[SCSI] compat_ioct: fix bsg SG_IO

bsg's SG_IO doesn't work on 32-bit userspace and 64-bit kernelspace.

The problem is that both sg and bsg drivers use SG_IO
ioctl. sg_ioctl_trans() does 32/64-bit conversion even against bsg
header. It messes up bsg header. bsg driver gets garbage.

This patch fixes sg_ioctl_trans to handle only sg header (struct
sg_io_hdr).

Reported-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index c5c45de1a2ee..7cbbc7ab4b50 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -301,6 +301,12 @@ static int sg_ioctl_trans(unsigned int fd, unsigned int cmd,
         u32 data;
         void __user *dxferp;
         int err;
+        int interface_id;
+
+        if (get_user(interface_id, &sgio32->interface_id))
+                return -EFAULT;
+        if (interface_id != 'S')
+                return sys_ioctl(fd, cmd, (unsigned long)sgio32);
 
         if (get_user(iovec_count, &sgio32->iovec_count))
                 return -EFAULT;