From: Nicolas Boichat <[email protected]>
When the FW bundles multiple packets, pkt->act_len may be incorrect
as it refers to the first packet only (however, the FW will only
bundle packets that fit into the same pkt->alloc_len).
Before this patch, the skb length would be set (incorrectly) to
pkt->act_len in ath10k_sdio_mbox_rx_packet, and then later manually
adjusted in ath10k_sdio_mbox_rx_process_packet.
The first problem is that ath10k_sdio_mbox_rx_process_packet does not
use proper skb_put commands to adjust the length (it directly changes
skb->len), so we end up with a mismatch between skb->head + skb->tail
and skb->data + skb->len. This is quite serious, and causes corruptions
in the TCP stack, as the stack tries to coalesce packets, and relies
on skb->tail being correct (that is, skb_tail_pointer must point to
the first byte_after_ the data).
Instead of re-adjusting the size in ath10k_sdio_mbox_rx_process_packet,
this moves the code to ath10k_sdio_mbox_rx_packet, and also add a
bounds check, as skb_put would crash the kernel if not enough space is
available.
Tested with QCA6174 SDIO with firmware
WLAN.RMH.4.4.1-00007-QCARMSWP-1.
Fixes: 8530b4e7b22bc3b ("ath10k: sdio: set skb len for all rx packets")
Signed-off-by: Nicolas Boichat <[email protected]>
Signed-off-by: Wen Gong <[email protected]>
---
v2: no this patch
v3: new added
v4: change commit log
v5: no change
drivers/net/wireless/ath/ath10k/sdio.c | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)
diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c
index 8ed4fbd..1127e44 100644
--- a/drivers/net/wireless/ath/ath10k/sdio.c
+++ b/drivers/net/wireless/ath/ath10k/sdio.c
@@ -381,16 +381,11 @@ static int ath10k_sdio_mbox_rx_process_packet(struct ath10k *ar,
struct ath10k_htc_hdr *htc_hdr = (struct ath10k_htc_hdr *)skb->data;
bool trailer_present = htc_hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT;
enum ath10k_htc_ep_id eid;
- u16 payload_len;
u8 *trailer;
int ret;
- payload_len = le16_to_cpu(htc_hdr->len);
- skb->len = payload_len + sizeof(struct ath10k_htc_hdr);
-
if (trailer_present) {
- trailer = skb->data + sizeof(*htc_hdr) +
- payload_len - htc_hdr->trailer_len;
+ trailer = skb->data + skb->len - htc_hdr->trailer_len;
eid = pipe_id_to_eid(htc_hdr->eid);
@@ -632,13 +627,29 @@ static int ath10k_sdio_mbox_rx_packet(struct ath10k *ar,
{
struct ath10k_sdio *ar_sdio = ath10k_sdio_priv(ar);
struct sk_buff *skb = pkt->skb;
+ struct ath10k_htc_hdr *htc_hdr;
int ret;
ret = ath10k_sdio_readsb(ar, ar_sdio->mbox_info.htc_addr,
skb->data, pkt->alloc_len);
+
+ if (!ret) {
+ /* Update actual length. The original length may be incorrect,
+ * as the FW will bundle multiple packets as long as their sizes
+ * fit within the same aligned length (pkt->alloc_len).
+ */
+ htc_hdr = (struct ath10k_htc_hdr *)skb->data;
+ pkt->act_len = le16_to_cpu(htc_hdr->len) + sizeof(*htc_hdr);
+ if (pkt->act_len <= pkt->alloc_len) {
+ skb_put(skb, pkt->act_len);
+ } else {
+ ath10k_warn(ar, "rx packet too large (%zu > %zu)\n",
+ pkt->act_len, pkt->alloc_len);
+ ret = -EMSGSIZE;
+ }
+ }
+
pkt->status = ret;
- if (!ret)
- skb_put(skb, pkt->act_len);
return ret;
}
--
1.9.1
Wen Gong <[email protected]> writes:
> From: Nicolas Boichat <[email protected]>
>
> When the FW bundles multiple packets, pkt->act_len may be incorrect
> as it refers to the first packet only (however, the FW will only
> bundle packets that fit into the same pkt->alloc_len).
>
> Before this patch, the skb length would be set (incorrectly) to
> pkt->act_len in ath10k_sdio_mbox_rx_packet, and then later manually
> adjusted in ath10k_sdio_mbox_rx_process_packet.
