perf header: Ensure read/write finished successfully

Use readn instead of read and check return value of do_write.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1355726345-29553-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/header.c

@@ -148,7 +148,7 @@ static char *do_read_string(int fd, struct perf_header *ph)
 	u32 len;
 	char *buf;
 
-	sz = read(fd, &len, sizeof(len));
+	sz = readn(fd, &len, sizeof(len));
 	if (sz < (ssize_t)sizeof(len))
 		return NULL;
 
@@ -159,7 +159,7 @@ static char *do_read_string(int fd, struct perf_header *ph)
 	if (!buf)
 		return NULL;
 
-	ret = read(fd, buf, len);
+	ret = readn(fd, buf, len);
 	if (ret == (ssize_t)len) {
 		/*
 		 * strings are padded by zeroes
@@ -1051,16 +1051,25 @@ static int write_pmu_mappings(int fd, struct perf_header *h __maybe_unused,
 	struct perf_pmu *pmu = NULL;
 	off_t offset = lseek(fd, 0, SEEK_CUR);
 	__u32 pmu_num = 0;
+	int ret;
 
 	/* write real pmu_num later */
-	do_write(fd, &pmu_num, sizeof(pmu_num));
+	ret = do_write(fd, &pmu_num, sizeof(pmu_num));
+	if (ret < 0)
+		return ret;
 
 	while ((pmu = perf_pmu__scan(pmu))) {
 		if (!pmu->name)
 			continue;
 		pmu_num++;
-		do_write(fd, &pmu->type, sizeof(pmu->type));
-		do_write_string(fd, pmu->name);
+
+		ret = do_write(fd, &pmu->type, sizeof(pmu->type));
+		if (ret < 0)
+			return ret;
+
+		ret = do_write_string(fd, pmu->name);
+		if (ret < 0)
+			return ret;
 	}
 
 	if (pwrite(fd, &pmu_num, sizeof(pmu_num), offset) != sizeof(pmu_num)) {
@@ -1209,14 +1218,14 @@ read_event_desc(struct perf_header *ph, int fd)
 	size_t msz;
 
 	/* number of events */
-	ret = read(fd, &nre, sizeof(nre));
+	ret = readn(fd, &nre, sizeof(nre));
 	if (ret != (ssize_t)sizeof(nre))
 		goto error;
 
 	if (ph->needs_swap)
 		nre = bswap_32(nre);
 
-	ret = read(fd, &sz, sizeof(sz));
+	ret = readn(fd, &sz, sizeof(sz));
 	if (ret != (ssize_t)sizeof(sz))
 		goto error;
 
@@ -1244,7 +1253,7 @@ read_event_desc(struct perf_header *ph, int fd)
 		 * must read entire on-file attr struct to
 		 * sync up with layout.
 		 */
-		ret = read(fd, buf, sz);
+		ret = readn(fd, buf, sz);
 		if (ret != (ssize_t)sz)
 			goto error;
 
@@ -1253,7 +1262,7 @@ read_event_desc(struct perf_header *ph, int fd)
 
 		memcpy(&evsel->attr, buf, msz);
 
-		ret = read(fd, &nr, sizeof(nr));
+		ret = readn(fd, &nr, sizeof(nr));
 		if (ret != (ssize_t)sizeof(nr))
 			goto error;
 
@@ -1274,7 +1283,7 @@ read_event_desc(struct perf_header *ph, int fd)
 		evsel->id = id;
 
 		for (j = 0 ; j < nr; j++) {
-			ret = read(fd, id, sizeof(*id));
+			ret = readn(fd, id, sizeof(*id));
 			if (ret != (ssize_t)sizeof(*id))
 				goto error;
 			if (ph->needs_swap)
@@ -1506,14 +1515,14 @@ static int perf_header__read_build_ids_abi_quirk(struct perf_header *header,
 	while (offset < limit) {
 		ssize_t len;
 
