From: "Steven Rostedt (VMware)" rostedt@goodmis.org
[ Upstream commit d777f8de99b05d399c0e4e51cdce016f26bd971b ]
If a field is a dynamic string, get_field_str() returned just the offset/size value and not the string. Have it parse the offset/size correctly to return the actual string. Otherwise filtering fails when trying to filter fields that are dynamic strings.
Reported-by: Gopanapalli Pradeep prap_hai@yahoo.com Signed-off-by: Steven Rostedt rostedt@goodmis.org Acked-by: Namhyung Kim namhyung@kernel.org Cc: Andrew Morton akpm@linux-foundation.org Link: http://lkml.kernel.org/r/20180112004823.146333275@goodmis.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- tools/lib/traceevent/parse-filter.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/tools/lib/traceevent/parse-filter.c b/tools/lib/traceevent/parse-filter.c index 7c214ceb9386..5e10ba796a6f 100644 --- a/tools/lib/traceevent/parse-filter.c +++ b/tools/lib/traceevent/parse-filter.c @@ -1879,17 +1879,25 @@ static const char *get_field_str(struct filter_arg *arg, struct pevent_record *r struct pevent *pevent; unsigned long long addr; const char *val = NULL; + unsigned int size; char hex[64];
/* If the field is not a string convert it */ if (arg->str.field->flags & FIELD_IS_STRING) { val = record->data + arg->str.field->offset; + size = arg->str.field->size; + + if (arg->str.field->flags & FIELD_IS_DYNAMIC) { + addr = *(unsigned int *)val; + val = record->data + (addr & 0xffff); + size = addr >> 16; + }
/* * We need to copy the data since we can't be sure the field * is null terminated. */ - if (*(val + arg->str.field->size - 1)) { + if (*(val + size - 1)) { /* copy it */ memcpy(arg->str.buffer, val, arg->str.field->size); /* the buffer is already NULL terminated */