From 106bc79843c3c6f4f00753d1f46e54e815f99377 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 11 Dec 2019 08:06:08 +0000 Subject: [PATCH] afs: Fix missing cell comparison in afs_test_super() 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 Signed-off-by: David Howells Reviewed-by: Marc Dionne Tested-by: Jonathan Billings cc: Todd DeSantis --- fs/afs/super.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/afs/super.c b/fs/afs/super.c index d9a6036b70b9..7f8a9b3137bf 100644 --- a/fs/afs/super.c +++ b/fs/afs/super.c @@ -404,6 +404,7 @@ static int afs_test_super(struct super_block *sb, struct fs_context *fc) return (as->net_ns == fc->net_ns && as->volume && as->volume->vid == ctx->volume->vid && + as->cell == ctx->cell && !as->dyn_root); } -- 2.30.2