From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpo75.interia.pl (smtpo75.interia.pl [217.74.67.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 32ACE3624BC for ; Mon, 14 Sep 2026 06:40:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.74.67.75 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789368061; cv=none; b=AOGAqZ3kY/UWc6sezFpbn2bH7L1OcFL1dvefQz7dZWMPDMPxBew1ARdlHNUKMaOvXYTZ/xDHnmxzrKR0JeJHyPA0pkiMclBgic39yccKRK2qkyn6phKS8BDHxuMUIeP7KmlRhYxksxSYgoM9KE8rIT28pQyvKKWqXx9eaMEwJbk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789368061; c=relaxed/simple; bh=QO7dVWJRLZKDWl34KsraszC5WM8oAwV+eN5oExcOgIg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=s+Wh4J4gMjyKf05XjZqCc4Fwht9oDFLYbg6pTsmVkh9FBzXiXdPhq+2arpkfozO2X41E5PCaEewxQDjekq9UawXQ0bfZPf/bPipZ2kqSThmKRUWeMyG6PDS9UY/hqBKbN/ctUoBBrtud2+jRZnt9XzFy5+KW+N+u9nIzmukhs84= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=poczta.fm; spf=pass smtp.mailfrom=poczta.fm; dkim=pass (1024-bit key) header.d=poczta.fm header.i=@poczta.fm header.b=rDOyyIj6; arc=none smtp.client-ip=217.74.67.75 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=poczta.fm Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=poczta.fm Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=poczta.fm header.i=@poczta.fm header.b="rDOyyIj6" Received: from nr200 (unknown [80.68.231.31]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by poczta.interia.pl (INTERIA.PL) with ESMTPSA; Mon, 14 Sep 2026 08:40:45 +0200 (CEST) Date: Mon, 14 Sep 2026 08:40:42 +0200 From: Slawomir Stepien To: Basavaraj Natikar Cc: syzbot , syzkaller-bugs@googlegroups.com, Basavaraj Natikar , Benjamin Tissoires , Jiri Kosina , linux-input@vger.kernel.org, Sandeep Singh , linux-kernel@vger.kernel.org, syzbot@lists.linux.dev Subject: Re: [PATCH] HID: amd_sfh: Validate PCI BAR size before mapping Message-ID: References: <94704655-d654-4500-8122-b80bea9bd908@mail.kernel.org> <7f8690bc-17c7-45e7-bacd-a341b2ef0a4b@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7f8690bc-17c7-45e7-bacd-a341b2ef0a4b@amd.com> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=poczta.fm; s=dk; t=1789368047; bh=35Na2uDYoTkrNh01Rjn3p8QVuDGTu1Bb9xs9LnADGw8=; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type; b=rDOyyIj6aTEe/GmaUS69QFeQXd+EWa2i7Izyyemz+sGAYy7KNqoyYiR5PC6iI1DKJ /rHPq6Liim32PymGFsviz84lD8MGPRBBqZHTMltuAVFJ+FiaYrvdItet0TPEy+Nvqm FB73zZPNYyNHbjc1hSVOpBuqrswDqDK+tM2OWFD8= On wrz 11, 2026 21:33, Basavaraj Natikar wrote: > > On 8/27/2026 12:06 PM, syzbot wrote: > > [You don't often get email from syzbot@kernel.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > > > From: Slawomir Stepien > > > > The amd_sfh driver maps PCI BAR 2 using pcim_iomap_regions() and > > subsequently accesses MMIO registers at offsets up to 0x10958 (e.g., > > AMD_P2C_MSG3 at 0x1068C). However, the driver never validates that the BAR > > size is large enough to cover these accesses. If the driver is bound to a > > device with a smaller BAR 2, this leads to an out-of-bounds memory access > > and a page fault during the probe function. > > > > For example, a page fault can occur when reading from privdata->mmio + > > AMD_P2C_MSG3 in mp2_select_ops(): > > > > BUG: unable to handle page fault for address: ffffc9000390368c > > PGD 100000067 P4D 100000067 PUD 1012c1067 PMD 105b64067 PTE 0 > > Oops: Oops: 0000 [#1] SMP KASAN NOPTI > > RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline] > > RIP: 0010:mp2_select_ops drivers/hid/amd-sfh-hid/amd_sfh_pcie.c:282 > > [inline] > > RIP: 0010:amd_mp2_pci_probe+0x337/0x5f0 > > drivers/hid/amd-sfh-hid/amd_sfh_pcie.c:487 > > Call Trace: > > > > local_pci_probe drivers/pci/pci-driver.c:332 [inline] > > pci_call_probe drivers/pci/pci-driver.c:394 [inline] > > __pci_device_probe drivers/pci/pci-driver.c:455 [inline] > > pci_device_probe+0x431/0xc90 drivers/pci/pci-driver.c:489 > > > > Fix this by verifying that the length of BAR 2 is at least 128KB before > > attempting to map it. Since the maximum accessed offset is 0x10958, and PCI > > BAR sizes are powers of 2, any legitimate hardware will have a BAR size of > > at least 128KB. > > > > Fixes: 4f567b9f8141 ("SFH: PCIe driver to add support of AMD sensor fusion hub") > > Assisted-by: Gemini:gemini-3.7-flash Gemini:gemini-3.1-pro-preview syzbot > > Reported-by: syzbot+4eadd4dfe9e66522bae8@syzkaller.appspotmail.com > > Closes: https://syzkaller.appspot.com/bug?extid=4eadd4dfe9e66522bae8 > > Link: https://syzkaller.appspot.com/ai_job?id=3bc1c45c-548f-4ab5-8243-d2c8ec321d6c > > Signed-off-by: Slawomir Stepien > > > > --- > > diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_common.h b/drivers/hid/amd-sfh-hid/amd_sfh_common.h > > index 78f830c13..c0c324565 100644 > > --- a/drivers/hid/amd-sfh-hid/amd_sfh_common.h > > +++ b/drivers/hid/amd-sfh-hid/amd_sfh_common.h > > @@ -17,6 +17,8 @@ > > #define PCI_DEVICE_ID_AMD_MP2 0x15E4 > > #define PCI_DEVICE_ID_AMD_MP2_1_1 0x164A > > > > +#define AMD_SFH_MIN_BAR_SIZE (128 * 1024) > > Please use SZ_128K instead of the open-coded (128 * 1024), A short comment noting the value > must cover the highest register offset (0x10958) would also help future readers. > > With that: > Acked-by: Basavaraj Natikar Sure, will send v2, thanks! -- Slawomir Stepien