2012-08-13 18:38:13

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: [PATCH 29/38] perf symbols: only set vmlinux longname & mark loaded if really loaded

From: Cody P Schafer <[email protected]>

dso__load_vmlinux() uses the filename passed to it to directly set the
dso long_name, which resulted in a use after free due to
dso__load_vmlinux_path() treating 0 symbols as a load failure and
subsequently freeing the contents of dso->long_name.

Change dso__load_vmlinux() so that finding 0 symbols does not cause it
to consider itself loaded, and do not set long_name in such a case.

Signed-off-by: Cody P Schafer <[email protected]>
Cc: David Hansen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Matt Hellsley <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Sukadev Bhattiprolu <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/symbol.c | 7 ++++---
1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index e5c3817..96dbf28 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1364,13 +1364,14 @@ int dso__load_vmlinux(struct dso *dso, struct map *map,
if (fd < 0)
return -1;

- dso__set_long_name(dso, (char *)vmlinux);
- dso__set_loaded(dso, map->type);
err = dso__load_sym(dso, map, symfs_vmlinux, fd, filter, 0, 0);
close(fd);

- if (err > 0)
+ if (err > 0) {
+ dso__set_long_name(dso, (char *)vmlinux);
+ dso__set_loaded(dso, map->type);
pr_debug("Using %s for symbols\n", symfs_vmlinux);
+ }

return err;
}
--
1.7.1