[RFC PATCH 25/35] nfsd: take xattr access bits in to account when checking

Frank van der Linden
2019-09-12T17:28:53Z

Since the NFSv4.2 extended attributes extension defines 3 new access
bits for xattr operations, take them in to account when validating
what the client is asking for, and when checking permissions.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
---
fs/nfsd/nfs4proc.c | 10 +++++++++-
fs/nfsd/vfs.c | 12 ++++++++++++
2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 6fc960677644..6ade983dd9b2 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -557,8 +557,16 @@ nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
union nfsd4_op_u *u)
{
struct nfsd4_access *access = &u->access;
+ u32 access_full;

- if (access->ac_req_access & ~NFS3_ACCESS_FULL)
+ access_full = NFS3_ACCESS_FULL;
+#ifdef CONFIG_NFSD_V4_XATTR
+ if (cstate->minorversion >= 2)
+ access_full |= NFS4_ACCESS_XALIST | NFS4_ACCESS_XAREAD |
+ NFS4_ACCESS_XAWRITE;
+#endif
+
+ if (access->ac_req_access & ~access_full)
return nfserr_inval;

access->ac_resp_access = access->ac_req_access;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 99363e7ce044..d76e3041fa8e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -611,6 +611,12 @@ static struct accessmap nfs3_regaccess[] = {
{ NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC },
{ NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE },

+#ifdef CONFIG_NFSD_V4_XATTR
+ { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
+ { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
+ { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
+#endif
+
{ 0, 0 }
};

@@ -621,6 +627,12 @@ static struct accessmap nfs3_diraccess[] = {
{ NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE },
{ NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE },

+#ifdef CONFIG_NFSD_V4_XATTR
+ { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
+ { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
+ { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
+#endif
+
{ 0, 0 }
};

--
2.17.2