From 8626d723c5495ec9a276c8c13a22b374c421ba72 Mon Sep 17 00:00:00 2001 From: fanchaoting Date: Thu, 21 Mar 2013 09:15:30 +0800 Subject: pnfs-block: removing DM device maybe cause oops when call dev_remove commit 4376c94618c26225e69e17b7c91169c45a90b292 upstream. when pnfs block using device mapper,if umounting later,it maybe cause oops. we apply "1 + sizeof(bl_umount_request)" memory for msg->data, the memory maybe overflow when we do "memcpy(&dataptr [sizeof(bl_msg)], &bl_umount_request, sizeof(bl_umount_request))", because the size of bl_msg is more than 1 byte. Signed-off-by: fanchaoting Signed-off-by: Trond Myklebust [bwh: Backported to 3.2: - In dev_remove(), msg is a structure not a pointer to it] Signed-off-by: Ben Hutchings --- fs/nfs/blocklayout/blocklayoutdm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/nfs/blocklayout/blocklayoutdm.c b/fs/nfs/blocklayout/blocklayoutdm.c index d055c755807..7326e6ec0dc 100644 --- a/fs/nfs/blocklayout/blocklayoutdm.c +++ b/fs/nfs/blocklayout/blocklayoutdm.c @@ -52,7 +52,8 @@ static void dev_remove(dev_t dev) dprintk("Entering %s\n", __func__); memset(&msg, 0, sizeof(msg)); - msg.data = kzalloc(1 + sizeof(bl_umount_request), GFP_NOFS); + msg.len = sizeof(bl_msg) + bl_msg.totallen; + msg.data = kzalloc(msg.len, GFP_NOFS); if (!msg.data) goto out; @@ -63,7 +64,6 @@ static void dev_remove(dev_t dev) memcpy(msg.data, &bl_msg, sizeof(bl_msg)); dataptr = (uint8_t *) msg.data; memcpy(&dataptr[sizeof(bl_msg)], &bl_umount_request, sizeof(bl_umount_request)); - msg.len = sizeof(bl_msg) + bl_msg.totallen; add_wait_queue(&bl_wq, &wq); if (rpc_queue_upcall(bl_device_pipe->d_inode, &msg) < 0) { -- cgit v1.2.3-18-g5258