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authorKevin Grandemange <kevin.grandemange@allegrodvt.com>2020-03-12 15:41:45 +0000
committerChristoph Hellwig <hch@lst.de>2020-03-16 10:43:02 +0100
commit286c21de32b904131f8cf6a36ce40b8b0c9c5da3 (patch)
treef49e515ea7dae21ce3270d3fa1160dcc5dd9ae5a /kernel/dma/coherent.c
parent11a48a5a18c63fd7621bb050228cebf13566e4d8 (diff)
dma-coherent: fix integer overflow in the reserved-memory dma allocation
pageno is an int and the PAGE_SHIFT shift is done on an int, overflowing if the memory is bigger than 2G This can be reproduced using for example a reserved-memory of 4G reserved-memory { #address-cells = <2>; #size-cells = <2>; ranges; reserved_dma: buffer@0 { compatible = "shared-dma-pool"; no-map; reg = <0x5 0x00000000 0x1 0x0>; }; }; Signed-off-by: Kevin Grandemange <kevin.grandemange@allegrodvt.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel/dma/coherent.c')
-rw-r--r--kernel/dma/coherent.c13
1 files changed, 7 insertions, 6 deletions
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index 551b0eb7028a..2a0c4985f38e 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -134,7 +134,7 @@ static void *__dma_alloc_from_coherent(struct device *dev,
spin_lock_irqsave(&mem->spinlock, flags);
- if (unlikely(size > (mem->size << PAGE_SHIFT)))
+ if (unlikely(size > ((dma_addr_t)mem->size << PAGE_SHIFT)))
goto err;
pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
@@ -144,8 +144,9 @@ static void *__dma_alloc_from_coherent(struct device *dev,
/*
* Memory was found in the coherent area.
*/
- *dma_handle = dma_get_device_base(dev, mem) + (pageno << PAGE_SHIFT);
- ret = mem->virt_base + (pageno << PAGE_SHIFT);
+ *dma_handle = dma_get_device_base(dev, mem) +
+ ((dma_addr_t)pageno << PAGE_SHIFT);
+ ret = mem->virt_base + ((dma_addr_t)pageno << PAGE_SHIFT);
spin_unlock_irqrestore(&mem->spinlock, flags);
memset(ret, 0, size);
return ret;
@@ -194,7 +195,7 @@ static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
int order, void *vaddr)
{
if (mem && vaddr >= mem->virt_base && vaddr <
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+ (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
unsigned long flags;
@@ -238,10 +239,10 @@ static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
struct vm_area_struct *vma, void *vaddr, size_t size, int *ret)
{
if (mem && vaddr >= mem->virt_base && vaddr + size <=
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+ (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
unsigned long off = vma->vm_pgoff;
int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
- int user_count = vma_pages(vma);
+ unsigned long user_count = vma_pages(vma);
int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
*ret = -ENXIO;