1 files changed, 27 insertions, 17 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index f07b8ecb91bc..8454a650146b 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1958,8 +1958,8 @@ out_err:
 }
 
 static union perf_event *
-fetch_mmaped_event(struct perf_session *session,
-		   u64 head, size_t mmap_size, char *buf)
+prefetch_event(char *buf, u64 head, size_t mmap_size,
+	       bool needs_swap, union perf_event *error)
 {
 	union perf_event *event;
 
@@ -1971,20 +1971,32 @@ fetch_mmaped_event(struct perf_session *session,
 		return NULL;
 
 	event = (union perf_event *)(buf + head);
+	if (needs_swap)
+		perf_event_header__bswap(&event->header);
 
-	if (session->header.needs_swap)
+	if (head + event->header.size <= mmap_size)
+		return event;
+
+	/* We're not fetching the event so swap back again */
+	if (needs_swap)
 		perf_event_header__bswap(&event->header);
 
-	if (head + event->header.size > mmap_size) {
-		/* We're not fetching the event so swap back again */
-		if (session->header.needs_swap)
-			perf_event_header__bswap(&event->header);
-		pr_debug("%s: head=%#" PRIx64 " event->header_size=%#x, mmap_size=%#zx: fuzzed perf.data?\n",
-			 __func__, head, event->header.size, mmap_size);
-		return ERR_PTR(-EINVAL);
-	}
+	pr_debug("%s: head=%#" PRIx64 " event->header_size=%#x, mmap_size=%#zx:"
+		 " fuzzed or compressed perf.data?\n",__func__, head, event->header.size, mmap_size);
 
-	return event;
+	return error;
+}
+
+static union perf_event *
+fetch_mmaped_event(u64 head, size_t mmap_size, char *buf, bool needs_swap)
+{
+	return prefetch_event(buf, head, mmap_size, needs_swap, ERR_PTR(-EINVAL));
+}
+
+static union perf_event *
+fetch_decomp_event(u64 head, size_t mmap_size, char *buf, bool needs_swap)
+{
+	return prefetch_event(buf, head, mmap_size, needs_swap, NULL);
 }
 
 static int __perf_session__process_decomp_events(struct perf_session *session)
@@ -1997,10 +2009,8 @@ static int __perf_session__process_decomp_events(struct perf_session *session)
 		return 0;
 
 	while (decomp->head < decomp->size && !session_done()) {
-		union perf_event *event = fetch_mmaped_event(session, decomp->head, decomp->size, decomp->data);
-
-		if (IS_ERR(event))
-			return PTR_ERR(event);
+		union perf_event *event = fetch_decomp_event(decomp->head, decomp->size, decomp->data,
+							     session->header.needs_swap);
 
 		if (!event)
 			break;
@@ -2100,7 +2110,7 @@ remap:
 	}
 
 more:
-	event = fetch_mmaped_event(session, head, mmap_size, buf);
+	event = fetch_mmaped_event(head, mmap_size, buf, session->header.needs_swap);
 	if (IS_ERR(event))
 		return PTR_ERR(event);