[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1246244906.5759.5.camel@myhost>
Date: Mon, 29 Jun 2009 11:08:26 +0800
From: "Figo.zhang" <figo1802@...il.com>
To: Ingo Molnar <mingo@...e.hu>
Cc: lkml <linux-kernel@...r.kernel.org>, Andrew Morton <akpm@...l.org>
Subject: [PATCH]highmem_32.c: add argument pointer checking
It had better add argument pointer checking.
If any guys write driver want to alloc hightmem and pass a no-initial pointer,
it would be crashed.
Signed-off-by: Figo.zhang <figo1802@...il.com>
---
arch/x86/mm/highmem_32.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 58f621e..e52e1a9 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -31,6 +31,7 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
{
enum fixed_addresses idx;
unsigned long vaddr;
+ BUG_ON(!page);
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
pagefault_disable();
@@ -58,6 +59,9 @@ void kunmap_atomic(void *kvaddr, enum km_type type)
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
+ if(!kvaddr)
+ return;
+
/*
* Force other mappings to Oops if they'll try to access this pte
* without first remap it. Keeping stale mappings around is a bad idea
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists