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[PATCH v3] staging: rtl8723bs: fix unchecked return value of skb_copy_bits

Minu Jin posted 1 patch 2 weeks, 3 days ago
There is a newer version of this series
drivers/staging/rtl8723bs/core/rtw_xmit.c     | 42 +++++++++++++++----
.../staging/rtl8723bs/include/xmit_osdep.h    |  2 +-
drivers/staging/rtl8723bs/os_dep/xmit_linux.c | 12 ++++--
3 files changed, 42 insertions(+), 14 deletions(-)
[PATCH v3] staging: rtl8723bs: fix unchecked return value of skb_copy_bits
Posted by Minu Jin 2 weeks, 3 days ago 
The function _rtw_pktfile_read() incorrectly updated the file pointer
even when skb_copy_bits() failed.

This patch fixes the issue by:

    1. Propagating the negative error code from skb_copy_bits() if
       it fails, preventing internal pointer updates.

    2. Updating all callers (including set_qos) to check the return value
       and handle errors appropriately.

Signed-off-by: Minu Jin <s9430939@naver.com>
---
Changes in v3:
	- Convert set_qos() from void to int to properly propagate error codes
	  (suggested by Greg KH, Dan Carpenter)

	- Use an intermediate 'ret' variable in set_qos() for cleaner error
	  handling (suggested by Dan Carpenter)

	- Remove 'extern' from function prototype in the header file
	  (suggested by Andy Shevchenko)

	- Apply reverse xmas tree ordering for local variables.
	  (suggested by Andy Shevchenko)

	- Remove unnecessary blank lines in declaration blocks
	  (suggested by Andy Shevchenko, Dan Carpenter)

	- Revert 'len' variable type to uint in _rtw_pktfile_read()
	  (suggested by Dan Carpenter)


 drivers/staging/rtl8723bs/core/rtw_xmit.c     | 42 +++++++++++++++----
 .../staging/rtl8723bs/include/xmit_osdep.h    |  2 +-
 drivers/staging/rtl8723bs/os_dep/xmit_linux.c | 12 ++++--
 3 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_xmit.c b/drivers/staging/rtl8723bs/core/rtw_xmit.c
index 21690857fd62..f24f89ab65ad 100644
--- a/drivers/staging/rtl8723bs/core/rtw_xmit.c
+++ b/drivers/staging/rtl8723bs/core/rtw_xmit.c
@@ -596,23 +596,31 @@ u8 qos_acm(u8 acm_mask, u8 priority)
 	return priority;
 }
 
-static void set_qos(struct pkt_file *ppktfile, struct pkt_attrib *pattrib)
+static int set_qos(struct pkt_file *ppktfile, struct pkt_attrib *pattrib)
 {
 	struct ethhdr etherhdr;
 	struct iphdr ip_hdr;
 	s32 UserPriority = 0;
+	int ret;
 
 	_rtw_open_pktfile(ppktfile->pkt, ppktfile);
-	_rtw_pktfile_read(ppktfile, (unsigned char *)&etherhdr, ETH_HLEN);
+	ret = _rtw_pktfile_read(ppktfile, (unsigned char *)&etherhdr, ETH_HLEN);
+	if (ret < 0)
+		return ret;
 
 	/*  get UserPriority from IP hdr */
 	if (pattrib->ether_type == 0x0800) {
-		_rtw_pktfile_read(ppktfile, (u8 *)&ip_hdr, sizeof(ip_hdr));
+		ret = _rtw_pktfile_read(ppktfile, (u8 *)&ip_hdr, sizeof(ip_hdr));
+		if (ret < 0)
+			return ret;
+
 		UserPriority = ip_hdr.tos >> 5;
 	}
 	pattrib->priority = UserPriority;
 	pattrib->hdrlen = WLAN_HDR_A3_QOS_LEN;
 	pattrib->subtype = WIFI_QOS_DATA_TYPE;
+
+	return 0;
 }
 
 static s32 update_attrib(struct adapter *padapter, struct sk_buff *pkt, struct pkt_attrib *pattrib)
@@ -626,9 +634,12 @@ static s32 update_attrib(struct adapter *padapter, struct sk_buff *pkt, struct p
 	struct mlme_priv *pmlmepriv = &padapter->mlmepriv;
 	struct qos_priv *pqospriv = &pmlmepriv->qospriv;
 	signed int res = _SUCCESS;
+	int ret;
 
 	_rtw_open_pktfile(pkt, &pktfile);
-	_rtw_pktfile_read(&pktfile, (u8 *)&etherhdr, ETH_HLEN);
+	ret = _rtw_pktfile_read(&pktfile, (u8 *)&etherhdr, ETH_HLEN);
+	if (ret < 0)
+		return ret;
 
 	pattrib->ether_type = ntohs(etherhdr.h_proto);
 
