[PATCH 3.10 23/64] [media] v4l2-compat-ioctl32: fix alignment for ARM64

From: Greg Kroah-Hartman
Date: Sun Feb 14 2016 - 18:39:41 EST


3.10-stable review patch. If anyone has any objections, please let me know.

------------------

From: Andrzej Hajda <a.hajda@xxxxxxxxxxx>

commit 655e9780ab913a3a06d4a164d55e3b755524186d upstream.

Alignment/padding rules on AMD64 and ARM64 differs. To allow properly match
compatible ioctls on ARM64 kernels without breaking AMD64 some fields
should be aligned using compat_s64 type and in one case struct should be
unpacked.

Signed-off-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
[hans.verkuil@xxxxxxxxx: use compat_u64 instead of compat_s64 in v4l2_input32]
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx>

---
drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -264,7 +264,7 @@ static int put_v4l2_create32(struct v4l2

struct v4l2_standard32 {
__u32 index;
- __u32 id[2]; /* __u64 would get the alignment wrong */
+ compat_u64 id;
__u8 name[24];
struct v4l2_fract frameperiod; /* Frames, not fields */
__u32 framelines;
@@ -284,7 +284,7 @@ static int put_v4l2_standard32(struct v4
{
if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_standard32)) ||
put_user(kp->index, &up->index) ||
- copy_to_user(up->id, &kp->id, sizeof(__u64)) ||
+ put_user(kp->id, &up->id) ||
copy_to_user(up->name, kp->name, 24) ||
copy_to_user(&up->frameperiod, &kp->frameperiod, sizeof(kp->frameperiod)) ||
put_user(kp->framelines, &up->framelines) ||
@@ -576,10 +576,10 @@ struct v4l2_input32 {
__u32 type; /* Type of input */
__u32 audioset; /* Associated audios (bitfield) */
__u32 tuner; /* Associated tuner */
- v4l2_std_id std;
+ compat_u64 std;
__u32 status;
__u32 reserved[4];
-} __attribute__ ((packed));
+};

/* The 64-bit v4l2_input struct has extra padding at the end of the struct.
Otherwise it is identical to the 32-bit version. */
@@ -719,6 +719,7 @@ static int put_v4l2_ext_controls32(struc
struct v4l2_event32 {
__u32 type;
union {
+ compat_s64 value64;
__u8 data[64];
} u;
__u32 pending;