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 0DA9C381D1 for ; Wed, 15 Nov 2023 20:00:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="S4+cr30D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1F16C433C7; Wed, 15 Nov 2023 20:00:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1700078446; bh=hFGLgSYKODDJ049/fpk4wWz4nbJA/vcePD0m/PXXdgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S4+cr30DJGzDnbjseQO+LULG93qtD/OrQtEaIUeH1parbX0pKWkEHcRBSc5Q3F5CQ wACCZzHdArrHk+2gtv5I4o8zVVj5CA3d1hYEDC1Tt4FA6o/ciHJV+axeeew3KUp2V2 neiz71f+0VDctT3rDoub+kEf75ZC4fWlqD9HDdY0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ian Rogers , K Prateek Nayak , Ravi Bangoria , Sandipan Das , Anshuman Khandual , German Gomez , James Clark , Nick Terrell , Sean Christopherson , Changbin Du , liuwenyu , Yang Jihong , Masami Hiramatsu , Miguel Ojeda , Song Liu , Leo Yan , Kajol Jain , Andi Kleen , Kan Liang , Athira Rajeev , Yanteng Si , Liam Howlett , Paolo Bonzini , Namhyung Kim , Sasha Levin Subject: [PATCH 6.1 302/379] perf machine: Avoid out of bounds LBR memory read Date: Wed, 15 Nov 2023 14:26:17 -0500 Message-ID: <20231115192703.009775703@linuxfoundation.org> X-Mailer: git-send-email 2.42.1 In-Reply-To: <20231115192645.143643130@linuxfoundation.org> References: <20231115192645.143643130@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Rogers [ Upstream commit ab8ce150781d326c6bfbe1e09f175ffde1186f80 ] Running perf top with address sanitizer and "--call-graph=lbr" fails due to reading sample 0 when no samples exist. Add a guard to prevent this. Fixes: e2b23483eb1d ("perf machine: Factor out lbr_callchain_add_lbr_ip()") Signed-off-by: Ian Rogers Cc: K Prateek Nayak Cc: Ravi Bangoria Cc: Sandipan Das Cc: Anshuman Khandual Cc: German Gomez Cc: James Clark Cc: Nick Terrell Cc: Sean Christopherson Cc: Changbin Du Cc: liuwenyu Cc: Yang Jihong Cc: Masami Hiramatsu Cc: Miguel Ojeda Cc: Song Liu Cc: Leo Yan Cc: Kajol Jain Cc: Andi Kleen Cc: Kan Liang Cc: Athira Rajeev Cc: Yanteng Si Cc: Liam Howlett Cc: Paolo Bonzini Link: https://lore.kernel.org/r/20231024222353.3024098-3-irogers@google.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin --- tools/perf/util/machine.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 76316e459c3de..9cd52f50ea7ac 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2555,16 +2555,18 @@ static int lbr_callchain_add_lbr_ip(struct thread *thread, save_lbr_cursor_node(thread, cursor, i); } - /* Add LBR ip from first entries.to */ - ip = entries[0].to; - flags = &entries[0].flags; - *branch_from = entries[0].from; - err = add_callchain_ip(thread, cursor, parent, - root_al, &cpumode, ip, - true, flags, NULL, - *branch_from); - if (err) - return err; + if (lbr_nr > 0) { + /* Add LBR ip from first entries.to */ + ip = entries[0].to; + flags = &entries[0].flags; + *branch_from = entries[0].from; + err = add_callchain_ip(thread, cursor, parent, + root_al, &cpumode, ip, + true, flags, NULL, + *branch_from); + if (err) + return err; + } return 0; } -- 2.42.0