* [PATCH] xen/grants: prevent integer overflow in gnttab_dma_alloc_pages()
@ 2022-09-01 15:35 Dan Carpenter
2022-09-02 7:01 ` Juergen Gross
0 siblings, 1 reply; 2+ messages in thread
From: Dan Carpenter @ 2022-09-01 15:35 UTC (permalink / raw)
To: Juergen Gross
Cc: Stefano Stabellini, Oleksandr Tyshchenko, xen-devel, kernel-janitors
The change from kcalloc() to kvmalloc() means that arg->nr_pages
might now be large enough that the "args->nr_pages << PAGE_SHIFT" can
result in an integer overflow.
Fixes: b3f7931f5c61 ("xen/gntdev: switch from kcalloc() to kvcalloc()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
drivers/xen/grant-table.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 738029de3c67..e1ec725c2819 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -1047,6 +1047,9 @@ int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args)
size_t size;
int i, ret;
+ if (args->nr_pages < 0 || args->nr_pages > (INT_MAX >> PAGE_SHIFT))
+ return -ENOMEM;
+
size = args->nr_pages << PAGE_SHIFT;
if (args->coherent)
args->vaddr = dma_alloc_coherent(args->dev, size,
--
2.35.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] xen/grants: prevent integer overflow in gnttab_dma_alloc_pages()
2022-09-01 15:35 [PATCH] xen/grants: prevent integer overflow in gnttab_dma_alloc_pages() Dan Carpenter
@ 2022-09-02 7:01 ` Juergen Gross
0 siblings, 0 replies; 2+ messages in thread
From: Juergen Gross @ 2022-09-02 7:01 UTC (permalink / raw)
To: Dan Carpenter
Cc: Stefano Stabellini, Oleksandr Tyshchenko, xen-devel, kernel-janitors
[-- Attachment #1.1.1: Type: text/plain, Size: 415 bytes --]
On 01.09.22 17:35, Dan Carpenter wrote:
> The change from kcalloc() to kvmalloc() means that arg->nr_pages
> might now be large enough that the "args->nr_pages << PAGE_SHIFT" can
> result in an integer overflow.
>
> Fixes: b3f7931f5c61 ("xen/gntdev: switch from kcalloc() to kvcalloc()")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Juergen
[-- Attachment #1.1.2: OpenPGP public key --]
[-- Type: application/pgp-keys, Size: 3149 bytes --]
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 495 bytes --]
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2022-09-02 7:01 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-09-01 15:35 [PATCH] xen/grants: prevent integer overflow in gnttab_dma_alloc_pages() Dan Carpenter
2022-09-02 7:01 ` Juergen Gross
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).