Pull vfs fixes from Al Viro:
"Assorted fixes all over the place.
The iov_iter one is this cycle regression (splice from UDP triggering
WARN_ON()), the rest is older"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs: Use d_instantiate() rather than d_add() and don't d_drop()
afs: Fix missing net error handling
afs: Fix validation/callback interaction
iov_iter: teach csum_and_copy_to_iter() to handle pipe-backed ones
exportfs: do not read dentry after free
exportfs: fix 'passing zero to ERR_PTR()' warning
aio: fix failure to put the file pointer
sysv: return 'err' instead of 0 in __sysv_write_inode