From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpo63.interia.pl (smtpo63.interia.pl [217.74.67.63]) (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 D3FE41DD0EF for ; Wed, 26 Aug 2026 06:38:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.74.67.63 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787726340; cv=none; b=RIGEHn9stmtDro2ZhyUHhXrXZZEEb3vfvRMG/kShzwHnzEue6eJqLRFl8aGyABCLUNxzUtkICU+puN7QdWKCxM9MPLUzAae6yKw28wqstxbDyG6tw+CFUIu846ZV0tOlgVeGJ94h+dr3WuZTV3zGVflI2mYqOpWC1keOPCnoD3g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787726340; c=relaxed/simple; bh=KXmKL8KJ+ycCnq/XMq3Uum6Poztcc258idf2uxMQ/0s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Si7iumughkYAcJF8fxecYZ23wELukdS0gvNa6rzAm1jZSRZSGOdGUdaXTVslRFY2QlEaJWZvdUsX2pLi5k3w+z9mYPuEe1GzneLekrIOyFwZPTyo+X4Un5RQURAK1tAyyPe6StpWDvoYjCiPI8mpFM4GlwE86UcWPE5yTKxaGRk= 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=H1bsou50; arc=none smtp.client-ip=217.74.67.63 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="H1bsou50" 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; Wed, 26 Aug 2026 08:38:51 +0200 (CEST) Date: Wed, 26 Aug 2026 08:38:50 +0200 From: Slawomir Stepien To: syzbot Cc: syzkaller-upstream-moderation@googlegroups.com, syzbot@lists.linux.dev Subject: Re: [PATCH RFC] HID: amd_sfh: Validate PCI BAR size before mapping Message-ID: References: Precedence: bulk X-Mailing-List: syzbot@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=poczta.fm; s=dk; t=1787726332; bh=JO+WoPSuAqo24O08LwH4q8QMXVBhfgSHMD5N0uX/8MQ=; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type; b=H1bsou50f3FkhfUDp0A/q6M/MYefGy12spXySlihwYm48W/n7eFrUEXgl/2VVqNEe DnNvAVjLXPpMRhCI5YtSZtg6TWBMjVSp7YTV1kdqy+bVPS+CaVHyphGiVkmcgQahNU 9uzsqhkdch+9ogco6RJ/Xx64AAWHFrPX80hfwXv0= On sie 13, 2026 20:44, 'syzbot' via syzkaller-upstream-moderation wrote: > 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-3.6-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=7a94b74c-2359-4cbe-b08b-2c52f3bf9755 > To: "Basavaraj Natikar" > To: "Benjamin Tissoires" > To: "Jiri Kosina" > To: > To: "Sandeep Singh" > Cc: > > --- > diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c b/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c > index 4b81cebdc..c1dbee87c 100644 > --- a/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c > +++ b/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c > @@ -451,6 +451,11 @@ static int amd_mp2_pci_probe(struct pci_dev *pdev, const struct pci_device_id *i > if (rc) > return rc; > > + if (pci_resource_len(pdev, 2) < 128 * 1024) { Put this 128 * 1024 as some nice #define. > + dev_err(&pdev->dev, "BAR 2 is too small\n"); > + return -EINVAL; > + } > + > rc = pcim_iomap_regions(pdev, BIT(2), DRIVER_NAME); > if (rc) > return rc; > > > base-commit: db2ddb87143519e20a95aa36c60b36107b736a58 -- Slawomir Stepien