From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7FFF734AB03 for ; Sun, 6 Sep 2026 01:44:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788659055; cv=none; b=VGEvaHXYbqc+6JK0Cm4oZ21iOqPHY/NgOFLjted0i4XftV543mZ/9YvS0jwHbvrTcBXtj8PZnsR4znBLhU2lWu0vrLedtq7L5LPAUgFk8bzQ8qhg5GreQ5a4e3wzt0KF251xNupRqO5lrimEPRJD6AZfaR6uhUgCo2tP4IajRHA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788659055; c=relaxed/simple; bh=F6KQeZdbVNU6nqzdbwbqOcfr7MGeBxYJ/WbkW5sRG8c=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=HdF0qjeUnVdsvArx73fUpq0ctV/tH0TYJ1oTlOU4niy+bGyL0BMINa0Bgbw4DByjJJaRT/Lz2QecgyWEwuIFf/vDXx2Y2dohI/rkcoZ/ZB5rgr7FTX9UQAWxT1Wj25SHqZrnjIlXMkE+ccsrrwM2tjojQsAentwqti3dyeebDHg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ePtKCJD6; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ePtKCJD6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 453431F00A3A; Sun, 6 Sep 2026 01:44:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788659054; bh=zLOsuJy/tiOhVClCFWf0RybPYTPcY6Fl4v6aNVup9Uo=; h=Date:From:To:Cc:Subject:References; b=ePtKCJD69ISrOnx53xRoYrhKz9sVf2wt9hU/JG0D9e/P9edTx8OeeZyd9A4D0uAMk GdTW13/rocmwUIGWShXoerO6XLtHOCTN/KnrHyeS5puFvWN/O2kN5WYMu3rVwQlRhn +8Of4G62Ej3iydkDnzrEel8hMivVUGeeskOqxLizUO8Rqgdc2OCmnp/cY1meaTNzfb FG3tJFITVUar/HyavEojSLxCX+kI3VgSnpG/XP2j/Au9L10gZjS4RlV17F3Hk2PElm cz6MpcUPphfmvy0FuBV9cdTUBajAbvAdtBw84HgHPuSLOmacXaGvFw07wVfpCDWXcF rfV509cZCO/xg== Received: from rostedt by gandalf with local (Exim 4.99.4) (envelope-from ) id 1x2whP-00000006JBB-3YsZ; Sat, 05 Sep 2026 16:09:15 -0400 Message-ID: <20260905200915.717678123@kernel.org> User-Agent: quilt/0.69 Date: Sat, 05 Sep 2026 16:08:33 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Vincent Donnefort , sashiko-bot@kernel.org Subject: [for-linus][PATCH 06/12] ring-buffer: Add checking nr_subbufs to persistent ring buffer validation References: <20260905200827.773347757@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Steven Rostedt Sashiko reported that the code was using meta->nr_subbufs without making sure that it matched the nr_pages + 1 on data that was assuming the two were the same. Add a check to the persistent ring buffer validation code to make sure that the saved nr_subbufs matches what we expect. Link: https://patch.msgid.link/20260903132728.7fb27d34@gandalf.local.home Fixes: f5b95f1fa2ef3 ("ring-buffer: Validate the persistent meta data subbuf array") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/all/20260901164836.D962D1F000E9@smtp.kernel.org/ Reviewed-by: Vincent Donnefort Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 84fd4cdd486f..ff0a44aa578d 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1856,6 +1856,11 @@ static bool rb_cpu_meta_valid(struct ring_buffer_cpu_meta *meta, int cpu, return false; } + if (meta->nr_subbufs != nr_pages + 1) { + pr_info("Ring buffer boot meta [%d] invalid nr_subbufs\n", cpu); + return false; + } + buffers_start = meta->first_buffer; buffers_end = meta->first_buffer + (subbuf_size * meta->nr_subbufs); -- 2.53.0