From: Arnaldo Carvalho de Melo <[email protected]>

It shouldn't be zero, but if the 'perf probe' on getname_flags() (or
elsewhere in the future we need to probe to catch the pathname for
syscalls like 'open' being copied from userspace to the kernel) is
misplaced somehow, then we will end up not allocating space and trying
to copy the "" empty string to ttrace->filename.name, causing a
segfault, fix it.

Cc: Adrian Hunter <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Wang Nan <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
 tools/perf/builtin-trace.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 912fedc5b42d..33c657c15d5e 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1656,6 +1656,8 @@ static int trace__vfs_getname(struct trace *trace, struct 
perf_evsel *evsel,
                goto out;
 
        filename_len = strlen(filename);
+       if (filename_len == 0)
+               goto out;
 
        if (ttrace->filename.namelen < filename_len) {
                char *f = realloc(ttrace->filename.name, filename_len + 1);
-- 
2.9.3

Reply via email to