64 versions of alloc_zeroed_user_highpage() don't check the return value from alloc_page_vma(). This can lead to an oops if we're OOM. This fixes my oops on PPC64, but I haven't got an IA-64 machine/compiler handy. Signed-off-by: Michael Ellerman diff -rN -p -u oombreakage-old/include/asm-ia64/page.h oombreakage-new/include/asm-ia64/page.h --- oombreakage-old/include/asm-ia64/page.h 2005-02-04 04:10:37.000000000 +1100 +++ oombreakage-new/include/asm-ia64/page.h 2005-02-09 20:53:37.000000000 +1100 @@ -79,7 +79,8 @@ do { \ #define alloc_zeroed_user_highpage(vma, vaddr) \ ({ \ struct page *page = alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO, vma, vaddr); \ - flush_dcache_page(page); \ + if (page) \ + flush_dcache_page(page); \ page; \ }) diff -rN -p -u oombreakage-old/include/linux/highmem.h oombreakage-new/include/linux/highmem.h --- oombreakage-old/include/linux/highmem.h 2005-02-09 20:22:41.000000000 +1100 +++ oombreakage-new/include/linux/highmem.h 2005-02-09 20:47:01.000000000 +1100 @@ -48,7 +48,9 @@ alloc_zeroed_user_highpage(struct vm_are { struct page *page = alloc_page_vma(GFP_HIGHUSER, vma, vaddr); - clear_user_highpage(page, vaddr); + if (page) + clear_user_highpage(page, vaddr); + return page; } #endif