Propagate an error (EFBIG) to userspace if the physical block is too large to 
return in a 32bit int instead of truncating it.

Signed-off-by: Mike Waychison <[EMAIL PROTECTED]>

 fs/ioctl.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

Index: linux-2.6.23/fs/ioctl.c
===================================================================
--- linux-2.6.23.orig/fs/ioctl.c        2007-10-26 15:26:10.000000000 -0700
+++ linux-2.6.23/fs/ioctl.c     2007-10-26 16:16:28.000000000 -0700
@@ -52,6 +52,7 @@ static int file_ioctl(struct file *filp,
                case FIBMAP:
                {
                        struct address_space *mapping = filp->f_mapping;
+                       sector_t phys_block;
                        int res;
                        /* do we support this mess? */
                        if (!mapping->a_ops->bmap)
@@ -64,8 +65,15 @@ static int file_ioctl(struct file *filp,
                                return -EINVAL;
 
                        lock_kernel();
-                       res = mapping->a_ops->bmap(mapping, block);
+                       phys_block = mapping->a_ops->bmap(mapping, block);
                        unlock_kernel();
+
+                       /* Make sure that the return value fits in the
+                        * user's buffer. */
+                       if ((u32)phys_block < phys_block)
+                               return -EFBIG;
+
+                       res = phys_block;
                        return put_user(res, p);
                }
                case FIGETBSZ:

--
-
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