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 EEEEB1C03 for ; Mon, 20 Mar 2023 15:12:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47F04C433EF; Mon, 20 Mar 2023 15:12:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679325141; bh=7P+Qk8UVbePONM+ocqLe5OYH4QQA7VaeuOo7lQH6DQU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kvmk867j8QR4269Y0iWJjTJdGBbd85NivfkZgBGpDbH3bFP48jYhE7vxasSeoU7Hs Tnu9NnKQfO5NpnOyX/mD2y5HJATSmQc8c3mkMhgEwgFWqScIQxvxNkKJ4Ztu/CckXQ HkmQ+SB15c1b1m5HsTIkIvNjNjAnDIruKDgZP0N8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Emil Renner Berthing , Andrea Righi , Matt Roper , Jani Nikula , Sasha Levin Subject: [PATCH 6.1 045/198] drm/i915/sseu: fix max_subslices array-index-out-of-bounds access Date: Mon, 20 Mar 2023 15:53:03 +0100 Message-Id: <20230320145509.352771021@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230320145507.420176832@linuxfoundation.org> References: <20230320145507.420176832@linuxfoundation.org> User-Agent: quilt/0.67 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 From: Andrea Righi [ Upstream commit 193c41926d152761764894f46e23b53c00186a82 ] It seems that commit bc3c5e0809ae ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") exposed a potential out-of-bounds access, reported by UBSAN as following on a laptop with a gen 11 i915 card: UBSAN: array-index-out-of-bounds in drivers/gpu/drm/i915/gt/intel_sseu.c:65:27 index 6 is out of range for type 'u16 [6]' CPU: 2 PID: 165 Comm: systemd-udevd Not tainted 6.2.0-9-generic #9-Ubuntu Hardware name: Dell Inc. XPS 13 9300/077Y9N, BIOS 1.11.0 03/22/2022 Call Trace: show_stack+0x4e/0x61 dump_stack_lvl+0x4a/0x6f dump_stack+0x10/0x18 ubsan_epilogue+0x9/0x3a __ubsan_handle_out_of_bounds.cold+0x42/0x47 gen11_compute_sseu_info+0x121/0x130 [i915] intel_sseu_info_init+0x15d/0x2b0 [i915] intel_gt_init_mmio+0x23/0x40 [i915] i915_driver_mmio_probe+0x129/0x400 [i915] ? intel_gt_probe_all+0x91/0x2e0 [i915] i915_driver_probe+0xe1/0x3f0 [i915] ? drm_privacy_screen_get+0x16d/0x190 [drm] ? acpi_dev_found+0x64/0x80 i915_pci_probe+0xac/0x1b0 [i915] ... According to the definition of sseu_dev_info, eu_mask->hsw is limited to a maximum of GEN_MAX_SS_PER_HSW_SLICE (6) sub-slices, but gen11_sseu_info_init() can potentially set 8 sub-slices, in the !IS_JSL_EHL(gt->i915) case. Fix this by reserving up to 8 slots for max_subslices in the eu_mask struct. Reported-by: Emil Renner Berthing Signed-off-by: Andrea Righi Fixes: bc3c5e0809ae ("drm/i915/sseu: Don't try to store EU mask internally in UAPI format") Reviewed-by: Matt Roper Signed-off-by: Matt Roper Link: https://patchwork.freedesktop.org/patch/msgid/20230220171858.131416-1-andrea.righi@canonical.com (cherry picked from commit 3cba09a6ac86ea1d456909626eb2685596c07822) Signed-off-by: Jani Nikula Signed-off-by: Sasha Levin --- drivers/gpu/drm/i915/gt/intel_sseu.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.h b/drivers/gpu/drm/i915/gt/intel_sseu.h index aa87d3832d60d..d7e8c374f153e 100644 --- a/drivers/gpu/drm/i915/gt/intel_sseu.h +++ b/drivers/gpu/drm/i915/gt/intel_sseu.h @@ -27,7 +27,7 @@ struct drm_printer; * is only relevant to pre-Xe_HP platforms (Xe_HP and beyond use the * I915_MAX_SS_FUSE_BITS value below). */ -#define GEN_MAX_SS_PER_HSW_SLICE 6 +#define GEN_MAX_SS_PER_HSW_SLICE 8 /* * Maximum number of 32-bit registers used by hardware to express the -- 2.39.2