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

From: Xiubo Li
Date: Fri May 16 2014 - 06:25:26 EST


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@xxxxxxxxx>
Signed-off-by: Xiubo Li <Li.Xiubo@xxxxxxxxxxxxx>
Cc: Nicolas Pitre <nico@xxxxxxxxxx>
Cc: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/