Add full support for the NFSv3 permissions checking. Ensures that we
work properly with NFSv3 servers that do uid/gid mapping and/or have
support for ACLs.
Permissions are cached in the struct nfs_inode in order to reduce the
number of RPC calls. The cache timeout period is given by the ordinary
attribute timeout.
Cheers,
Trond
diff -u --recursive --new-file linux-2.5.28-cto2/fs/nfs/dir.c linux-2.5.28-access/fs/nfs/dir.c
--- linux-2.5.28-cto2/fs/nfs/dir.c Fri Jul 26 21:15:30 2002
+++ linux-2.5.28-access/fs/nfs/dir.c Fri Jul 26 21:15:42 2002
@@ -1080,38 +1080,70 @@
int
nfs_permission(struct inode *inode, int mask)
{
- int error = vfs_permission(inode, mask);
-
- if (!NFS_PROTO(inode)->access)
- goto out;
-
- if (error == -EROFS)
- goto out;
-
- /*
- * Trust UNIX mode bits except:
- *
- * 1) When override capabilities may have been invoked
- * 2) When root squashing may be involved
- * 3) When ACLs may overturn a negative answer */
- if (!capable(CAP_DAC_OVERRIDE) && !capable(CAP_DAC_READ_SEARCH)
- && (current->fsuid != 0) && (current->fsgid != 0)
- && error != -EACCES)
- goto out;
+ struct nfs_access_cache *cache = &NFS_I(inode)->cache_access;
+ struct rpc_cred *cred;
+ int mode = inode->i_mode;
+ int res;
+
+ if (mask & MAY_WRITE) {
+ /*
+ *
+ * Nobody gets write access to a read-only fs.
+ *
+ */
+ if (IS_RDONLY(inode) &&
+ (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
+ return -EROFS;
+
+ /*
+ *
+ * Nobody gets write access to an immutable file.
+ *
+ */
+ if (IS_IMMUTABLE(inode))
+ return -EACCES;
+ }
lock_kernel();
- error = NFS_PROTO(inode)->access(inode, mask, 0);
-
- if (error == -EACCES && NFS_CLIENT(inode)->cl_droppriv &&
- current->uid != 0 && current->gid != 0 &&
- (current->fsuid != current->uid || current->fsgid != current->gid))
- error = NFS_PROTO(inode)->access(inode, mask, 1);
+ if (!NFS_PROTO(inode)->access)
+ goto out_notsup;
+ cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0);
+ if (cache->cred == cred
+ && time_before(jiffies, cache->jiffies + NFS_ATTRTIMEO(inode))) {
+ if (!(res = cache->err)) {
+ /* Is the mask a subset of an accepted mask? */
+ if ((cache->mask & mask) == mask)
+ goto out;
+ } else {
+ /* ...or is it a superset of a rejected mask? */
+ if ((cache->mask & mask) == cache->mask)
+ goto out;
+ }
+ }
+
+ res = NFS_PROTO(inode)->access(inode, cred, mask);
+ if (!res || res == -EACCES)
+ goto add_cache;
+out:
+ put_rpccred(cred);
unlock_kernel();
-
- out:
- return error;
+ return res;
+out_notsup:
+ nfs_revalidate_inode(NFS_SERVER(inode), inode);
+ res = vfs_permission(inode, mask);
+ unlock_kernel();
+ return res;
+add_cache:
+ cache->jiffies = jiffies;
+ if (cache->cred)
+ put_rpccred(cache->cred);
+ cache->cred = cred;
+ cache->mask = mask;
+ cache->err = res;
+ unlock_kernel();
+ return res;
}
/*
diff -u --recursive --new-file linux-2.5.28-cto2/fs/nfs/inode.c linux-2.5.28-access/fs/nfs/inode.c
--- linux-2.5.28-cto2/fs/nfs/inode.c Fri Jul 26 21:04:48 2002
+++ linux-2.5.28-access/fs/nfs/inode.c Fri Jul 26 21:09:24 2002
@@ -125,10 +125,14 @@
static void
nfs_clear_inode(struct inode *inode)
{
- struct rpc_cred *cred = NFS_I(inode)->mm_cred;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct rpc_cred *cred = nfsi->mm_cred;
