From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (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 B8E192107 for ; Sat, 16 Nov 2024 00:23:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731716613; cv=none; b=Sel/PpOH5706ajZDWGCoE+A7bV/WPaRSDXXarWzsBSJUJ/rA4w4jO6fv55usBSU+Dgs2QBkPlDGv45HWe5Fy5MOpbQ5bmuaHGKBsyVYBxGix+arlxkviFTx3PAwB13s09S+Mnzv2NSbg887Elq633wzdNjU/YmctjxaffmVXkb8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731716613; c=relaxed/simple; bh=WmS8zxT2Q1jka+KaHMF71D3onWxqZXl2ZWo6Thqnv24=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=YeSfOVhSh8uwlbqnrq5drHV/gZIJJLDSJ/DEmkGqZHbhU3Ah1Zp3sYfmHPC5maFDWpRWqSAeZ0GMPYbuHd2eHv2GdeQAcn+AWwukLBLk8JZWzW91rKMF4/OQqYeWful+GaZ70QoSULHhHwa6+bhdwt9+rO/UEyjmBUGksvyLJLc= 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=KJ3Sz5Z3; arc=none smtp.client-ip=209.85.216.73 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="KJ3Sz5Z3" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-2ea3512feaeso265720a91.2 for ; Fri, 15 Nov 2024 16:23:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1731716611; x=1732321411; 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=mAISKCygyKfiQBAPwtOOB4Nt2ymKuY8x1KhZAspiXJk=; b=KJ3Sz5Z3oIXvQPTnEQ1jv7NxBpaxnY5e7wr+XobSD60usLx+OHsgwFxiGrVGAM3p+5 2RolSqXgg0qOmhx4rOQXhusWuIqcr5qUFbvyG943p/NflzIZEuIXDporbvWtUfJhE4Lb 6HlFomgzNAdStkGMCChSK/IPyXW5cUffgBalQrvbGJTEBiHS0HNfnH3swBWJ66aRU9F7 hSj2+JMIr+vQKe3JNTRidFdC0j3R6+URDoTSo+aZ8g7JlcNE2iwGMU8BseXiJTr/+Ogu 0EQKB9JzHfXoJrxSLsWvO6tQLXRU58tg1u8vXfFaPT6m68HRQW6g1ODbkrcrYRmF48pf HkaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731716611; x=1732321411; 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=mAISKCygyKfiQBAPwtOOB4Nt2ymKuY8x1KhZAspiXJk=; b=tc3VuRk3K37KZncgNw+6JDfQORD0sN4bSu4YUU38tsHx+uYIbzpk6ZG8OMso0qk7K/ gMr1DUJg3CroHQDnPOFyWnrQ/EJQW+MSpZDQEft9wMOA7i8N0QH2SzQW8ruPqzcDouI5 GqVwMkgAKdRnVe8JM+6gWxqd75mHK+LO4vXe27LA9laCyCFbRL0h/XAjIw0Dv0o7gDgo +F4aXVjU+QmHP/SeenbdSRSTrA3CZ81avmOhPZFwygvGHgYAS3iV4Np0xYSP9sTzrGOc F3icirxI71lbmNwW3tRuvheZ5I9oYahSzm5LjbE4fGFH5/iPFe8PCtQPTOPBy1P9h9No qM/A== X-Gm-Message-State: AOJu0YyZ6qrhcI8u+J14KGbHTjlvJCpvh1X6/VWt5fcFP1a6rWqBMqHO 4h/lj3xTctRoq8dGhKTUUzSJBs2SzKRRcHoYHonGcHDk8mCIAlSt6sGxt0fGNeAukaARMkfwOx/ 8gi01keKNeIej8G9AoGfjIyiM1YUlhsDHQnc7VAkHQmuohLe5blZRsXfue1BJnOIRwDy1HgfDNz xyJE4TZZHsnsynRha1AKlAhMYRjeiWU7AbBHfFIJ6faqG0 X-Google-Smtp-Source: AGHT+IGr0l6UsZgGwMT35aAhg8C7sVqD2sj0qJzMrrVgYieTOOz6I+qWRoA7NuiQlbYXeHiYWEpFlbsr70Ns X-Received: from jstultz-noogler2.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:600]) (user=jstultz job=sendgmr) by 2002:a17:90a:ff04:b0:2ea:3177:f017 with SMTP id 98e67ed59e1d1-2ea3177f170mr2524a91.1.1731716610858; Fri, 15 Nov 2024 16:23:30 -0800 (PST) Date: Fri, 15 Nov 2024 16:23:07 -0800 In-Reply-To: <20241116002322.1035417-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241116002322.1035417-1-jstultz@google.com> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Message-ID: <20241116002322.1035417-2-jstultz@google.com> Subject: [PATCH v2 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 5ed34cc963fc..09780c835362 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]; -- 2.47.0.338.g60cca15819-goog