From patchwork Thu May 2 22:33:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 13652153 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED32A1B948 for ; Thu, 2 May 2024 22:33:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714689227; cv=none; b=Cdku+RnI1pUPuCFoo3TBPJRdkZB3wXwgB/AhMbqJuYbasImS4oaaVYwHBrhoHB+rUk4cTjWVnOZO+9LnMAdPsKZnW67Z9G2dvrKU3KCmaQG0mSOnPXZoHh0FO9hTD/99BT6rjVJx6gbjGfaMUgBO2FyzWMKfVqYFGjbL+oz6vF0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714689227; c=relaxed/simple; bh=P8oJtedy3HXH20Pj7T8DcdEaOEqGIej1pz81IGBrmfY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=aHyAkCrLoN2VNgx9gK0AazbNqCxUiQcA0ZPWYZqwD9bUDRhnMoXH3eLaqame9XHnKh8NePBNQZem9VrKZ6mLbtGcR3R1iT4YUns0CbVmng1Do3XAviKA4yO8RH+HuDmkhXXrEywweTROmQ1i28tQBJ0p+CokwKt4i5p3OeyG1rc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=IdyzE2iU; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="IdyzE2iU" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-1e834159f40so69524315ad.2 for ; Thu, 02 May 2024 15:33:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1714689225; x=1715294025; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=syonTmYD8c0TYLT7ugjKF/sEjFnMsTQVi6C/fR41bxY=; b=IdyzE2iUNgNuVl5SDzOXszjPPyfM6BIpLvpDd3fgRvRReHLSybEKA2fgrw8R+XaaDN hAJiQi9hb+pk9VnFvinXfag9eyKjHc+c2UujHIhzKvvNEaJknwDbbwjhuMShWgb7ibY6 KrG5/VwKfWO/qywEhttHeDLC3DTLIH3JWxiss= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1714689225; x=1715294025; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=syonTmYD8c0TYLT7ugjKF/sEjFnMsTQVi6C/fR41bxY=; b=Pl0GaGD26tFSpM+cJ/lJyi+i5tZX7wsa/0NRlyjGpS1cnKThvLycRU1+J3SJMUfcv7 8E09hO+K1kcTunClsXOUlAjxg0Xd7Otz5Mgc7B6PTFed/5EOWDUvQ1S8x8jvM/puejXT cvfctkekUQGk/V5/GGKdc0uuRMeW/6o1Y2YwEsR18DOuUiTm2y+gmn8V0WDs8EkmPx2S MNe3idiVlDMQSoOt5CzTdBPhzg/+qz4vT0/duYHP9lCoPOCM+ozqvKN7RfqOcpWsN74n wR2+jcItXmLXNzxMF438C2hSdnjlQYYJlpAF1Xl4+ANkswmA9zM2EhJ0DI5FarKRqXZ4 ybtQ== X-Forwarded-Encrypted: i=1; AJvYcCXfeJSM6bcSnLW+jn6U8OS1ibJWqzMdLSZsZMO5Z2OMc7cMzEOHXWs1psIEI45u2l65oKZE4wUAaMcSI/kJpQBwjB6Ym2n0q77hTNjQKQ== X-Gm-Message-State: AOJu0Yx9NNp2vFF7+NBN+GSgg7X+TsP2XNMSuhyCGkwixifX5SzgqCwD l3iFXtTOTIkHWYkcbFltBi2kmbEj5Dl+eZJ4zIccrS+I+L2mGhXA7/rJ5Bx29A== X-Google-Smtp-Source: AGHT+IEF0+ZDExdwzLRwfCmuME2rfDCoHX3a0jBuTtemcfZavKrmzhzYpowtSNcwJG7mXyaEXL+8xg== X-Received: by 2002:a17:902:bb8d:b0:1e6:68d0:d6c1 with SMTP id m13-20020a170902bb8d00b001e668d0d6c1mr934693pls.40.1714689225425; Thu, 02 May 2024 15:33:45 -0700 (PDT) Received: from www.outflux.net ([198.0.35.241]) by smtp.gmail.com with ESMTPSA id y2-20020a17090264c200b001eb2eac7012sm1885713pli.138.2024.05.02.15.33.