| Message ID | 20181109090251.14145-2-cperl@janestreet.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix incorrect sharing of AUTH_SYS and AUTH_GSS_KRB5 data structures | expand |
diff --git a/fs/nfs/super.c b/fs/nfs/super.c index ac4b2f005778..5ef2c71348bd 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -2409,8 +2409,7 @@ static int nfs_compare_mount_options(const struct super_block *s, const struct n goto Ebusy; if (a->acdirmax != b->acdirmax) goto Ebusy; - if (b->auth_info.flavor_len > 0 && - clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) + if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) goto Ebusy; return 1; Ebusy:
This patch removes the check from nfs_compare_mount_options to see if a `sec' option was passed for the current mount before comparing auth flavors and instead just always compares auth flavors. Consider the following scenario: You have a server with the address 192.168.1.1 and two exports /export/a and /export/b. The first export supports `sys' and `krb5' security, the second just `sys'. Assume you start with no mounts from the server. The following results in EIOs being returned as the kernel nfs client incorrectly thinks it can share the underlying `struct nfs_server's: $ mkdir /tmp/{a,b} $ sudo mount -t nfs -o vers=3,sec=krb5 192.168.1.1:/export/a /tmp/a $ sudo mount -t nfs -o vers=3 192.168.1.1:/export/b /tmp/b $ df >/dev/null df: ‘/tmp/b’: Input/output error --- fs/nfs/super.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)