From: John L. Hammond <jhammond@whamcloud.com>
Date: Fri, 14 Sep 2018 20:49:37 +0000 (-0500)
Subject: LU-11380 llite: zero lum for stripeless files
X-Git-Tag: 2.11.56~33
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=refs%2Fchanges%2F72%2F33172%2F3;p=fs%2Flustre-release.git

LU-11380 llite: zero lum for stripeless files

In the IOC_MDC_GETFILEINFO/LL_IOC_MDC_GETINFO case of ll_dir_ioctl(),
if the file has no striping then zero out the lum buffer so that
userspace won't be confused by garbage.

Signed-off-by: John L. Hammond <jhammond@whamcloud.com>
Change-Id: I4574b8bfdee122ec1ac571ae3714026c6fa0a7f0
Reviewed-on: https://review.whamcloud.com/33172
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
---

diff --git a/lustre/llite/dir.c b/lustre/llite/dir.c
index cb73a4d..9e07036 100644
--- a/lustre/llite/dir.c
+++ b/lustre/llite/dir.c
@@ -1514,13 +1514,14 @@ out_rmdir:
                         GOTO(out_req, rc);
                 }
 
-                if (rc < 0) {
-                        if (rc == -ENODATA && (cmd == IOC_MDC_GETFILEINFO ||
-                                               cmd == LL_IOC_MDC_GETINFO))
-                                GOTO(skip_lmm, rc = 0);
-                        else
-                                GOTO(out_req, rc);
-                }
+		if (rc == -ENODATA && (cmd == IOC_MDC_GETFILEINFO ||
+				       cmd == LL_IOC_MDC_GETINFO)) {
+			lmmsize = 0;
+			rc = 0;
+		}
+
+		if (rc < 0)
+			GOTO(out_req, rc);
 
 		if (cmd == IOC_MDC_GETFILESTRIPE ||
 		    cmd == LL_IOC_LOV_GETSTRIPE ||
@@ -1531,12 +1532,18 @@ out_rmdir:
 			lmdp = (struct lov_user_mds_data __user *)arg;
                         lump = &lmdp->lmd_lmm;
                 }
-		if (copy_to_user(lump, lmm, lmmsize)) {
+
+		if (lmmsize == 0) {
+			/* If the file has no striping then zero out *lump so
+			 * that the caller isn't confused by garbage. */
+			if (clear_user(lump, sizeof(*lump)))
+				GOTO(out_req, rc = -EFAULT);
+		} else if (copy_to_user(lump, lmm, lmmsize)) {
 			if (copy_to_user(lump, lmm, sizeof(*lump)))
-                                GOTO(out_req, rc = -EFAULT);
-                        rc = -EOVERFLOW;
-                }
-        skip_lmm:
+				GOTO(out_req, rc = -EFAULT);
+			rc = -EOVERFLOW;
+		}
+
                 if (cmd == IOC_MDC_GETFILEINFO || cmd == LL_IOC_MDC_GETINFO) {
 			struct lov_user_mds_data __user *lmdp;
                         lstat_t st = { 0 };
diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index 2ff71db..1b0dfab 100755
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -13586,6 +13586,20 @@ test_184e() {
 }
 run_test 184e "Recreate layout after stripeless layout swaps"
 
+test_184f() {
+	# Create a file with name longer than sizeof(struct stat) ==
+	# 144 to see if we can get chars from the file name to appear
+	# in the returned striping. Note that 'f' == 0x66.
+	local file=$(for ((i = 0; i < 200; i++)); do echo -n f; done)
+
+	mkdir -p $DIR/$tdir
+	mcreate $DIR/$tdir/$file
+	if lfs find --stripe-count 0x6666 $DIR/$tdir | grep $file; then
+		error "IOC_MDC_GETFILEINFO returned garbage striping"
+	fi
+}
+run_test 184f "IOC_MDC_GETFILEINFO for files with long names but no striping"
+
 test_185() { # LU-2441
 	# LU-3553 - no volatile file support in old servers
 	[[ $(lustre_version_code $SINGLEMDS) -ge $(version_code 2.3.60) ]] ||