From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> commit 378f79cab12b669928f3a4037f023837ead2ce0c upstream "size + max" can have an arithmetic overflow when we're allocating: orig_src_addr = dma_alloc_coherent(dev, size + alignment, ... I've added a few checks to prevent that. Fixes: 13107c60681f ("misc: pci_endpoint_test: Add support to provide aligned buffer addresses") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> --- drivers/misc/pci_endpoint_test.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c index 9849bf183299..504fa680825d 100644 --- a/drivers/misc/pci_endpoint_test.c +++ b/drivers/misc/pci_endpoint_test.c @@ -226,6 +226,9 @@ static bool pci_endpoint_test_copy(struct pci_endpoint_test *test, size_t size) u32 src_crc32; u32 dst_crc32; + if (size > SIZE_MAX - alignment) + goto err; + orig_src_addr = dma_alloc_coherent(dev, size + alignment, &orig_src_phys_addr, GFP_KERNEL); if (!orig_src_addr) { @@ -311,6 +314,9 @@ static bool pci_endpoint_test_write(struct pci_endpoint_test *test, size_t size) size_t alignment = test->alignment; u32 crc32; + if (size > SIZE_MAX - alignment) + goto err; + orig_addr = dma_alloc_coherent(dev, size + alignment, &orig_phys_addr, GFP_KERNEL); if (!orig_addr) { @@ -369,6 +375,9 @@ static bool pci_endpoint_test_read(struct pci_endpoint_test *test, size_t size) size_t alignment = test->alignment; u32 crc32; + if (size > SIZE_MAX - alignment) + goto err; + orig_addr = dma_alloc_coherent(dev, size + alignment, &orig_phys_addr, GFP_KERNEL); if (!orig_addr) { -- 2.17.1