[lustre-devel] [PATCH 37/41] staging: lustre: lov: copy_to_user uses wrong casting

James Simmons jsimmons at infradead.org
Sun Oct 2 19:28:33 PDT 2016

With certain version of gcc lov_obd.c failes to compile
with the following warning.

In function copy_to_user,
inlined from lov_iocontrol at
./arch/x86/include/asm/uaccess.h:735: error: call to
__copy_to_user_overflow declared with attribute warning:
copy_to_user() buffer size is not probably correct

In lov_iocontrol the data was being casted to int instead
of the required unsigned long. This patch changes the cast
to what is needed for copy_to_user.

Signed-off-by: James Simmons <uja.ornl at yahoo.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6302
Reviewed-on: http://review.whamcloud.com/14613
Reviewed-by: frank zago <fzago at cray.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin at intel.com>
Reviewed-by: John L. Hammond <john.hammond at intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin at intel.com>
Signed-off-by: James Simmons <jsimmons at infradead.org>
 drivers/staging/lustre/lustre/lov/lov_obd.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/lustre/lustre/lov/lov_obd.c b/drivers/staging/lustre/lustre/lov/lov_obd.c
index 473071c..18cb92d 100644
--- a/drivers/staging/lustre/lustre/lov/lov_obd.c
+++ b/drivers/staging/lustre/lustre/lov/lov_obd.c
@@ -1085,8 +1085,8 @@ static int lov_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
 		/* copy UUID */
 		if (copy_to_user(data->ioc_pbuf2, obd2cli_tgt(osc_obd),
-				 min((int)data->ioc_plen2,
-				     (int)sizeof(struct obd_uuid))))
+				 min_t(unsigned long, data->ioc_plen2,
+				       sizeof(struct obd_uuid))))
 			return -EFAULT;
 		memcpy(&flags, data->ioc_inlbuf1, sizeof(__u32));
@@ -1099,8 +1099,8 @@ static int lov_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
 		if (rc)
 			return rc;
 		if (copy_to_user(data->ioc_pbuf1, &stat_buf,
-				 min((int)data->ioc_plen1,
-				     (int)sizeof(stat_buf))))
+				 min_t(unsigned long, data->ioc_plen1,
+				       sizeof(stat_buf))))
 			return -EFAULT;

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