[PATCH 10/29] staging: lustre: libcfs: test if userland data is to small

[James Simmons]

From: Liang Zhen <liang.zhen@xxxxxxxxx>

Ensure that user land data is at least the smallest size.

Signed-off-by: Liang Zhen <liang.zhen@xxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5435
Reviewed-on: http://review.whamcloud.com/11313
Reviewed-by: Bobi Jam <bobijam@xxxxxxxxx>
Reviewed-by: Johann Lombardi <johann.lombardi@xxxxxxxxx>
Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
---
 .../lustre/lnet/libcfs/linux/linux-module.c        |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/lustre/lnet/libcfs/linux/linux-module.c b/drivers/staging/lustre/lnet/libcfs/linux/linux-module.c
index 35e2fcf..ae05895 100644
--- a/drivers/staging/lustre/lnet/libcfs/linux/linux-module.c
+++ b/drivers/staging/lustre/lnet/libcfs/linux/linux-module.c
@@ -73,6 +73,11 @@ int libcfs_ioctl_getdata(struct libcfs_ioctl_hdr **hdr_pp,
 		return -EINVAL;
 	}
 
+	if (hdr.ioc_len < sizeof(struct libcfs_ioctl_data)) {
+		CERROR("libcfs ioctl: user buffer too small for ioctl\n");
+		return -EINVAL;
+	}
+
 	if (hdr.ioc_len > LIBCFS_IOC_DATA_MAX) {
 		CERROR("libcfs ioctl: user buffer is too large %d/%d\n",
 		       hdr.ioc_len, LIBCFS_IOC_DATA_MAX);
-- 
1.7.1