perf symbols: Allow forcing reading of non-root owned files by root

When the root user tries to read a file owned by some other user we get:

  # ls -la perf.data
  -rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data
  # perf report
  File perf.data not owned by current user or root (use -f to override)
  # perf report -f | grep -v ^# | head -2
    30.96%  ls       [kernel.vmlinux]  [k] do_set_pte
    28.24%  ls       libc-2.20.so      [.] intel_check_word
  #

That wasn't happening when the symbol code tried to read a JIT map,
where the same check was done but no forcing was possible, fix it.

Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2380
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 09343a880c0b..cd08027a6d2c 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1436,9 +1436,9 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 		if (lstat(dso->name, &st) < 0)
 			goto out;
 
-		if (st.st_uid && (st.st_uid != geteuid())) {
+		if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
 			pr_warning("File %s not owned by current user or root, "
-				"ignoring it.\n", dso->name);
+				   "ignoring it (use -f to override).\n", dso->name);
 			goto out;
 		}