udmabuf: fix a buf size overflow issue during udmabuf creation

by casting size_limit_mb to u64  when calculate pglimit.

Signed-off-by: Xiaogang Chen<Xiaogang.Chen@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250321164126.329638-1-xiaogang.chen@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>

diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
index cc7398cc17d67fca0634e763534901f8e6b454f8..e74e36a8ecda21423a8b4602e3b7b696cf0168eb 100644 (file)
--- a/drivers/dma-buf/udmabuf.c
+++ b/drivers/dma-buf/udmabuf.c
@@ -393,7 +393,7 @@ static long udmabuf_create(struct miscdevice *device,
        if (!ubuf)
                return -ENOMEM;
 
-       pglimit = (size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
+       pglimit = ((u64)size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
        for (i = 0; i < head->count; i++) {
                pgoff_t subpgcnt;