From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (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 41D822594 for ; Thu, 19 Dec 2024 06:06:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734588417; cv=none; b=KdCC8HVSlyf03PNriAhr5y9XtOtZ+3wMNav1/mJ4pJXYIUvBJQCia6HIWdj5hU5iFkqHj6ql21wSAgaX95VEL88zKtChAqiw/sbyxKZ05Pettgtlbda9fvtwkuy5XAhys3Zq/FPLI7L/ybgVDuMztpIJSxQHUIscmklOrDqPkUE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734588417; c=relaxed/simple; bh=SN/cTD1zFslJ+Inu+KxPuMtZU7sZHDRrEuBxPVFGof0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ngYyW3glBiHQY/yQYZYKKKNoMdZiRMTNg1A3mBz9eO+EfD1gSSE+5QdAExjatnJIO7QzOS+9Dew3XIcDeg5dS3940xfzSD2I0nqdG3kJYLWrdxn3H0M77XGjmzhp9I5mbFShYgR7i/Eu5VD38CYInVNW2CGNQu5nFezbvle6Qv8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=nQ6ZREb6; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="nQ6ZREb6" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-728f1c4b95aso539490b3a.0 for ; Wed, 18 Dec 2024 22:06:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1734588415; x=1735193215; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=nylE0ANEatgw3t8klgiZvXHqMclE1FjmCf3BzEK9MUA=; b=nQ6ZREb6DQNV3gvrqXWH+9uck1aQORS8jXcCpwkMgyDhh3a6uwVR7e4ZnI2WUEoFGb E4htFFpFJuUMTwH70h1tpLXu5f9+fT2urCQhH1fCWpj+p1Ob9nYPjzvNNcpbSfUEyZkr RZ17Jr1OO7Wostzed5OHXBkLiDFurm9/pv5PXiOI8EYKcyLCH8xjGEZ3FTDi08ZPYOsT YfZPvX1v75dzSPdIa7H3YkxV5WxdXyn6zubneeLNVRGbUrVukV9jkGkBTN2Zq5WxBmSD nhP0yD774Iy6bYCNozsZuXgRF2hG92wmL2mX8dbJ198Ue6Ym3ifZwCqs9DMgE9tqeR8/ Jorg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734588415; x=1735193215; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=nylE0ANEatgw3t8klgiZvXHqMclE1FjmCf3BzEK9MUA=; b=nhqcPMJg06IQ0um4AZDkxEc4ayJ0S3IbVh7/aLxbVscWUEpKcIDzxb3WtUuOkPNNN5 jEfG2POYmtAq7GgsTEQHBTSJ1/kGs/8vHVrrAR8bA9J3QKoIorao7I1nOlQaB33LQ4EG KaNmspB2dbXJ6hBdKZfJaP/ELEU1FArXz7VtzSp3swAGm8knPm+fJws4sCXUVK3zc76w tJkrgzsEQbPFNr/EtELG9//xO2eeRMzZE94tR+MnJ+/mzph6u1E9xcSiIkEfGiBYrGjB XzC+QVhO0zxwy9suQUvyVuHKqWWjmrAX97t0f1qZgeM5xb4IA/HGztkQV71++iEUSccf MZTw== X-Gm-Message-State: AOJu0Yw+Rl/6PQM4rJAU0MXOkFbOu6/Aa3ioWuXrRswb+Hv3LR8cQ2Lt spiURVUvmKgFM4/T1Ho7afKCACDSYHgg8QOpVXjZR3/wvHEdFyaNW9jaoFytegbDBjFCoITPpHg llb8CCnPtbxmbBJsybqxq7TrXFseKuzle1EVERN48V8ZysShDrm6hJq34wYQaC/mqNBGh2l4lrT IEiYkzlzbsKBCFVbfL2buxp5hdNa7derqn0SXYJbbXklzA X-Google-Smtp-Source: AGHT+IGx559vrTZpOJE1XZlMPC5dG9+FYwFG5q6SJMVvSXhaW7fSxXwzg9F0FS1C2nUUezk9BJr99r7upQvT X-Received: from pfbhk9.prod.google.com ([2002:a05:6a00:8789:b0:725:e60b:1e4f]) (user=jstultz job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3a02:b0:724:e75b:22d1 with SMTP id d2e1a72fcca58-72a8d2c407bmr6922631b3a.16.1734588415379; Wed, 18 Dec 2024 22:06:55 -0800 (PST) Date: Wed, 18 Dec 2024 22:06:06 -0800 In-Reply-To: <20241219060643.2360926-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241219060643.2360926-1-jstultz@google.com> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog Message-ID: <20241219060643.2360926-2-jstultz@google.com> Subject: [PATCH v3 2/2] lib: stackdepot: Avoid null pointer if stack_depot_save is called too early From: John Stultz To: LKML Cc: John Stultz , Steven Rostedt , Alexander Potapenko , Andrey Konovalov , Andrew Morton , kernel-team@android.com Content-Type: text/plain; charset="UTF-8" If stack_depot_save is called before stackdepot has initialized a null reference to the stack_table might be used, crashing the system. Instead, check stack_table has been initialized before going further. Cc: Steven Rostedt Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrew Morton Cc: kernel-team@android.com Signed-off-by: John Stultz --- lib/stackdepot.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 245d5b4166999..1fe627584535d 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -611,6 +611,9 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries, if (unlikely(nr_entries == 0) || stack_depot_disabled) return 0; + if (!stack_table) + return 0; + hash = hash_stack(entries, nr_entries); bucket = &stack_table[hash & stack_hash_mask]; -- 2.47.1.613.gc27f4b7a9f-goog