From 28a289beaf226b30b1e6e7d7b1a2946fe2d6e852 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Tue, 28 Jul 2026 17:54:56 +0500 Subject: [PATCH] staging: rtl8723bs: fix OOB read in rtw_restruct_wmm_ie() rtw_restruct_wmm_ie() scans in_ie for a WMM IE with: while (i < in_len) { ... if (i + 5 < in_len && in_ie[i] == 0xDD && ...) { ... break; } i += (in_ie[i + 1] + 2); /* to the next IE element */ } When the "i + 5 < in_len" match check fails simply because i is within 5 bytes of the end of the buffer (i.e. no WMM IE was found near the tail of in_ie), execution falls through to "i += (in_ie[i + 1] + 2)", which reads in_ie[i + 1]. If i == in_len - 1 at that point, this is a 1-byte out-of-bounds read of an attacker-influenced IE buffer built from association/scan data. Commit a75281626fc8f ("staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie") added the "i + 5 < in_len" guard to the match condition itself, but did not add an equivalent guard before the fallthrough advance, so the same class of OOB read remained reachable through the non-matching path. Add an explicit bounds check before advancing to the next IE. Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Link: https://patch.msgid.link/20260728125456.32359-4-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtl8723bs/core/rtw_mlme.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme.c b/drivers/staging/rtl8723bs/core/rtw_mlme.c index fc46b33b836a..d18768a51b19 100644 --- a/drivers/staging/rtl8723bs/core/rtw_mlme.c +++ b/drivers/staging/rtl8723bs/core/rtw_mlme.c @@ -1975,6 +1975,9 @@ int rtw_restruct_wmm_ie(struct adapter *adapter, u8 *in_ie, u8 *out_ie, uint in_ break; } + if (i + 1 >= in_len) + break; + i += (in_ie[i + 1] + 2); /* to the next IE element */ }