[PATCH v3] arm: ioremap: Fix static vm area boundary check.

Xiubo Li Li.Xiubo at freescale.com
Fri May 16 02:35:20 PDT 2014


For each vmalloc area, there is one guard page at the end of it.
so the vm->size = PAGE_ALIGN(offset + request size) + guard page size.

Signed-off-by: Richard Lee <superlibj8301 at gmail.com>
Signed-off-by: Xiubo Li <Li.Xiubo at freescale.com>
Cc: Nicolas Pitre <nico at linaro.org>
Cc: Santosh Shilimkar <santosh.shilimkar at ti.com>
Cc: Joonsoo Kim <iamjoonsoo.kim at lge.com>
---
 arch/arm/mm/ioremap.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index be69333..758e8f7 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -49,14 +49,18 @@ static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
 	struct vm_struct *vm;
 
 	list_for_each_entry(svm, &static_vmlist, list) {
+		phys_addr_t paddr_end, phys_addr_end;
+
 		vm = &svm->vm;
 		if (!(vm->flags & VM_ARM_STATIC_MAPPING))
 			continue;
 		if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
 			continue;
 
-		if (vm->phys_addr > paddr ||
-			paddr + size - 1 > vm->phys_addr + vm->size - 1)
+		/* The PAGE_SIZE here is vmalloc area's guard page */
+		phys_addr_end = vm->phys_addr + vm->size - PAGE_SIZE - 1;
+		paddr_end = paddr + size - 1;
+		if (vm->phys_addr > paddr || paddr_end > phys_addr_end)
 			continue;
 
 		return svm;
-- 
1.8.4




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