if (cred)
put_rpccred(cred);
+ cred = nfsi->cache_access.cred;
+ if (cred)
+ put_rpccred(cred);
}
void
@@ -722,6 +726,7 @@
NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
memset(NFS_COOKIEVERF(inode), 0, sizeof(NFS_COOKIEVERF(inode)));
+ NFS_I(inode)->cache_access.cred = NULL;
unlock_new_inode(inode);
} else
@@ -1085,6 +1090,16 @@
NFS_CACHE_ISIZE(inode) = new_size;
inode->i_size = new_isize;
+ if (inode->i_mode != fattr->mode ||
+ inode->i_uid != fattr->uid ||
+ inode->i_gid != fattr->gid) {
+ struct rpc_cred **cred = &NFS_I(inode)->cache_access.cred;
+ if (*cred) {
+ put_rpccred(*cred);
+ *cred = NULL;
+ }
+ }
+
inode->i_mode = fattr->mode;
inode->i_nlink = fattr->nlink;
inode->i_uid = fattr->uid;
diff -u --recursive --new-file linux-2.5.28-cto2/fs/nfs/nfs3proc.c linux-2.5.28-access/fs/nfs/nfs3proc.c
--- linux-2.5.28-cto2/fs/nfs/nfs3proc.c Thu May 23 17:09:24 2002
+++ linux-2.5.28-access/fs/nfs/nfs3proc.c Fri Jul 26 21:53:34 2002
@@ -133,16 +133,22 @@
}
static int
-nfs3_proc_access(struct inode *inode, int mode, int ruid)
+nfs3_proc_access(struct inode *inode, struct rpc_cred *cred, int mode)
{
struct nfs_fattr fattr;
struct nfs3_accessargs arg = {
- fh: NFS_FH(inode),
+ .fh = NFS_FH(inode),
};
struct nfs3_accessres res = {
- fattr: &fattr,
+ .fattr = &fattr,
};
- int status, flags;
+ struct rpc_message msg = {
+ .rpc_proc = NFS3PROC_ACCESS,
+ .rpc_argp = &arg,
+ .rpc_resp = &res,
+ .rpc_cred = cred
+ };
+ int status;
dprintk("NFS call access\n");
fattr.valid = 0;
@@ -160,8 +166,7 @@
if (mode & MAY_EXEC)
arg.access |= NFS3_ACCESS_EXECUTE;
}
- flags = (ruid) ? RPC_CALL_REALUID : 0;
- status = rpc_call(NFS_CLIENT(inode), NFS3PROC_ACCESS, &arg, &res, flags);
+ status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
nfs_refresh_inode(inode, &fattr);
dprintk("NFS reply access\n");
diff -u --recursive --new-file linux-2.5.28-cto2/include/linux/nfs_fs.h linux-2.5.28-access/include/linux/nfs_fs.h
--- linux-2.5.28-cto2/include/linux/nfs_fs.h Sat Jun 1 03:18:09 2002
+++ linux-2.5.28-access/include/linux/nfs_fs.h Fri Jul 26 21:05:37 2002
@@ -90,6 +90,16 @@
#ifdef __KERNEL__
/*
+ * NFSv3 Access mode cache
+ */
+struct nfs_access_cache {
+ unsigned long jiffies;
+ struct rpc_cred * cred;
+ int mask;
+ int err;
+};
+
+/*
* nfs fs inode data in memory
*/
struct nfs_inode {
@@ -138,6 +148,8 @@
*/
unsigned long cache_mtime_jiffies;
+ struct nfs_access_cache cache_access;
+
/*
* This is the cookie verifier used for NFSv3 readdir
* operations
diff -u --recursive --new-file linux-2.5.28-cto2/include/linux/nfs_xdr.h linux-2.5.28-access/include/linux/nfs_xdr.h
--- linux-2.5.28-cto2/include/linux/nfs_xdr.h Mon Jul 15 19:03:21 2002
+++ linux-2.5.28-access/include/linux/nfs_xdr.h Fri Jul 26 14:35:23 2002
@@ -300,7 +300,7 @@
struct iattr *);
int (*lookup) (struct inode *, struct qstr *,
struct nfs_fh *, struct nfs_fattr *);
- int (*access) (struct inode *, int , int);
+ int (*access) (struct inode *, struct rpc_cred *, int);
int (*readlink)(struct inode *, struct page *);
int (*read) (struct inode *, struct rpc_cred *,
struct nfs_fattr *,
-
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This archive was generated by hypermail 2b29 : Tue Jul 30 2002 - 14:00:25 EST