From: Li Dongyang <dongyangli@ddn.com>
Date: Tue, 16 Jul 2019 07:01:01 +0000 (-0700)
Subject: LU-12331 llite: create obd_device with usercopy whitelist
X-Git-Tag: 2.12.3-RC1~114
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=c8cf8521f517842febbab24e0b20a4b88e615416;p=fs%2Flustre-release.git

LU-12331 llite: create obd_device with usercopy whitelist

Since kernel 4.16 hardened usercopy has been added,
whitelist the struct obd_device to silence the warning.

 Bad or missing usercopy whitelist? Kernel memory exposure attempt
 detected from SLUB object 'll_obd_dev_cache' (offset 1256, size 40)!
 WARNING: CPU: 1 PID: 17534 at mm/usercopy.c:83 usercopy_warn+0x7d/0xa0
 Call Trace:
   __check_object_size+0xfa/0x181
   lmv_iocontrol+0x1146/0x1880 [lmv]
   ll_obd_statfs+0x356/0x860 [lustre]
   ll_dir_ioctl+0x1e37/0x6760 [lustre]
   do_vfs_ioctl+0xa4/0x630

Linux-commit: 8eb8284b412906181357c2b0110d879d5af95e52

This patch is back-ported from the following one:
Lustre-commit: 7f77996b1c4ac3a874a1f9e016e8b0e3cfee6992
Lustre-change: https://review.whamcloud.com/34946

Test-Parameters: trivial
Signed-off-by: Li Dongyang <dongyangli@ddn.com>
Change-Id: Ie863e8a5e2cebd3fd716e7ccc4e0491f83f6fabc
Reviewed-on: https://review.whamcloud.com/35528
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Li Xi <lixi@ddn.com>
---

diff --git a/lustre/include/lustre_compat.h b/lustre/include/lustre_compat.h
index 862c1c7..ae99a9e 100644
--- a/lustre/include/lustre_compat.h
+++ b/lustre/include/lustre_compat.h
@@ -42,6 +42,7 @@
 #include <linux/xattr.h>
 #include <linux/workqueue.h>
 #include <linux/blkdev.h>
+#include <linux/slab.h>
 
 #include <libcfs/linux/linux-fs.h>
 #include <lustre_patchless_compat.h>
@@ -787,4 +788,10 @@ static inline bool bdev_integrity_enabled(struct block_device *bdev, int rw)
 #define xa_unlock_irq(lockp) spin_unlock_irq(lockp)
 #endif
 
+#ifndef KMEM_CACHE_USERCOPY
+#define kmem_cache_create_usercopy(name, size, align, flags, useroffset, \
+				   usersize, ctor)			 \
+	kmem_cache_create(name, size, align, flags, ctor)
+#endif
+
 #endif /* _LUSTRE_COMPAT_H */
diff --git a/lustre/obdclass/genops.c b/lustre/obdclass/genops.c
index 9c71703..5a3802d 100644
--- a/lustre/obdclass/genops.c
+++ b/lustre/obdclass/genops.c
@@ -910,9 +910,9 @@ int obd_init_caches(void)
 	ENTRY;
 
 	LASSERT(obd_device_cachep == NULL);
-	obd_device_cachep = kmem_cache_create("ll_obd_dev_cache",
-					      sizeof(struct obd_device),
-					      0, 0, NULL);
+	obd_device_cachep = kmem_cache_create_usercopy("ll_obd_dev_cache",
+				sizeof(struct obd_device),
+				0, 0, 0, sizeof(struct obd_device), NULL);
 	if (!obd_device_cachep)
 		GOTO(out, rc = -ENOMEM);