From b28e5e439109fe6fd9fa047654ae99d0b7bc5ccc Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Wed, 16 Jun 2021 22:55:54 -0700 Subject: [PATCH] perf daemon: Avoid msan warnings on send_cmd As a full union is always sent, ensure all bytes of the union are initialized with memset to avoid msan warnings of use of uninitialized memory. An example warning from the daemon test: Uninitialized bytes in __interceptor_write at offset 71 inside [0x7ffd98da6280, 72) ==11602==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x5597edccdbe4 in ion tools/lib/perf/lib.c:18:6 #1 0x5597edccdbe4 in writen tools/lib/perf/lib.c:47:9 #2 0x5597ed221d30 in send_cmd tools/perf/builtin-daemon.c:1376:22 #3 0x5597ed21b48c in cmd_daemon tools/perf/builtin-daemon.c #4 0x5597ed1d6b67 in run_builtin tools/perf/perf.c:313:11 #5 0x5597ed1d6036 in handle_internal_command tools/perf/perf.c:365:8 #6 0x5597ed1d6036 in run_argv tools/perf/perf.c:409:2 #7 0x5597ed1d6036 in main tools/perf/perf.c:539:3 SUMMARY: MemorySanitizer: use-of-uninitialized-value tools/lib/perf/lib.c:18:6 in ion Exiting Signed-off-by: Ian Rogers Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210617055554.1917997-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-daemon.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/tools/perf/builtin-daemon.c b/tools/perf/builtin-daemon.c index 61929f63a0474..c13201fb09c3c 100644 --- a/tools/perf/builtin-daemon.c +++ b/tools/perf/builtin-daemon.c @@ -1403,8 +1403,10 @@ static int send_cmd(struct daemon *daemon, union cmd *cmd) static int send_cmd_list(struct daemon *daemon) { - union cmd cmd = { .cmd = CMD_LIST, }; + union cmd cmd; + memset(&cmd, 0, sizeof(cmd)); + cmd.list.cmd = CMD_LIST; cmd.list.verbose = verbose; cmd.list.csv_sep = daemon->csv_sep ? *daemon->csv_sep : 0; @@ -1432,6 +1434,7 @@ static int __cmd_signal(struct daemon *daemon, struct option parent_options[], return -1; } + memset(&cmd, 0, sizeof(cmd)); cmd.signal.cmd = CMD_SIGNAL, cmd.signal.sig = SIGUSR2; strncpy(cmd.signal.name, name, sizeof(cmd.signal.name) - 1); @@ -1446,7 +1449,7 @@ static int __cmd_stop(struct daemon *daemon, struct option parent_options[], OPT_PARENT(parent_options), OPT_END() }; - union cmd cmd = { .cmd = CMD_STOP, }; + union cmd cmd; argc = parse_options(argc, argv, start_options, daemon_usage, 0); if (argc) @@ -1457,6 +1460,8 @@ static int __cmd_stop(struct daemon *daemon, struct option parent_options[], return -1; } + memset(&cmd, 0, sizeof(cmd)); + cmd.cmd = CMD_STOP; return send_cmd(daemon, &cmd); } @@ -1470,7 +1475,7 @@ static int __cmd_ping(struct daemon *daemon, struct option parent_options[], OPT_PARENT(parent_options), OPT_END() }; - union cmd cmd = { .cmd = CMD_PING, }; + union cmd cmd; argc = parse_options(argc, argv, ping_options, daemon_usage, 0); if (argc) @@ -1481,6 +1486,8 @@ static int __cmd_ping(struct daemon *daemon, struct option parent_options[], return -1; } + memset(&cmd, 0, sizeof(cmd)); + cmd.cmd = CMD_PING; scnprintf(cmd.ping.name, sizeof(cmd.ping.name), "%s", name); return send_cmd(daemon, &cmd); }