linux-kernel - [PATCH] perf inject: correct event attribute sizes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201216065816.1840893-1-denik@chromium.org>
Date:   Tue, 15 Dec 2020 22:58:16 -0800
From:   Denis Nikitin <denik@...omium.org>
To:     linux-perf-users@...r.kernel.org, peterz@...radead.org,
        mingo@...hat.com, acme@...nel.org, mark.rutland@....com,
        alexander.shishkin@...ux.intel.com, jolsa@...hat.com,
        namhyung@...nel.org
Cc:     al.grant@....com, al.grant@...s.arm.com,
        linux-kernel@...r.kernel.org, denik@...omium.org
Subject: [PATCH] perf inject: correct event attribute sizes

When perf inject reads a perf.data file from an older version of perf,
it writes event attributes into the output with the original size field,
but lays them out as if they had the size currently used. Readers see
a corrupt file. Update the size field to match the layout.

Signed-off-by: Al Grant <al.grant@...s.arm.com>
Signed-off-by: Denis Nikitin <denik@...omium.org>
---
 tools/perf/util/header.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index be850e9f8852..0d95981df8dd 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3331,6 +3331,14 @@ int perf_session__write_header(struct perf_session *session,
 	attr_offset = lseek(ff.fd, 0, SEEK_CUR);
 
 	evlist__for_each_entry(evlist, evsel) {
+		if (evsel->core.attr.size < sizeof(evsel->core.attr)) {
+			/*
+			 * We are likely in "perf inject" and have read
+			 * from an older file. Update attr size so that
+			 * reader gets the right offset to the ids.
+			 */
+			evsel->core.attr.size = sizeof(evsel->core.attr);
+		}
 		f_attr = (struct perf_file_attr){
 			.attr = evsel->core.attr,
 			.ids  = {
-- 
2.29.2.684.gfbc64c5ab5-goog