2013-07-10 19:19:54

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: [PATCH 13/23] perf evsel: Fix count parameter to read call in event_format__new

From: David Ahern <[email protected]>

per realloc above the length of the buffer is alloc_size, not BUFSIZ.
Adjust length per size as done for buf start.

Addresses some valgrind complaints:

==1870== Syscall param read(buf) points to unaddressable byte(s)
==1870== at 0x4E3F610: __read_nocancel (in /lib64/libpthread-2.14.90.so)
==1870== by 0x44AEE1: event_format__new (unistd.h:45)
==1870== by 0x44B025: perf_evsel__newtp (evsel.c:158)
==1870== by 0x451919: add_tracepoint_event (parse-events.c:395)
==1870== by 0x479815: parse_events_parse (parse-events.y:292)
==1870== by 0x45463A: parse_events_option (parse-events.c:861)
==1870== by 0x44FEE4: get_value (parse-options.c:113)
==1870== by 0x450767: parse_options_step (parse-options.c:192)
==1870== by 0x450C40: parse_options (parse-options.c:422)
==1870== by 0x42735F: cmd_record (builtin-record.c:918)
==1870== by 0x419D72: run_builtin (perf.c:319)
==1870== by 0x4195F2: main (perf.c:376)
==1870== Address 0xcffebf0 is 0 bytes after a block of size 8,192 alloc'd
==1870== at 0x4C2A62F: malloc (vg_replace_malloc.c:270)
==1870== by 0x4C2A7A3: realloc (vg_replace_malloc.c:662)
==1870== by 0x44AF07: event_format__new (evsel.c:121)
==1870== by 0x44B025: perf_evsel__newtp (evsel.c:158)
==1870== by 0x451919: add_tracepoint_event (parse-events.c:395)
==1870== by 0x479815: parse_events_parse (parse-events.y:292)
==1870== by 0x45463A: parse_events_option (parse-events.c:861)
==1870== by 0x44FEE4: get_value (parse-options.c:113)
==1870== by 0x450767: parse_options_step (parse-options.c:192)
==1870== by 0x450C40: parse_options (parse-options.c:422)
==1870== by 0x42735F: cmd_record (builtin-record.c:918)
==1870== by 0x419D72: run_builtin (perf.c:319)

Signed-off-by: David Ahern <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/evsel.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 63b6f8c..df99ebe 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -124,7 +124,7 @@ struct event_format *event_format__new(const char *sys, const char *name)
bf = nbf;
}

- n = read(fd, bf + size, BUFSIZ);
+ n = read(fd, bf + size, alloc_size - size);
if (n < 0)
goto out_free_bf;
size += n;
--
1.8.1.4