nfs + msdosfs = crashes & panics

[Matthew Dillon]

:On Tue, 13 Apr 2004 17:39:24 -0700
:Jeffrey Hsu <hsu at xxxxxxxxxxx> wrote:
:
:> You're probably indirecting though a non-existent proc-related
:> structure. The protocol threads don't have a proc structure associated
:> with them.  Before, there were a bunch of places which incorrectly
:> used curproc to check things like credentials.   All the places
:> are going to core dump now.  I've fixed a bunch of places which
:> incorrectly used curthread, but there are still some left.
:
:I was starting to wonder if it had something to do with the struct
:ucred... this would make sense... esp. considering it's an MS-DOS
:filesystem... i.e., it carries no user info on files.
:
:FWIW, it's the same behaviour with -mapall=catseye as without (catseye
:is the user who owns the /c directory, and mount_msdos treats that user
:as the owner of all files under it, when it's mounted.)
:
:-Chris

    Yup, that was it.   msdosfs_write() was getting proc from 
    uio->uio_td->td_proc, but uio_td can be NULL.  In this case I just
    conditionalized it, the proc is being used to do filesize resource
    limit checks and I think we can safely say that we don't really care
    about that for msdosfs which stores no user cred info anyways, and
    doubly so when accessed from an NFS server.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>