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 --- lib/fault-inject-usercopy.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 lib/fault-inject-usercopy.c (limited to 'lib/fault-inject-usercopy.c') diff --git a/lib/fault-inject-usercopy.c b/lib/fault-inject-usercopy.c new file mode 100644 index 000000000..75403ec50 --- /dev/null +++ b/lib/fault-inject-usercopy.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include + +static struct { + struct fault_attr attr; +} fail_usercopy = { + .attr = FAULT_ATTR_INITIALIZER, +}; + +static int __init setup_fail_usercopy(char *str) +{ + return setup_fault_attr(&fail_usercopy.attr, str); +} +__setup("fail_usercopy=", setup_fail_usercopy); + +#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS + +static int __init fail_usercopy_debugfs(void) +{ + struct dentry *dir; + + dir = fault_create_debugfs_attr("fail_usercopy", NULL, + &fail_usercopy.attr); + + return PTR_ERR_OR_ZERO(dir); +} + +late_initcall(fail_usercopy_debugfs); + +#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ + +bool should_fail_usercopy(void) +{ + return should_fail(&fail_usercopy.attr, 1); +} +EXPORT_SYMBOL_GPL(should_fail_usercopy); -- cgit v1.3.1