[PATCH] NFC: fix attrs checks in netlink interface

[PATCH] NFC: fix attrs checks in netlink interface

[Andrey Konovalov]

nfc_genl_deactivate_target() relies on the NFC_ATTR_TARGET_INDEX
attribute being present, but doesn't check whether it is actually
provided by the user. Same goes for nfc_genl_fw_download() and
NFC_ATTR_FIRMWARE_NAME.

This patch adds appropriate checks.

Found with syzkaller.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 net/nfc/netlink.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index f018eafc2a0d..58adfb0c90f6 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -936,7 +936,8 @@ static int nfc_genl_deactivate_target(struct sk_buff *skb,
 	u32 device_idx, target_idx;
 	int rc;
 
-	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+	    !info->attrs[NFC_ATTR_TARGET_INDEX])
 		return -EINVAL;
 
 	device_idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
@@ -1245,7 +1246,8 @@ static int nfc_genl_fw_download(struct sk_buff *skb, struct genl_info *info)
 	u32 idx;
 	char firmware_name[NFC_FIRMWARE_NAME_MAXSIZE + 1];
 
-	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+	    !info->attrs[NFC_ATTR_FIRMWARE_NAME])
 		return -EINVAL;
 
 	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
-- 
2.17.0.484.g0c8726318c-goog

Re: [PATCH] NFC: fix attrs checks in netlink interface

[Samuel Ortiz]

Hi Andrey,

On Thu, Apr 12, 2018 at 06:56:56PM +0200, Andrey Konovalov wrote:
> nfc_genl_deactivate_target() relies on the NFC_ATTR_TARGET_INDEX
> attribute being present, but doesn't check whether it is actually
> provided by the user. Same goes for nfc_genl_fw_download() and
> NFC_ATTR_FIRMWARE_NAME.
> 
> This patch adds appropriate checks.
> 
> Found with syzkaller.
> 
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> ---
>  net/nfc/netlink.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
Thanks, applied to nfc-next.

Cheers,
Samuel.

Re: [PATCH] NFC: fix attrs checks in netlink interface

[Andrey Konovalov]

On Mon, Jun 4, 2018 at 6:29 AM Samuel Ortiz <sameo@linux.intel.com> wrote:
>
> Hi Andrey,
>
> On Thu, Apr 12, 2018 at 06:56:56PM +0200, Andrey Konovalov wrote:
> > nfc_genl_deactivate_target() relies on the NFC_ATTR_TARGET_INDEX
> > attribute being present, but doesn't check whether it is actually
> > provided by the user. Same goes for nfc_genl_fw_download() and
> > NFC_ATTR_FIRMWARE_NAME.
> >
> > This patch adds appropriate checks.
> >
> > Found with syzkaller.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > ---
> >  net/nfc/netlink.c | 6 ++++--
> >  1 file changed, 4 insertions(+), 2 deletions(-)
> Thanks, applied to nfc-next.

Hi Samuel,

It's been 6 months and this fix is still not in mainline. Did it get lost?

Thanks!

>
> Cheers,
> Samuel.

Re: [PATCH] NFC: fix attrs checks in netlink interface

[Andrey Konovalov]

From: Andrey Konovalov <andreyknvl@google.com>
Date: Wed, Jan 2, 2019 at 4:30 PM
To: Samuel Ortiz
Cc: David S . Miller, <linux-wireless@vger.kernel.org>, netdev, LKML,
Dmitry Vyukov, Kostya Serebryany

> On Mon, Jun 4, 2018 at 6:29 AM Samuel Ortiz <sameo@linux.intel.com> wrote:
> >
> > Hi Andrey,
> >
> > On Thu, Apr 12, 2018 at 06:56:56PM +0200, Andrey Konovalov wrote:
> > > nfc_genl_deactivate_target() relies on the NFC_ATTR_TARGET_INDEX
> > > attribute being present, but doesn't check whether it is actually
> > > provided by the user. Same goes for nfc_genl_fw_download() and
> > > NFC_ATTR_FIRMWARE_NAME.
> > >
> > > This patch adds appropriate checks.
> > >
> > > Found with syzkaller.
> > >
> > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > > ---
> > >  net/nfc/netlink.c | 6 ++++--
> > >  1 file changed, 4 insertions(+), 2 deletions(-)
> > Thanks, applied to nfc-next.
>
> Hi Samuel,
>
> It's been 6 months and this fix is still not in mainline. Did it get lost?

More than a year passed since I've sent this patch, it's still sitting
in the nfc-next tree which hasn't been updated since June last year.
Did NFC stopped being maintained?

>
> Thanks!
>
> >
> > Cheers,
> > Samuel.