1 files changed, 14 insertions, 8 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index d0fd6c614e68..37efa1f43d8b 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -36,10 +36,16 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	void *src;
 	size_t decomp_size, src_size;
 	u64 decomp_last_rem = 0;
-	size_t decomp_len = session->header.env.comp_mmap_len;
+	size_t mmap_len, decomp_len = session->header.env.comp_mmap_len;
 	struct decomp *decomp, *decomp_last = session->decomp_last;
 
-	decomp = mmap(NULL, sizeof(struct decomp) + decomp_len, PROT_READ|PROT_WRITE,
+	if (decomp_last) {
+		decomp_last_rem = decomp_last->size - decomp_last->head;
+		decomp_len += decomp_last_rem;
+	}
+
+	mmap_len = sizeof(struct decomp) + decomp_len;
+	decomp = mmap(NULL, mmap_len, PROT_READ|PROT_WRITE,
 		      MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 	if (decomp == MAP_FAILED) {
 		pr_err("Couldn't allocate memory for decompression\n");
@@ -47,10 +53,10 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	}
 
 	decomp->file_pos = file_offset;
+	decomp->mmap_len = mmap_len;
 	decomp->head = 0;
 
-	if (decomp_last) {
-		decomp_last_rem = decomp_last->size - decomp_last->head;
+	if (decomp_last_rem) {
 		memcpy(decomp->data, &(decomp_last->data[decomp_last->head]), decomp_last_rem);
 		decomp->size = decomp_last_rem;
 	}
@@ -61,7 +67,7 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	decomp_size = zstd_decompress_stream(&(session->zstd_data), src, src_size,
 				&(decomp->data[decomp_last_rem]), decomp_len - decomp_last_rem);
 	if (!decomp_size) {
-		munmap(decomp, sizeof(struct decomp) + decomp_len);
+		munmap(decomp, mmap_len);
 		pr_err("Couldn't decompress data\n");
 		return -1;
 	}
@@ -255,15 +261,15 @@ static void perf_session__delete_threads(struct perf_session *session)
 static void perf_session__release_decomp_events(struct perf_session *session)
 {
 	struct decomp *next, *decomp;
-	size_t decomp_len;
+	size_t mmap_len;
 	next = session->decomp;
-	decomp_len = session->header.env.comp_mmap_len;
 	do {
 		decomp = next;
 		if (decomp == NULL)
 			break;
 		next = decomp->next;
-		munmap(decomp, decomp_len + sizeof(struct decomp));
+		mmap_len = decomp->mmap_len;
+		munmap(decomp, mmap_len);
 	} while (1);
 }