@@ -655,7 +666,9 @@ static s32 update_attrib(struct adapter *padapter, struct sk_buff *pkt, struct p
 
 		u8 tmp[24];
 
-		_rtw_pktfile_read(&pktfile, &tmp[0], 24);
+		ret = _rtw_pktfile_read(&pktfile, &tmp[0], 24);
+		if (ret < 0)
+			return ret;
 
 		pattrib->dhcp_pkt = 0;
 		if (pktfile.pkt_len > 282) {/* MINIMUM_DHCP_PACKET_SIZE) { */
@@ -737,11 +750,16 @@ static s32 update_attrib(struct adapter *padapter, struct sk_buff *pkt, struct p
 	pattrib->priority = 0;
 
 	if (check_fwstate(pmlmepriv, WIFI_AP_STATE|WIFI_ADHOC_STATE|WIFI_ADHOC_MASTER_STATE)) {
-		if (pattrib->qos_en)
-			set_qos(&pktfile, pattrib);
+		if (pattrib->qos_en) {
+			ret = set_qos(&pktfile, pattrib);
+			if (ret < 0)
+				return ret;
+		}
 	} else {
 		if (pqospriv->qos_option) {
-			set_qos(&pktfile, pattrib);
+			ret = set_qos(&pktfile, pattrib);
+			if (ret < 0)
+				return ret;
 
 			if (pmlmepriv->acm_mask != 0)
 				pattrib->priority = qos_acm(pmlmepriv->acm_mask, pattrib->priority);
@@ -1039,6 +1057,7 @@ s32 rtw_xmitframe_coalesce(struct adapter *padapter, struct sk_buff *pkt, struct
 
 	s32 bmcst = is_multicast_ether_addr(pattrib->ra);
 	s32 res = _SUCCESS;
+	int ret;
 
 	if (!pxmitframe->buf_addr)
 		return _FAIL;
@@ -1054,7 +1073,9 @@ s32 rtw_xmitframe_coalesce(struct adapter *padapter, struct sk_buff *pkt, struct
 	}
 
 	_rtw_open_pktfile(pkt, &pktfile);
-	_rtw_pktfile_read(&pktfile, NULL, pattrib->pkt_hdrlen);
+	ret = _rtw_pktfile_read(&pktfile, NULL, pattrib->pkt_hdrlen);
+	if (ret < 0)
+		return ret;
 
 	frg_inx = 0;
 	frg_len = pxmitpriv->frag_len - 4;/* 2346-4 = 2342 */
@@ -1096,6 +1117,9 @@ s32 rtw_xmitframe_coalesce(struct adapter *padapter, struct sk_buff *pkt, struct
 			mem_sz = _rtw_pktfile_read(&pktfile, pframe, mpdu_len);
 		}
 
+		if (mem_sz < 0)
+			return mem_sz;
+
 		pframe += mem_sz;
 
 		if ((pattrib->icv_len > 0) && (pattrib->bswenc)) {
diff --git a/drivers/staging/rtl8723bs/include/xmit_osdep.h b/drivers/staging/rtl8723bs/include/xmit_osdep.h
index 8704dced593a..13d86186904c 100644
--- a/drivers/staging/rtl8723bs/include/xmit_osdep.h
+++ b/drivers/staging/rtl8723bs/include/xmit_osdep.h
@@ -35,7 +35,7 @@ void rtw_os_xmit_resource_free(struct adapter *padapter, struct xmit_buf *pxmitb
 
 extern uint rtw_remainder_len(struct pkt_file *pfile);
 extern void _rtw_open_pktfile(struct sk_buff *pkt, struct pkt_file *pfile);
-extern uint _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen);
+int _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen);
 extern signed int rtw_endofpktfile(struct pkt_file *pfile);
 
 extern void rtw_os_pkt_complete(struct adapter *padapter, struct sk_buff *pkt);
diff --git a/drivers/staging/rtl8723bs/os_dep/xmit_linux.c b/drivers/staging/rtl8723bs/os_dep/xmit_linux.c
index 944b9c724b32..553901a66c37 100644
--- a/drivers/staging/rtl8723bs/os_dep/xmit_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/xmit_linux.c
@@ -21,15 +21,19 @@ void _rtw_open_pktfile(struct sk_buff *pktptr, struct pkt_file *pfile)
 	pfile->cur_buffer = pfile->buf_start;
 }
 
-uint _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen)
+int _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen)
 {
-	uint	len = 0;
+	uint len = 0;
+	int ret;
 
 	len =  rtw_remainder_len(pfile);
 	len = (rlen > len) ? len : rlen;
 