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 May 2024 15:33:42 -0700 (PDT) From: Kees Cook To: Christian Brauner Cc: Kees Cook , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , Andi Shyti , Lucas De Marchi , Matt Atwood , Matthew Auld , Nirmoy Das , Jonathan Cavitt , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Al Viro , Jan Kara , Zack Rusin , Broadcom internal kernel review list , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Will Deacon , Peter Zijlstra , Boqun Feng , Mark Rutland , Kent Overstreet , Masahiro Yamada , Nathan Chancellor , Nicolas Schier , Andrew Morton , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH 3/5] drm/i915: Do not directly manipulate file->f_count Date: Thu, 2 May 2024 15:33:38 -0700 Message-Id: <20240502223341.1835070-3-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240502222252.work.690-kees@kernel.org> References: <20240502222252.work.690-kees@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1418; i=keescook@chromium.org; h=from:subject; bh=P8oJtedy3HXH20Pj7T8DcdEaOEqGIej1pz81IGBrmfY=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBmNBTDTJYtS4zv8xaeAG0nbcBc+V98YhNpyJSpC aI+gh9aiHmJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCZjQUwwAKCRCJcvTf3G3A Jj8cD/oDPHTNltydyOxjPKQZBsKvSQLMCwHO4DniBHjFHb53bO32xnSinmbDfMMW6W+37gvrw8+ HE6zUQkGh6uuZsI+sQEoqKgttjLhXt9oHFUm4OxoD0XufetWCTKTscDgXMU1JnsNj8DboYt4rpJ YmSi0hs6QUUf5hOHAUXAKfGs5W7DLp6tpj4rGdmFqMXpkgD3QrChXAj6i8RDdUrhyk9B2pBuY+4 sLgAOFTS0sj9z31xdOO8K3DRa/huLmrWWbAxb8bM8wIR0JFY0lbyIDpDRceiptDZaIJ6SDuE+tn 8hO23F2XRQBqC2khO22JbW5VDa0wCLX1gHTzNFPXb1tP/0vGKwSn9hsEgK1Cs4O8uH/j+XXx3Fu ERZsO42/LUneZufeL5Yn/IXSKnnFBz50uY0DLgUUDbyVaGRt5r41lZ6VS+ICzQdfv0Np/iFVmVj 4QbPjG3GeAvApJNmze6/hNVFC53hBO3XzEb5rZp6CQ0esedaZROBpIP6JhlqTAT/UsP6lYFZCjN mf5dE8DHcNPFgiFNkrVlemIs+i2cWQzPwKMzqlMsJhnW3wYbbkhwnRCZcWpBFOiCxbnTuQiPXd0 MQTHMYZNA3iJPXlf8SU5ArabrMEfY+TNTBgUTOjKDUiIcn8B6Ykj8rc7hA4qkFA9Q3afzMjfC7m Uvjb+C8zzpXuOpg== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 The correct helper for taking an f_count reference is get_file(). Use it and check results. Signed-off-by: Kees Cook --- Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Rodrigo Vivi Cc: Tvrtko Ursulin Cc: David Airlie Cc: Daniel Vetter Cc: Andi Shyti Cc: Lucas De Marchi Cc: Matt Atwood Cc: Matthew Auld Cc: Nirmoy Das Cc: Jonathan Cavitt Cc: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org --- drivers/gpu/drm/i915/gt/shmem_utils.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c index bccc3a1200bc..dc25e6dc884b 100644 --- a/drivers/gpu/drm/i915/gt/shmem_utils.c +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c @@ -38,8 +38,9 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj) void *ptr; if (i915_gem_object_is_shmem(obj)) { - file = obj->base.filp; - atomic_long_inc(&file->f_count); + file = get_file(obj->base.filp); + if (!file) + return ERR_PTR(-ESRCH); return file; }