From: Vitaly Kuznetsov Date: Tue, 31 Mar 2015 18:16:41 +0000 (-0700) Subject: Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case X-Git-Tag: Ubuntu-snapdragon-4.4.0-1029.32~6733^2~5 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=797f88c987b02a8de8d4fac94ec2877b92ec35a2;p=mirror_ubuntu-zesty-kernel.git Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case balloon_wrk.num_pages is __u32 and it comes from host in struct dm_balloon where it is also __u32. We, however, use 'int' in balloon_up() and in case we happen to receive num_pages>INT_MAX request we'll end up allocating zero pages as 'num_pages < alloc_unit' check in alloc_balloon_pages() will pass. Change num_pages type to unsigned int. In real life ballooning request come with num_pages in [512, 32768] range so this is more a future-proof/cleanup. Reported-by: Laszlo Ersek Signed-off-by: Vitaly Kuznetsov Reviewed-by: Laszlo Ersek Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 4052ad8255fa..cb5b7dc9797f 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -1081,11 +1081,12 @@ static void free_balloon_pages(struct hv_dynmem_device *dm, -static int alloc_balloon_pages(struct hv_dynmem_device *dm, int num_pages, - struct dm_balloon_response *bl_resp, - int alloc_unit) +static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm, + unsigned int num_pages, + struct dm_balloon_response *bl_resp, + int alloc_unit) { - int i = 0; + unsigned int i = 0; struct page *pg; if (num_pages < alloc_unit) @@ -1132,8 +1133,8 @@ static int alloc_balloon_pages(struct hv_dynmem_device *dm, int num_pages, static void balloon_up(struct work_struct *dummy) { - int num_pages = dm_device.balloon_wrk.num_pages; - int num_ballooned = 0; + unsigned int num_pages = dm_device.balloon_wrk.num_pages; + unsigned int num_ballooned = 0; struct dm_balloon_response *bl_resp; int alloc_unit; int ret;