-		if (read(input, &old_bev, sizeof(old_bev)) != sizeof(old_bev))
+		if (readn(input, &old_bev, sizeof(old_bev)) != sizeof(old_bev))
 			return -1;
 
 		if (header->needs_swap)
 			perf_event_header__bswap(&old_bev.header);
 
 		len = old_bev.header.size - sizeof(old_bev);
-		if (read(input, filename, len) != len)
+		if (readn(input, filename, len) != len)
 			return -1;
 
 		bev.header = old_bev.header;
@@ -1548,14 +1557,14 @@ static int perf_header__read_build_ids(struct perf_header *header,
 	while (offset < limit) {
 		ssize_t len;
 
-		if (read(input, &bev, sizeof(bev)) != sizeof(bev))
+		if (readn(input, &bev, sizeof(bev)) != sizeof(bev))
 			goto out;
 
 		if (header->needs_swap)
 			perf_event_header__bswap(&bev.header);
 
 		len = bev.header.size - sizeof(bev);
-		if (read(input, filename, len) != len)
+		if (readn(input, filename, len) != len)
 			goto out;
 		/*
 		 * The a1645ce1 changeset:
@@ -1641,7 +1650,7 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
 	size_t ret;
 	u32 nr;
 
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		return -1;
 
@@ -1650,7 +1659,7 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
 
 	ph->env.nr_cpus_online = nr;
 
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		return -1;
 
@@ -1684,7 +1693,7 @@ static int process_total_mem(struct perf_file_section *section __maybe_unused,
 	uint64_t mem;
 	size_t ret;
 
-	ret = read(fd, &mem, sizeof(mem));
+	ret = readn(fd, &mem, sizeof(mem));
 	if (ret != sizeof(mem))
 		return -1;
 
@@ -1756,7 +1765,7 @@ static int process_cmdline(struct perf_file_section *section __maybe_unused,
 	u32 nr, i;
 	struct strbuf sb;
 
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		return -1;
 
@@ -1792,7 +1801,7 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 	char *str;
 	struct strbuf sb;
 
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		return -1;
 
@@ -1813,7 +1822,7 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 	}
 	ph->env.sibling_cores = strbuf_detach(&sb, NULL);
 
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		return -1;
 
@@ -1850,7 +1859,7 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 	struct strbuf sb;
 
 	/* nr nodes */
-	ret = read(fd, &nr, sizeof(nr));
+	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
 		goto error;
 
@@ -1862,15 +1871,15 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 
 	for (i = 0; i < nr; i++) {
 		/* node number */
-		ret = read(fd, &node, sizeof(node));
+		ret = readn(fd, &node, sizeof(node));
 		if (ret != sizeof(node))
 			goto error;
 
-		ret = read(fd, &mem_total, sizeof(u64));
+		ret = readn(fd, &mem_total, sizeof(u64));
 		if (ret != sizeof(u64))
 			goto error;
 
-		ret = read(fd, &mem_free, sizeof(u64));
+		ret = readn(fd, &mem_free, sizeof(u64));
 		if (ret != sizeof(u64))
 			goto error;
 
@@ -1909,7 +1918,7 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 	u32 type;
 	struct strbuf sb;
 
-	ret = read(fd, &pmu_num, sizeof(pmu_num));
+	ret = readn(fd, &pmu_num, sizeof(pmu_num));
 	if (ret != sizeof(pmu_num))
 		return -1;
 
@@ -1925,7 +1934,7 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 	strbuf_init(&sb, 128);
 
 	while (pmu_num) {
-		if (read(fd, &type, sizeof(type)) != sizeof(type))
+		if (readn(fd, &type, sizeof(type)) != sizeof(type))
 			goto error;
 		if (ph->needs_swap)
 			type = bswap_32(type);
@@ -2912,7 +2921,7 @@ int perf_event__process_tracing_data(union perf_event *event,
 				 session->repipe);
 	padding = PERF_ALIGN(size_read, sizeof(u64)) - size_read;
 
-	if (read(session->fd, buf, padding) < 0)
+	if (readn(session->fd, buf, padding) < 0)
 		die("reading input file");
 	if (session->repipe) {
 		int retw = write(STDOUT_FILENO, buf, padding);