From: Jason Gunthorpe <jgg@mellanox.com>
Date: Thu, 9 Aug 2018 16:19:35 +0000 (+0300)
Subject: IB/uverbs: Fix reading of 32 bit flags
X-Git-Tag: v4.19~309^2~30
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=922983c2a1a2f679cd576eb7162f413c15a4e979;p=platform%2Fkernel%2Flinux-rpi.git

IB/uverbs: Fix reading of 32 bit flags

This is missing a zeroing of the high bits of flags, and is also not
correct for big endian machines. Properly zero extend the 32 bit flags
into the 64 bit stack variable.

Reported-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Fixes: bccd06223f21 ("IB/uverbs: Add UVERBS_ATTR_FLAGS_IN to the specs language")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
---

diff --git a/drivers/infiniband/core/uverbs_ioctl.c b/drivers/infiniband/core/uverbs_ioctl.c
index f0655a8..23ff698 100644
--- a/drivers/infiniband/core/uverbs_ioctl.c
+++ b/drivers/infiniband/core/uverbs_ioctl.c
@@ -535,7 +535,7 @@ int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 	if (attr->ptr_attr.len == 8)
 		flags = attr->ptr_attr.data;
 	else if (attr->ptr_attr.len == 4)
-		memcpy(&flags, &attr->ptr_attr.data, 4);
+		flags = *(u32 *)&attr->ptr_attr.data;
 	else
 		return -EINVAL;