From d928f8d073f87fdacaf9e93b616f5b84695036e3 Mon Sep 17 00:00:00 2001
From: yangjiaqi <yangjiaqi16@huawei.com>
Date: Wed, 22 Mar 2023 15:31:34 +0800
Subject: [PATCH] proc: fix /proc/diskstats output format

---
 src/proc_fuse.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/proc_fuse.c b/src/proc_fuse.c
index fe81cad..ce22974 100644
--- a/src/proc_fuse.c
+++ b/src/proc_fuse.c
@@ -784,10 +784,10 @@ static int proc_diskstats_read(char *buf, size_t size, off_t offset,
 		memset(lbuf, 0, 256);
 		if (stats.read || stats.write || stats.read_merged || stats.write_merged ||
 		    stats.read_sectors || stats.write_sectors || stats.read_ticks ||
-		    stats.write_ticks || stats.ios_pgr || stats.total_ticks || stats.rq_ticks ||
+		    stats.write_ticks || stats.ios_pgr || stats.total_ticks || stats.rq_ticks || stats.discard ||
 		    stats.discard_merged || stats.discard_sectors || stats.discard_ticks) {
 				if (need_record_diskstats(stats.major, stats.minor)) {
-					sscanf(line, "%u %u %71s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
+					sscanf(line, "%u %u %71s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
 					&stats.major,
 					&stats.minor,
 					tmp_dev_name,
@@ -802,11 +802,12 @@ static int proc_diskstats_read(char *buf, size_t size, off_t offset,
 					&stats.ios_pgr,
 					&stats.total_ticks,
 					&stats.rq_ticks,
+					&stats.discard,
 					&stats.discard_merged,
 					&stats.discard_sectors,
 					&stats.discard_ticks);
 				}
-				snprintf(lbuf, 256, "%u       %u %s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
+				ret = snprintf(lbuf, 256, "%u       %u %s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
 				stats.major,
 				stats.minor,
 				stats.dev_name,
@@ -821,11 +822,17 @@ static int proc_diskstats_read(char *buf, size_t size, off_t offset,
 				stats.ios_pgr,
 				stats.total_ticks,
 				stats.rq_ticks,
+				stats.discard,
 				stats.discard_merged,
 				stats.discard_sectors,
 				stats.discard_ticks);
+				if(ret >= 256) {
+				    lxcfs_error("Insufficient buffer for %u:%u %s diskstats",
+					    stats.major, stats.minor, stats.dev_name);
+				    continue;
+				}
 		} else if (need_record_diskstats(stats.major, stats.minor)) {
-			sscanf(line, "%u %u %71s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
+			sscanf(line, "%u %u %71s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
 				&stats.major,
 				&stats.minor,
 				tmp_dev_name,
@@ -840,10 +847,11 @@ static int proc_diskstats_read(char *buf, size_t size, off_t offset,
 				&stats.ios_pgr,
 				&stats.total_ticks,
 				&stats.rq_ticks,
+				&stats.discard,
 				&stats.discard_merged,
 				&stats.discard_sectors,
 				&stats.discard_ticks);
-			snprintf(lbuf, 256, "%u       %u %s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
+			ret = snprintf(lbuf, 256, "%u       %u %s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
 				stats.major,
 				stats.minor,
 				stats.dev_name,
@@ -858,9 +866,15 @@ static int proc_diskstats_read(char *buf, size_t size, off_t offset,
 				stats.ios_pgr,
 				stats.total_ticks,
 				stats.rq_ticks,
+				stats.discard,
 				stats.discard_merged,
 				stats.discard_sectors,
 				stats.discard_ticks);
+				if(ret >= 256) {
+				    lxcfs_error("Insufficient buffer for %u:%u %s diskstats",
+					    stats.major, stats.minor, stats.dev_name);
+				    continue;
+				}
 		} else {
 			continue;
         }
-- 
2.30.0