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([2405:201:31:d01f:bb2d:e035:1f86:719f]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2a951c782desm60852705ad.25.2026.02.07.11.29.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Feb 2026 11:29:31 -0800 (PST) From: Soham Kute To: gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Soham Kute , syzbot+03f79366754268a0f20c@syzkaller.appspotmail.com Subject: [PATCH] tty: vt: keyboard: fix general protection fault in k_meta Date: Sun, 8 Feb 2026 00:57:08 +0530 Message-Id: <20260207192708.44188-1-officialsohamkute@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit syzbot reported a general protection fault in k_meta() caused by dereferencing an invalid keyboard pointer when checking META mode. Add a defensive check to ensure the keyboard pointer is valid before calling vc_kbd_mode(). Reported-by: syzbot+03f79366754268a0f20c@syzkaller.appspotmail.com Signed-off-by: Soham Kute --- drivers/tty/vt/keyboard.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c index d65fc60dd..b535d7a42 100644 --- a/drivers/tty/vt/keyboard.c +++ b/drivers/tty/vt/keyboard.c @@ -880,7 +880,7 @@ static void k_meta(struct vc_data *vc, unsigned char value, char up_flag) if (up_flag) return; - if (vc_kbd_mode(kbd, VC_META)) { + if (kbd && vc_kbd_mode(kbd, VC_META)) { put_queue(vc, '\033'); put_queue(vc, value); } else -- 2.34.1