From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: xen-devel@lists.xensource.com, Ian.Campbell@citrix.com,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] xen-gntdev: prevent using UNMAP_NOTIFY_CLEAR_BYTE on read-only mappings
Date: Wed, 09 Feb 2011 14:22:45 -0800 [thread overview]
Message-ID: <4D5313B5.2030200@goop.org> (raw)
In-Reply-To: <4D52FA23.5060905@tycho.nsa.gov>
On 02/09/2011 12:33 PM, Daniel De Graaf wrote:
> Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
>
> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
> index 4687cd5..00e4644 100644
> --- a/drivers/xen/gntdev.c
> +++ b/drivers/xen/gntdev.c
> @@ -291,7 +291,7 @@ static int __unmap_grant_pages(struct grant_map *map, int offset, int pages)
> if (pgno >= offset && pgno < offset + pages && use_ptemod) {
> void __user *tmp;
> tmp = map->vma->vm_start + map->notify.addr;
> - copy_to_user(tmp, &err, 1);
> + WARN_ON(copy_to_user(tmp, &err, 1));
Please don't put side-effecty predicates in WARN_ON/BUG_ON.
There's no useful report we can return?
J
> map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE;
> } else if (pgno >= offset && pgno < offset + pages) {
> uint8_t *tmp = kmap(map->pages[pgno]);
> @@ -596,6 +596,12 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
> goto unlock_out;
>
> found:
> + if ((op.action & UNMAP_NOTIFY_CLEAR_BYTE) &&
> + (op.flags & GNTMAP_readonly)) {
> + rc = -EINVAL;
> + goto unlock_out;
> + }
> +
> map->notify.flags = op.action;
> map->notify.addr = op.index - (map->index << PAGE_SHIFT);
> map->notify.event = op.event_channel_port;
>
next prev parent reply other threads:[~2011-02-09 22:22 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-03 17:18 [PATCH v6] Userspace grant communication Daniel De Graaf
2011-02-03 17:18 ` [PATCH 1/6] xen-gntdev: Change page limit to be global instead of per-open Daniel De Graaf
2011-02-03 17:19 ` [PATCH 2/6] xen-gntdev: Use find_vma rather than iterating our vma list manually Daniel De Graaf
2011-02-03 17:19 ` [PATCH 3/6] xen-gntdev: Add reference counting to maps Daniel De Graaf
2011-02-03 17:19 ` [PATCH 4/6] xen-gntdev: Support mapping in HVM domains Daniel De Graaf
2011-02-14 15:51 ` Konrad Rzeszutek Wilk
2011-02-14 17:43 ` Daniel De Graaf
2011-02-14 18:52 ` Konrad Rzeszutek Wilk
2011-02-03 17:19 ` [PATCH 5/6] xen-gntalloc: Userspace grant allocation driver Daniel De Graaf
2011-02-08 22:48 ` Konrad Rzeszutek Wilk
2011-02-09 18:52 ` Daniel De Graaf
2011-02-03 17:19 ` [PATCH 6/6] xen/gntalloc, gntdev: Add unmap notify ioctl Daniel De Graaf
2011-02-14 15:37 ` Konrad Rzeszutek Wilk
2011-02-14 18:07 ` Daniel De Graaf
2011-02-03 19:16 ` [PATCH] xen-gntdev: Fix memory leak when mmap fails Daniel De Graaf
2011-02-07 23:14 ` [PATCH v6] Userspace grant communication Konrad Rzeszutek Wilk
2011-02-08 14:14 ` [PATCH] xen-gntdev: Fix unmap notify on PV domains Daniel De Graaf
2011-02-08 22:58 ` Konrad Rzeszutek Wilk
2011-02-09 20:33 ` [PATCH] xen-gntdev: prevent using UNMAP_NOTIFY_CLEAR_BYTE on read-only mappings Daniel De Graaf
2011-02-09 21:09 ` [PATCH v2] " Daniel De Graaf
2011-02-09 22:22 ` Jeremy Fitzhardinge [this message]
2011-02-09 23:11 ` [PATCH] " Daniel De Graaf
2011-02-09 23:15 ` [PATCH v3] " Daniel De Graaf
2011-02-08 21:49 ` [PATCH v6] Userspace grant communication Konrad Rzeszutek Wilk
2011-02-09 20:11 ` [PATCH] xen-gntdev: Use map->vma for checking map validity Daniel De Graaf
2011-02-09 20:12 ` [PATCH] xen-gntdev: Avoid unmapping ranges twice Daniel De Graaf
2011-02-09 21:11 ` [PATCH] xen-gntdev: Avoid double-mapping memory Daniel De Graaf
2011-02-14 16:14 ` [PATCH v6] Userspace grant communication Konrad Rzeszutek Wilk
2011-02-14 16:38 ` Konrad Rzeszutek Wilk
2011-02-14 17:56 ` Daniel De Graaf
2011-02-14 19:21 ` Konrad Rzeszutek Wilk
2011-02-14 20:55 ` Daniel De Graaf
2011-02-14 17:55 ` Daniel De Graaf
2011-02-14 19:04 ` Konrad Rzeszutek Wilk
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