[PATCH v2 01/26] staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie

[PATCH v2 01/26] staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie

[lukagejak5]

From: Luka Gejak <luka.gejak@linux.dev>

The current code checks 'i + 5 < in_len' at the end of the if statement.
However, it accesses 'in_ie[i + 5]' before that check, which can lead
to an out-of-bounds read. Move the length check to the beginning of the
conditional to ensure the index is within bounds before accessing the
array.

Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable@vger.kernel.org
Signed-off-by: Luka Gejak <luka.gejak@linux.dev>
---
 drivers/staging/rtl8723bs/core/rtw_mlme.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme.c b/drivers/staging/rtl8723bs/core/rtw_mlme.c
index 8e1e1c97f0c4..0b82b1f2f1ec 100644
--- a/drivers/staging/rtl8723bs/core/rtw_mlme.c
+++ b/drivers/staging/rtl8723bs/core/rtw_mlme.c
@@ -2000,7 +2000,10 @@ int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_
 	while (i < in_len) {
 		ielength = initial_out_len;
 
-		if (in_ie[i] == 0xDD && in_ie[i + 2] == 0x00 && in_ie[i + 3] == 0x50  && in_ie[i + 4] == 0xF2 && in_ie[i + 5] == 0x02 && i + 5 < in_len) { /* WMM element ID and OUI */
+		if (i + 5 < in_len &&
+		    in_ie[i] == 0xDD && in_ie[i + 2] == 0x00 &&
+		    in_ie[i + 3] == 0x50 && in_ie[i + 4] == 0xF2 &&
+		    in_ie[i + 5] == 0x02) {
 			for (j = i; j < i + 9; j++) {
 				out_ie[ielength] = in_ie[j];
 				ielength++;
-- 
2.52.0

Re: [PATCH v2 01/26] staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie

[Greg Kroah-Hartman]

On Fri, Feb 06, 2026 at 08:54:14AM +0100, lukagejak5@gmail.com wrote:
> From: Luka Gejak <luka.gejak@linux.dev>
> 
> The current code checks 'i + 5 < in_len' at the end of the if statement.
> However, it accesses 'in_ie[i + 5]' before that check, which can lead
> to an out-of-bounds read. Move the length check to the beginning of the
> conditional to ensure the index is within bounds before accessing the
> array.
> 
> Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Luka Gejak <luka.gejak@linux.dev>
> ---
>  drivers/staging/rtl8723bs/core/rtw_mlme.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme.c b/drivers/staging/rtl8723bs/core/rtw_mlme.c
> index 8e1e1c97f0c4..0b82b1f2f1ec 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_mlme.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_mlme.c
> @@ -2000,7 +2000,10 @@ int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_
>  	while (i < in_len) {
>  		ielength = initial_out_len;
>  
> -		if (in_ie[i] == 0xDD && in_ie[i + 2] == 0x00 && in_ie[i + 3] == 0x50  && in_ie[i + 4] == 0xF2 && in_ie[i + 5] == 0x02 && i + 5 < in_len) { /* WMM element ID and OUI */
> +		if (i + 5 < in_len &&
> +		    in_ie[i] == 0xDD && in_ie[i + 2] == 0x00 &&
> +		    in_ie[i + 3] == 0x50 && in_ie[i + 4] == 0xF2 &&
> +		    in_ie[i + 5] == 0x02) {
>  			for (j = i; j < i + 9; j++) {
>  				out_ie[ielength] = in_ie[j];
>  				ielength++;
> -- 
> 2.52.0
> 
> 

You still have an extra space in the subject line :(

And I think I took some of these changes already, can you rebase the
rest of these against my tree and resend them?

thanks,

greg k-h