From: David Howells dhowells@redhat.com
commit 106bc79843c3c6f4f00753d1f46e54e815f99377 upstream.
Fix missing cell comparison in afs_test_super(). Without this, any pair volumes that have the same volume ID will share a superblock, no matter the cell, unless they're in different network namespaces.
Normally, most users will only deal with a single cell and so they won't see this. Even if they do look into a second cell, they won't see a problem unless they happen to hit a volume with the same ID as one they've already got mounted.
Before the patch:
# ls /afs/grand.central.org/archive linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/ # ls /afs/kth.se/ linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/ # cat /proc/mounts | grep afs none /afs afs rw,relatime,dyn,autocell 0 0 #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0 #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0 #grand.central.org:root.archive /afs/kth.se afs ro,relatime 0 0
After the patch:
# ls /afs/grand.central.org/archive linuxdev/ mailman/ moin/ mysql/ pipermail/ stage/ twiki/ # ls /afs/kth.se/ admin/ common/ install/ OldFiles/ service/ system/ bakrestores/ home/ misc/ pkg/ src/ wsadmin/ # cat /proc/mounts | grep afs none /afs afs rw,relatime,dyn,autocell 0 0 #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0 #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0 #kth.se:root.cell /afs/kth.se afs ro,relatime 0 0
Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Carsten Jacobi jacobi@de.ibm.com Signed-off-by: David Howells dhowells@redhat.com Reviewed-by: Marc Dionne marc.dionne@auristor.com Tested-by: Jonathan Billings jsbillings@jsbillings.org cc: Todd DeSantis atd@us.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/afs/super.c | 1 + 1 file changed, 1 insertion(+)
--- a/fs/afs/super.c +++ b/fs/afs/super.c @@ -356,6 +356,7 @@ static int afs_test_super(struct super_b return (as->net_ns == as1->net_ns && as->volume && as->volume->vid == as1->volume->vid && + as->cell == as1->cell && !as->dyn_root); }