From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E07A4303A16; Tue, 30 Sep 2025 14:52:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759243978; cv=none; b=d0kVjQ8YhtX9bqmxY+7e0krw/G4b4TZwcXKk0ScLo9mggiSKfM0gpv4wSdUlx2ylNV96L7MLaahBqo+jzP2MTxRIbItBnuRSkWgqCyu6XX9X/gRvPTA5OlCn2bW3PJwA4hhPBORmfQLISazPwbd8DFwD34TzGY0rtgQdeYpu15k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759243978; c=relaxed/simple; bh=/iETv8s4/dysVgthExeGhnEx4d3T/hkkV68XAAVrQLY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=D8y2+xRyC7HrzwZIMA+pfR/EXrCT9JpgSI8V0Tdcrb5s+QAZZIDbNezcJ9NCD6ofvDgxxA1T9BepXkfIAw+q2FvGtqVmJcY/6CoT3SrBC8wx8O16Pz1NbkBrl9wM7qI6VT5zapGIz1EEBy37IC9TOEre2v8iR5BjIhYfQ4velqE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=t3C1frmC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="t3C1frmC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1F6C8C4CEF0; Tue, 30 Sep 2025 14:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1759243977; bh=/iETv8s4/dysVgthExeGhnEx4d3T/hkkV68XAAVrQLY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t3C1frmCxfuSuIFXtgzuXxdS3TPbiwOEQ6NrS3HEs6dOFQ2yT7rEvO9gxtHjaeBFw MiUUw9qBCm6vXI5RkzjHy8DSiqMF/uniHG+8BZ2AeyCsncrMY+I5bA1KtIrg8mFqEr U81XEOGE/cEueKk6S+BYJqf+7Jb6VL2katBcLLHw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thomas Zimmermann , Jani Nikula , Samasth Norway Ananda , George Kennedy , Simona Vetter , Helge Deller , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Sam Ravnborg , Qianqiang Liu , Shixiong Ou , Kees Cook , Zsolt Kajtar , Lucas De Marchi Subject: [PATCH 5.4 74/81] fbcon: Fix OOB access in font allocation Date: Tue, 30 Sep 2025 16:47:16 +0200 Message-ID: <20250930143822.802613888@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250930143819.654157320@linuxfoundation.org> References: <20250930143819.654157320@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Zimmermann commit 9b2f5ef00e852f8e8902a4d4f73aeedc60220c12 upstream. Commit 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font") introduced an out-of-bounds access by storing data and allocation sizes in the same variable. Restore the old size calculation and use the new variable 'alloc_size' for the allocation. Signed-off-by: Thomas Zimmermann Fixes: 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font") Reported-by: Jani Nikula Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15020 Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6201 Cc: Samasth Norway Ananda Cc: Thomas Zimmermann Cc: George Kennedy Cc: Greg Kroah-Hartman Cc: Simona Vetter Cc: Helge Deller Cc: "Ville Syrjälä" Cc: Sam Ravnborg Cc: Qianqiang Liu Cc: Shixiong Ou Cc: Kees Cook Cc: # v5.9+ Cc: Zsolt Kajtar Reviewed-by: Lucas De Marchi Reviewed-by: Qianqiang Liu Link: https://lore.kernel.org/r/20250922134619.257684-1-tzimmermann@suse.de Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/core/fbcon.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -2482,7 +2482,7 @@ static int fbcon_set_font(struct vc_data unsigned charcount = font->charcount; int w = font->width; int h = font->height; - int size; + int size, alloc_size; int i, csum; u8 *new_data, *data = font->data; int pitch = PITCH(font->width); @@ -2515,10 +2515,10 @@ static int fbcon_set_font(struct vc_data return -EINVAL; /* Check for overflow in allocation size calculation */ - if (check_add_overflow(FONT_EXTRA_WORDS * sizeof(int), size, &size)) + if (check_add_overflow(FONT_EXTRA_WORDS * sizeof(int), size, &alloc_size)) return -EINVAL; - new_data = kmalloc(size, GFP_USER); + new_data = kmalloc(alloc_size, GFP_USER); if (!new_data) return -ENOMEM;