| From fc7605bd4b2b19458bb21a57f2cfaeb475140e9a Mon Sep 17 00:00:00 2001 |
| From: David Howells <dhowells@redhat.com> |
| Date: Thu, 26 Mar 2020 15:24:07 +0000 |
| Subject: [PATCH] afs: Fix unpinned address list during probing |
| |
| commit 9efcc4a129363187c9bf15338692f107c5c9b6f0 upstream. |
| |
| When it's probing all of a fileserver's interfaces to find which one is |
| best to use, afs_do_probe_fileserver() takes a lock on the server record |
| and notes the pointer to the address list. |
| |
| It doesn't, however, pin the address list, so as soon as it drops the |
| lock, there's nothing to stop the address list from being freed under |
| us. |
| |
| Fix this by taking a ref on the address list inside the locked section |
| and dropping it at the end of the function. |
| |
| Fixes: 3bf0fb6f33dd ("afs: Probe multiple fileservers simultaneously") |
| Signed-off-by: David Howells <dhowells@redhat.com> |
| Reviewed-by: Marc Dionne <marc.dionne@auristor.com> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c |
| index cfe62b154f68..e1b9ed679045 100644 |
| --- a/fs/afs/fs_probe.c |
| +++ b/fs/afs/fs_probe.c |
| @@ -145,6 +145,7 @@ static int afs_do_probe_fileserver(struct afs_net *net, |
| read_lock(&server->fs_lock); |
| ac.alist = rcu_dereference_protected(server->addresses, |
| lockdep_is_held(&server->fs_lock)); |
| + afs_get_addrlist(ac.alist); |
| read_unlock(&server->fs_lock); |
| |
| atomic_set(&server->probe_outstanding, ac.alist->nr_addrs); |
| @@ -163,6 +164,7 @@ static int afs_do_probe_fileserver(struct afs_net *net, |
| |
| if (!in_progress) |
| afs_fs_probe_done(server); |
| + afs_put_addrlist(ac.alist); |
| return in_progress; |
| } |
| |
| -- |
| 2.7.4 |
| |
