2018-01-08 23:51:50

by Ryan Hsu

Subject: [PATCH] ath10k: add sanity check to ie_len before parsing fw/board ie

From: Ryan Hsu <[email protected]>

Validate ie_len after the alignment padding before access the buffer
to avoid potential overflow.

Signed-off-by: Ryan Hsu <[email protected]>
---
drivers/net/wireless/ath/ath10k/core.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
index 51444d3..64713d1 100644
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -1276,7 +1276,10 @@ static int ath10k_core_fetch_board_data_api_n(struct ath10k *ar,
len -= sizeof(*hdr);
data = hdr->data;

- if (len < ALIGN(ie_len, 4)) {
+ /* jump over the padding */
+ ie_len = ALIGN(ie_len, 4);
+
+ if (len < ie_len) {
ath10k_err(ar, "invalid length for board ie_id %d ie_len %zu len %zu\n",
ie_id, ie_len, len);
ret = -EINVAL;
@@ -1315,8 +1318,6 @@ static int ath10k_core_fetch_board_data_api_n(struct ath10k *ar,
goto out;
}

- /* jump over the padding */
- ie_len = ALIGN(ie_len, 4);

len -= ie_len;
data += ie_len;
@@ -1448,6 +1449,9 @@ int ath10k_core_fetch_firmware_api_n(struct ath10k *ar, const char *name,
len -= sizeof(*hdr);
data += sizeof(*hdr);

+ /* jump over the padding */
+ ie_len = ALIGN(ie_len, 4);
+
if (len < ie_len) {
ath10k_err(ar, "invalid length for FW IE %d (%zu < %zu)\n",
ie_id, len, ie_len);
@@ -1553,9 +1557,6 @@ int ath10k_core_fetch_firmware_api_n(struct ath10k *ar, const char *name,
break;
}

- /* jump over the padding */
- ie_len = ALIGN(ie_len, 4);
-
len -= ie_len;
data += ie_len;
}
--
1.9.1

2018-01-16 14:31:52

by Kalle Valo

Subject: Re: ath10k: add sanity check to ie_len before parsing fw/board ie

[email protected] wrote:

> Validate ie_len after the alignment padding before access the buffer
> to avoid potential overflow.
>
> Signed-off-by: Ryan Hsu <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

9ed4f9162873 ath10k: add sanity check to ie_len before parsing fw/board ie

--
https://patchwork.kernel.org/patch/10150769/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches