kern/119842: "Bad address" with smbfs inside a jail

[Kirk Strauser]

>Number:         119842
>Category:       kern
>Synopsis:       "Bad address" with smbfs inside a jail
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Jan 20 21:20:03 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Kirk Strauser
>Release:        7.0-PRERELEASE
>Organization:
The Day Companies
>Environment:
FreeBSD jail1.daycos.com 7.0-PRERELEASE FreeBSD 7.0-PRERELEASE #0: Sat Jan 19 11:16:27 CST 2008     root at jail1.daycos.com:/usr/obj/usr/src/sys/JAIL1  i386
>Description:
I have a very new FreeBSD 7 build on a server:

-------------------------
$ uname -a
FreeBSD jail1.daycos.com 7.0-PRERELEASE FreeBSD 7.0-PRERELEASE #0: Sat Jan 19 11:16:27 CST 2008     root at jail1.daycos.com:/usr/obj/usr/src/sys/JAIL1  i386
-------------------------

Its kernel is very close to GENERIC (and I've tried GENERIC with
/etc/make.conf:CPUTYPE unset just to rule it out):

-------------------------
$ cat /usr/src/sys/i386/conf/JAIL1
include                 GENERIC
ident                   JAIL1
options                 PMAP_SHPGPERPROC=301

nooption                SCHED_4BSD
option                  SCHED_ULE

# Don't let Mike accidentally reboot the server
option                  SC_DISABLE_REBOOT       # disable reboot key sequence
-------------------------

I have the same smbfs share mounted in two different places on the system:
once inside the "main" system and once inside a jail.  I'm having a problem
with the jailed version when copying new files:

-------------------------
$ cp /mnt/tiffsrv/vdrive/Scanned/2008/01/20/2008012014450000.tif /tmp/foo
cp: /tmp/foo: Bad address
-------------------------

This only affects new files; that is, ones that have been created since
the filesystem was mounted.  If I unmount/remount the filesystem, that copy
succeeds:

-------------------------
$ cp /mnt/tiffsrv/vdrive/Scanned/2008/01/20/2008012014450000.tif /tmp/foo
$
-------------------------

The fstab entries for those mounts are identical:

-------------------------
$ grep tiffsrv /etc/fstab
//web2 at tiffsrv/vdrive /mnt/tiffsrv/vdrive smbfs rw,noexec 0 0
$ grep tiffsrv /etc/fstab.web2
//web2 at tiffsrv/vdrive /var/jail/web2/mnt/tiffsrv/vdrive smbfs rw,noexec 0 0
-------------------------

>How-To-Repeat:
Mount an smbfs somewhere that a jail can access it.
Inside the jail, create a file inside the smbfs mount.
Inside the same jail, try copy that file to, say, /tmp.
This will randomly, but often (maybe 50% of the time) fail with "Bad address".
>Fix:
unmount and remount the smbfs share.  This is suboptimal in production.

>Release-Note:
>Audit-Trail:
>Unformatted: