From nobody Fri Sep 25 10:38:23 2026 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 4F8FE423EB9 for ; Mon, 14 Sep 2026 09:50:37 +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=1789379441; cv=none; b=azUIIsWgw7vuvvQZQ8q2eixTl4KzGHH5cczdnSb02J0G1rsM+9U0wkvm+sAURNNReeL+8uT3un3PkUvQUp8wH4PoYUxVqq1tMevdDJsFpBFqtItcFfwgcJsMTd6z8tJ3VPf768hSjYsAPZ/vLz8dvKDywuJbsnWdtAmZOa7GuCI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789379441; c=relaxed/simple; bh=lOn8gRXqvS7hF+moEVAKdLL/rL+TDs0AzKWVEtTpFUQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=OH/zvqySMT2Iq3Q1hPnBsWfiJdTGMHWyy3HQs4D3/FTbmIIsn7K7lABCiTsbxPSoet3sbzTgF109EWlJ8EcC6++K28iL7+VfN4QBEOElY1GQdAWBCeFCsXe645EIMNbPqgzAE9MTlt/U4oTJMBO8kl+sjMv152cDQvOymsTVJDY= 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=fHSPUpYi; 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="fHSPUpYi" Received: from localhost (unknown [80.68.231.31]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by poczta.interia.pl (INTERIA.PL) with ESMTPSA; Mon, 14 Sep 2026 11:50:33 +0200 (CEST) From: Slawomir Stepien To: syzkaller-bugs@googlegroups.com, Basavaraj Natikar , bentiss@kernel.org, jikos@kernel.org, linux-input@vger.kernel.org, sandeep.singh@amd.com Cc: linux-kernel@vger.kernel.org, syzbot@lists.linux.dev, Slawomir Stepien , syzbot+4eadd4dfe9e66522bae8@syzkaller.appspotmail.com Subject: [PATCH v2] HID: amd_sfh: Validate PCI BAR size before mapping Date: Mon, 14 Sep 2026 11:50:07 +0200 Message-ID: <20260914095007.205287-1-sst@poczta.fm> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=poczta.fm; s=dk; t=1789379434; bh=FVa+YjjcW9hmFc3cvqqLFK8kvWsctFf1lA9TzHiUzRc=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=fHSPUpYimmQJwRXJJMwauDMh4YC2dOr0lbSESJrhIuk8069d6i45hKt1PZOI12pY+ q1qx7CorWSJ+JFttOIXvJmOhobNi+64e6mlbODH/yJIsppO6DSOrYyen9Y2+hcTk+A 6kiugcgEwqnJcqWLRrfPnoWuJhJp/kjdFucx28HY= Content-Type: text/plain; charset="utf-8" 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=3D4eadd4dfe9e66522bae8 Link: https://syzkaller.appspot.com/ai_job?id=3D3bc1c45c-548f-4ab5-8243-d2c= 8ec321d6c Signed-off-by: Slawomir Stepien Acked-by: Basavaraj Natikar --- v2: * Use SZ_128K for AMD_SFH_MIN_BAR_SIZE define * Add comment why we need 128K * Add 'Acked-by: Basavaraj Natikar ' since no lo= gical changes v1: * https://lore.kernel.org/all/94704655-d654-4500-8122-b80bea9bd908@mail.ker= nel.org/ --- drivers/hid/amd-sfh-hid/amd_sfh_common.h | 4 ++++ drivers/hid/amd-sfh-hid/amd_sfh_pcie.c | 10 ++++++++++ 2 files changed, 14 insertions(+) diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_common.h b/drivers/hid/amd-sfh= -hid/amd_sfh_common.h index f8c6b7fc34fb..3d29119a3765 100644 --- a/drivers/hid/amd-sfh-hid/amd_sfh_common.h +++ b/drivers/hid/amd-sfh-hid/amd_sfh_common.h @@ -13,11 +13,15 @@ #include #include #include +#include #include "amd_sfh_hid.h" =20 #define PCI_DEVICE_ID_AMD_MP2 0x15E4 #define PCI_DEVICE_ID_AMD_MP2_1_1 0x164A =20 +/* The BAR 2 size must cover the highest register offset (0x10958) */ +#define AMD_SFH_MIN_BAR_SIZE SZ_128K + #define AMD_C2P_MSG(regno) (0x10500 + ((regno) * 4)) #define AMD_P2C_MSG(regno) (0x10680 + ((regno) * 4)) =20 diff --git a/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c b/drivers/hid/amd-sfh-h= id/amd_sfh_pcie.c index eda26a094d3f..061a63519d44 100644 --- a/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c +++ b/drivers/hid/amd-sfh-hid/amd_sfh_pcie.c @@ -497,6 +497,16 @@ static int amd_mp2_pci_probe(struct pci_dev *pdev, con= st struct pci_device_id *i if (rc) return rc; =20 + if (!(pci_resource_flags(pdev, 2) & IORESOURCE_MEM)) { + dev_err(&pdev->dev, "BAR 2 is not IORESOURCE_MEM\n"); + return -ENODEV; + } + + if (pci_resource_len(pdev, 2) < AMD_SFH_MIN_BAR_SIZE) { + dev_err(&pdev->dev, "BAR 2 is too small\n"); + return -EINVAL; + } + rc =3D pcim_iomap_regions(pdev, BIT(2), DRIVER_NAME); if (rc) return rc; --=20 2.55.0