-	if (rmem)
-		skb_copy_bits(pfile->pkt, pfile->buf_len - pfile->pkt_len, rmem, len);
+	if (rmem) {
+		ret = skb_copy_bits(pfile->pkt, pfile->buf_len - pfile->pkt_len, rmem, len);
+		if (ret < 0)
+			return ret;
+	}
 
 	pfile->cur_addr += len;
 	pfile->pkt_len -= len;
-- 
2.43.0
Re: [PATCH v3] staging: rtl8723bs: fix unchecked return value of skb_copy_bits
Posted by Andy Shevchenko 2 weeks, 3 days ago 
On Wed, Jan 21, 2026 at 12:50:34AM +0900, Minu Jin wrote:
> The function _rtw_pktfile_read() incorrectly updated the file pointer
> even when skb_copy_bits() failed.
> 
> This patch fixes the issue by:
> 
>     1. Propagating the negative error code from skb_copy_bits() if
>        it fails, preventing internal pointer updates.
> 
>     2. Updating all callers (including set_qos) to check the return value
>        and handle errors appropriately.

...

> -uint _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen)
> +int _rtw_pktfile_read(struct pkt_file *pfile, u8 *rmem, uint rlen)
>  {
> -	uint	len = 0;
> +	uint len = 0;

Use
	unsigned int len;

(Note that the 0 assignment is redundant)


> +	int ret;
>  
>  	len =  rtw_remainder_len(pfile);

^^^ len is assigned here.

-- 
With Best Regards,
Andy Shevchenko
Re: [PATCH v3] staging: rtl8723bs: fix unchecked return value of skb_copy_bits
Posted by Greg KH 2 weeks, 3 days ago 
On Wed, Jan 21, 2026 at 12:50:34AM +0900, Minu Jin wrote:
> The function _rtw_pktfile_read() incorrectly updated the file pointer
> even when skb_copy_bits() failed.
> 
> This patch fixes the issue by:
> 
>     1. Propagating the negative error code from skb_copy_bits() if
>        it fails, preventing internal pointer updates.
> 
>     2. Updating all callers (including set_qos) to check the return value
>        and handle errors appropriately.
> 
> Signed-off-by: Minu Jin <s9430939@naver.com>
> ---
> Changes in v3:
> 	- Convert set_qos() from void to int to properly propagate error codes
> 	  (suggested by Greg KH, Dan Carpenter)
> 
> 	- Use an intermediate 'ret' variable in set_qos() for cleaner error
> 	  handling (suggested by Dan Carpenter)
> 
> 	- Remove 'extern' from function prototype in the header file
> 	  (suggested by Andy Shevchenko)
> 
> 	- Apply reverse xmas tree ordering for local variables.
> 	  (suggested by Andy Shevchenko)
> 
> 	- Remove unnecessary blank lines in declaration blocks
> 	  (suggested by Andy Shevchenko, Dan Carpenter)
> 
> 	- Revert 'len' variable type to uint in _rtw_pktfile_read()
> 	  (suggested by Dan Carpenter)
> 
> 
>  drivers/staging/rtl8723bs/core/rtw_xmit.c     | 42 +++++++++++++++----
>  .../staging/rtl8723bs/include/xmit_osdep.h    |  2 +-
>  drivers/staging/rtl8723bs/os_dep/xmit_linux.c | 12 ++++--
>  3 files changed, 42 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/staging/rtl8723bs/core/rtw_xmit.c b/drivers/staging/rtl8723bs/core/rtw_xmit.c
> index 21690857fd62..f24f89ab65ad 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_xmit.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_xmit.c
> @@ -596,23 +596,31 @@ u8 qos_acm(u8 acm_mask, u8 priority)
>  	return priority;
>  }
>  
> -static void set_qos(struct pkt_file *ppktfile, struct pkt_attrib *pattrib)
> +static int set_qos(struct pkt_file *ppktfile, struct pkt_attrib *pattrib)
>  {
>  	struct ethhdr etherhdr;
>  	struct iphdr ip_hdr;
>  	s32 UserPriority = 0;
> +	int ret;
>  
>  	_rtw_open_pktfile(ppktfile->pkt, ppktfile);
> -	_rtw_pktfile_read(ppktfile, (unsigned char *)&etherhdr, ETH_HLEN);
> +	ret = _rtw_pktfile_read(ppktfile, (unsigned char *)&etherhdr, ETH_HLEN);
> +	if (ret < 0)
> +		return ret;

How can ret ever be less than 0?

Shouldn't you be checking something else here?

Hint, read the function to see what it does...

thanks,

greg k-h

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