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authorMuhammad Bilal <meatuni001@gmail.com>2026-07-28 17:54:55 +0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-09-01 12:15:16 +0200
commitff917923f4fb9c83717ba135ee47d7e4c1567bb7 (patch)
treec38fd8fcf58e1937b17fdbc6518b6f8b797fc15a /Documentation/admin-guide/lcd-panel-cgram.rst
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staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted
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 <meatuni001@gmail.com> Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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+======================================
+Parallel port LCD/Keypad Panel support
+======================================
+
+Some LCDs allow you to define up to 8 characters, mapped to ASCII
+characters 0 to 7. The escape code to define a new character is
+'\e[LG' followed by one digit from 0 to 7, representing the character
+number, and up to 8 couples of hex digits terminated by a semi-colon
+(';'). Each couple of digits represents a line, with 1-bits for each
+illuminated pixel with LSB on the right. Lines are numbered from the
+top of the character to the bottom. On a 5x7 matrix, only the 5 lower
+bits of the 7 first bytes are used for each character. If the string
+is incomplete, only complete lines will be redefined. Here are some
+examples::
+
+ printf "\e[LG0010101050D1F0C04;" => 0 = [enter]
+ printf "\e[LG1040E1F0000000000;" => 1 = [up]
+ printf "\e[LG2000000001F0E0400;" => 2 = [down]
+ printf "\e[LG3040E1F001F0E0400;" => 3 = [up-down]
+ printf "\e[LG40002060E1E0E0602;" => 4 = [left]
+ printf "\e[LG500080C0E0F0E0C08;" => 5 = [right]
+ printf "\e[LG60016051516141400;" => 6 = "IP"
+
+ printf "\e[LG00103071F1F070301;" => big speaker
+ printf "\e[LG00002061E1E060200;" => small speaker
+
+Willy