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/zlib_inflate/infutil.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 lib/zlib_inflate/infutil.c (limited to 'lib/zlib_inflate/infutil.c') diff --git a/lib/zlib_inflate/infutil.c b/lib/zlib_inflate/infutil.c new file mode 100644 index 000000000..12169aacd --- /dev/null +++ b/lib/zlib_inflate/infutil.c @@ -0,0 +1,49 @@ +#include +#include +#include +#include + +/* Utility function: initialize zlib, unpack binary blob, clean up zlib, + * return len or negative error code. + */ +int zlib_inflate_blob(void *gunzip_buf, unsigned int sz, + const void *buf, unsigned int len) +{ + const u8 *zbuf = buf; + struct z_stream_s *strm; + int rc; + + rc = -ENOMEM; + strm = kmalloc_obj(*strm); + if (strm == NULL) + goto gunzip_nomem1; + strm->workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); + if (strm->workspace == NULL) + goto gunzip_nomem2; + + /* gzip header (1f,8b,08... 10 bytes total + possible asciz filename) + * expected to be stripped from input + */ + strm->next_in = zbuf; + strm->avail_in = len; + strm->next_out = gunzip_buf; + strm->avail_out = sz; + + rc = zlib_inflateInit2(strm, -MAX_WBITS); + if (rc == Z_OK) { + rc = zlib_inflate(strm, Z_FINISH); + /* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */ + if (rc == Z_STREAM_END) + rc = sz - strm->avail_out; + else + rc = -EINVAL; + zlib_inflateEnd(strm); + } else + rc = -EINVAL; + + kfree(strm->workspace); +gunzip_nomem2: + kfree(strm); +gunzip_nomem1: + return rc; /* returns Z_OK (0) if successful */ +} -- cgit v1.3.1