>
> The first problem is that ath10k_sdio_mbox_rx_process_packet does not
> use proper skb_put commands to adjust the length (it directly changes
> skb->len), so we end up with a mismatch between skb->head + skb->tail
> and skb->data + skb->len. This is quite serious, and causes corruptions
> in the TCP stack, as the stack tries to coalesce packets, and relies
> on skb->tail being correct (that is, skb_tail_pointer must point to
> the first byte_after_ the data).
>
> Instead of re-adjusting the size in ath10k_sdio_mbox_rx_process_packet,
> this moves the code to ath10k_sdio_mbox_rx_packet, and also add a
> bounds check, as skb_put would crash the kernel if not enough space is
> available.
>
> Tested with QCA6174 SDIO with firmware
> WLAN.RMH.4.4.1-00007-QCARMSWP-1.
>
> Fixes: 8530b4e7b22bc3b ("ath10k: sdio: set skb len for all rx packets")
> Signed-off-by: Nicolas Boichat <[email protected]>
> Signed-off-by: Wen Gong <[email protected]>
[...]
> @@ -632,13 +627,29 @@ static int ath10k_sdio_mbox_rx_packet(struct ath10k *ar,
> {
> struct ath10k_sdio *ar_sdio = ath10k_sdio_priv(ar);
> struct sk_buff *skb = pkt->skb;
> + struct ath10k_htc_hdr *htc_hdr;
> int ret;
>
> ret = ath10k_sdio_readsb(ar, ar_sdio->mbox_info.htc_addr,
> skb->data, pkt->alloc_len);
> +
> + if (!ret) {
> + /* Update actual length. The original length may be incorrect,
> + * as the FW will bundle multiple packets as long as their sizes
> + * fit within the same aligned length (pkt->alloc_len).
> + */
> + htc_hdr = (struct ath10k_htc_hdr *)skb->data;
> + pkt->act_len = le16_to_cpu(htc_hdr->len) + sizeof(*htc_hdr);
> + if (pkt->act_len <= pkt->alloc_len) {
> + skb_put(skb, pkt->act_len);
> + } else {
> + ath10k_warn(ar, "rx packet too large (%zu > %zu)\n",
> + pkt->act_len, pkt->alloc_len);
> + ret = -EMSGSIZE;
> + }
> + }
> +
> pkt->status = ret;
> - if (!ret)
> - skb_put(skb, pkt->act_len);
>
> return ret;
> }
I simplified the error handling in this function to follow the ath10k
style, please check carefully that I didn't create any bugs:
https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/commit/?h=pending&id=6e4d2cc5
--
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On Thu, Sep 12, 2019 at 9:46 PM Kalle Valo <[email protected]> wrote:
>
> Wen Gong <[email protected]> writes:
>
> > From: Nicolas Boichat <[email protected]>
> [...]
>
> I simplified the error handling in this function to follow the ath10k
> style, please check carefully that I didn't create any bugs:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/commit/?h=pending&id=6e4d2cc5
Thanks, that looks right.
> --
> https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
Wen Gong <[email protected]> wrote:
> When the FW bundles multiple packets, pkt->act_len may be incorrect
> as it refers to the first packet only (however, the FW will only
> bundle packets that fit into the same pkt->alloc_len).
>
> Before this patch, the skb length would be set (incorrectly) to
> pkt->act_len in ath10k_sdio_mbox_rx_packet, and then later manually
> adjusted in ath10k_sdio_mbox_rx_process_packet.
>
> The first problem is that ath10k_sdio_mbox_rx_process_packet does not
> use proper skb_put commands to adjust the length (it directly changes
> skb->len), so we end up with a mismatch between skb->head + skb->tail
> and skb->data + skb->len. This is quite serious, and causes corruptions
> in the TCP stack, as the stack tries to coalesce packets, and relies
> on skb->tail being correct (that is, skb_tail_pointer must point to
> the first byte_after_ the data).
>
> Instead of re-adjusting the size in ath10k_sdio_mbox_rx_process_packet,
> this moves the code to ath10k_sdio_mbox_rx_packet, and also add a
> bounds check, as skb_put would crash the kernel if not enough space is
> available.
>
> Tested with QCA6174 SDIO with firmware
> WLAN.RMH.4.4.1-00007-QCARMSWP-1.
>
> Fixes: 8530b4e7b22bc3b ("ath10k: sdio: set skb len for all rx packets")
> Signed-off-by: Nicolas Boichat <[email protected]>
> Signed-off-by: Wen Gong <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>
Patch applied to ath-next branch of ath.git, thanks.
b7139960832e ath10k: adjust skb length in ath10k_sdio_mbox_rx_packet
--
https://patchwork.kernel.org/patch/11132657/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches