From: Felix Fietkau <nbd@nbd.name>
To: linux-wireless@vger.kernel.org
Cc: kvalo@codeaurora.org, stable@vger.kernel.org
Subject: [PATCH 5.6] mt76: fix array overflow on receiving too many fragments for a packet
Date: Thu, 20 Feb 2020 12:41:39 +0100 [thread overview]
Message-ID: <20200220114139.46508-1-nbd@nbd.name> (raw)
If the hardware receives an oversized packet with too many rx fragments,
skb_shinfo(skb)->frags can overflow and corrupt memory of adjacent pages.
This becomes especially visible if it corrupts the freelist pointer of
a slab page.
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
drivers/net/wireless/mediatek/mt76/dma.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
index 6173c80189ba..1847f55e199b 100644
--- a/drivers/net/wireless/mediatek/mt76/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/dma.c
@@ -447,10 +447,13 @@ mt76_add_fragment(struct mt76_dev *dev, struct mt76_queue *q, void *data,
struct page *page = virt_to_head_page(data);
int offset = data - page_address(page);
struct sk_buff *skb = q->rx_head;
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
- offset += q->buf_offset;
- skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, len,
- q->buf_size);
+ if (shinfo->nr_frags < ARRAY_SIZE(shinfo->frags)) {
+ offset += q->buf_offset;
+ skb_add_rx_frag(skb, shinfo->nr_frags, page, offset, len,
+ q->buf_size);
+ }
if (more)
return;
--
2.24.0
next reply other threads:[~2020-02-20 11:41 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-20 11:41 Felix Fietkau [this message]
2020-02-22 14:13 ` [PATCH 5.6] mt76: fix array overflow on receiving too many fragments for a packet Sasha Levin
2020-03-03 15:30 ` Kalle Valo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200220114139.46508-1-nbd@nbd.name \
--to=nbd@nbd.name \
--cc=kvalo@codeaurora.org \
--cc=linux-wireless@vger.kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).