From ff917923f4fb9c83717ba135ee47d7e4c1567bb7 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Tue, 28 Jul 2026 17:54:55 +0500 Subject: staging: rtl8723bs: fix OOB read in rtw_action_frame_parse() rtw_action_frame_parse() takes a frame_len parameter but never actually checks it before indexing into the frame body: const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr); ... c = frame_body[0]; ... a = frame_body[1]; frame_body already points 24 bytes (sizeof(struct ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and frame_body[1] requires frame_len >= 26. A management action frame shorter than that (e.g. exactly 24 bytes, the minimum a malicious peer can send) causes a 1-2 byte out-of-bounds read. This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass attacker/user-influenced frame buffers and lengths straight through. Add the missing length check before frame_body is dereferenced. Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman --- tools/include/vdso/bits.h | 10 ++++++++++ tools/include/vdso/const.h | 10 ++++++++++ tools/include/vdso/unaligned.h | 44 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 64 insertions(+) create mode 100644 tools/include/vdso/bits.h create mode 100644 tools/include/vdso/const.h create mode 100644 tools/include/vdso/unaligned.h (limited to 'tools/include/vdso') diff --git a/tools/include/vdso/bits.h b/tools/include/vdso/bits.h new file mode 100644 index 000000000..388b21208 --- /dev/null +++ b/tools/include/vdso/bits.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_BITS_H +#define __VDSO_BITS_H + +#include + +#define BIT(nr) (UL(1) << (nr)) +#define BIT_ULL(nr) (ULL(1) << (nr)) + +#endif /* __VDSO_BITS_H */ diff --git a/tools/include/vdso/const.h b/tools/include/vdso/const.h new file mode 100644 index 000000000..94b385ad4 --- /dev/null +++ b/tools/include/vdso/const.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_CONST_H +#define __VDSO_CONST_H + +#include + +#define UL(x) (_UL(x)) +#define ULL(x) (_ULL(x)) + +#endif /* __VDSO_CONST_H */ diff --git a/tools/include/vdso/unaligned.h b/tools/include/vdso/unaligned.h new file mode 100644 index 000000000..9076483c9 --- /dev/null +++ b/tools/include/vdso/unaligned.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_UNALIGNED_H +#define __VDSO_UNALIGNED_H + +#include + +/** + * __get_unaligned_t - read an unaligned value from memory. + * @type: the type to load from the pointer. + * @ptr: the pointer to load from. + * + * Use memcpy to affect an unaligned type sized load avoiding undefined behavior + * from approaches like type punning that require -fno-strict-aliasing in order + * to be correct. As type may be const, use __unqual_scalar_typeof to map to a + * non-const type - you can't memcpy into a const type. The + * __get_unaligned_ctrl_type gives __unqual_scalar_typeof its required + * expression rather than type, a pointer is used to avoid warnings about mixing + * the use of 0 and NULL. The void* cast silences ubsan warnings. + */ +#define __get_unaligned_t(type, ptr) ({ \ + type *__get_unaligned_ctrl_type __always_unused = NULL; \ + __unqual_scalar_typeof(*__get_unaligned_ctrl_type) __get_unaligned_val; \ + __builtin_memcpy(&__get_unaligned_val, (void *)(ptr), \ + sizeof(__get_unaligned_val)); \ + __get_unaligned_val; \ +}) + +/** + * __put_unaligned_t - write an unaligned value to memory. + * @type: the type of the value to store. + * @val: the value to store. + * @ptr: the pointer to store to. + * + * Use memcpy to affect an unaligned type sized store avoiding undefined + * behavior from approaches like type punning that require -fno-strict-aliasing + * in order to be correct. The void* cast silences ubsan warnings. + */ +#define __put_unaligned_t(type, val, ptr) do { \ + type __put_unaligned_val = (val); \ + __builtin_memcpy((void *)(ptr), &__put_unaligned_val, \ + sizeof(__put_unaligned_val)); \ +} while (0) + +#endif /* __VDSO_UNALIGNED_H */ -- cgit v1.3.1