diff options
Diffstat (limited to 'fs/nfs/nfs4namespace.c')
-rw-r--r-- | fs/nfs/nfs4namespace.c | 118 |
1 files changed, 89 insertions, 29 deletions
diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index ea38d27b74e6..24e47f3bbd17 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -2,6 +2,7 @@ * linux/fs/nfs/nfs4namespace.c * * Copyright (C) 2005 Trond Myklebust <Trond.Myklebust@netapp.com> + * - Modified by David Howells <dhowells@redhat.com> * * NFSv4 namespace */ @@ -23,7 +24,7 @@ /* * Check if fs_root is valid */ -static inline char *nfs4_pathname_string(struct nfs4_pathname *pathname, +static inline char *nfs4_pathname_string(const struct nfs4_pathname *pathname, char *buffer, ssize_t buflen) { char *end = buffer + buflen; @@ -34,7 +35,7 @@ static inline char *nfs4_pathname_string(struct nfs4_pathname *pathname, n = pathname->ncomponents; while (--n >= 0) { - struct nfs4_string *component = &pathname->components[n]; + const struct nfs4_string *component = &pathname->components[n]; buflen -= component->len + 1; if (buflen < 0) goto Elong; @@ -47,6 +48,68 @@ Elong: return ERR_PTR(-ENAMETOOLONG); } +/* + * Determine the mount path as a string + */ +static char *nfs4_path(const struct vfsmount *mnt_parent, + const struct dentry *dentry, + char *buffer, ssize_t buflen) +{ + const char *srvpath; + + srvpath = strchr(mnt_parent->mnt_devname, ':'); + if (srvpath) + srvpath++; + else + srvpath = mnt_parent->mnt_devname; + + return nfs_path(srvpath, mnt_parent->mnt_root, dentry, buffer, buflen); +} + +/* + * Check that fs_locations::fs_root [RFC3530 6.3] is a prefix for what we + * believe to be the server path to this dentry + */ +static int nfs4_validate_fspath(const struct vfsmount *mnt_parent, + const struct dentry *dentry, + const struct nfs4_fs_locations *locations, + char *page, char *page2) +{ + const char *path, *fs_path; + + path = nfs4_path(mnt_parent, dentry, page, PAGE_SIZE); + if (IS_ERR(path)) + return PTR_ERR(path); + + fs_path = nfs4_pathname_string(&locations->fs_path, page2, PAGE_SIZE); + if (IS_ERR(fs_path)) + return PTR_ERR(fs_path); + + if (strncmp(path, fs_path, strlen(fs_path)) != 0) { + dprintk("%s: path %s does not begin with fsroot %s\n", + __FUNCTION__, path, fs_path); + return -ENOENT; + } + + return 0; +} + +/* + * Check if the string represents a "valid" IPv4 address + */ +static inline int valid_ipaddr4(const char *buf) +{ + int rc, count, in[4]; + + rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); + if (rc != 4) + return -EINVAL; + for (count = 0; count < 4; count++) { + if (in[count] > 255) + return -EINVAL; + } + return 0; +} /** * nfs_follow_referral - set up mountpoint when hitting a referral on moved error @@ -60,7 +123,7 @@ Elong: */ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, const struct dentry *dentry, - struct nfs4_fs_locations *locations) + const struct nfs4_fs_locations *locations) { struct vfsmount *mnt = ERR_PTR(-ENOENT); struct nfs_clone_mount mountdata = { @@ -68,10 +131,9 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, .dentry = dentry, .authflavor = NFS_SB(mnt_parent->mnt_sb)->client->cl_auth->au_flavor, }; - char *page, *page2; - char *path, *fs_path; + char *page = NULL, *page2 = NULL; char *devname; - int loc, s; + int loc, s, error; if (locations == NULL || locations->nlocations <= 0) goto out; @@ -79,36 +141,30 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, dprintk("%s: referral at %s/%s\n", __FUNCTION__, dentry->d_parent->d_name.name, dentry->d_name.name); - /* Ensure fs path is a prefix of current dentry path */ page = (char *) __get_free_page(GFP_USER); - if (page == NULL) + if (!page) goto out; + page2 = (char *) __get_free_page(GFP_USER); - if (page2 == NULL) + if (!page2) goto out; - path = nfs4_path(dentry, page, PAGE_SIZE); - if (IS_ERR(path)) - goto out_free; - - fs_path = nfs4_pathname_string(&locations->fs_path, page2, PAGE_SIZE); - if (IS_ERR(fs_path)) - goto out_free; - - if (strncmp(path, fs_path, strlen(fs_path)) != 0) { - dprintk("%s: path %s does not begin with fsroot %s\n", __FUNCTION__, path, fs_path); - goto out_free; + /* Ensure fs path is a prefix of current dentry path */ + error = nfs4_validate_fspath(mnt_parent, dentry, locations, page, page2); + if (error < 0) { + mnt = ERR_PTR(error); + goto out; } devname = nfs_devname(mnt_parent, dentry, page, PAGE_SIZE); if (IS_ERR(devname)) { mnt = (struct vfsmount *)devname; - goto out_free; + goto out; } loc = 0; while (loc < locations->nlocations && IS_ERR(mnt)) { - struct nfs4_fs_location *location = &locations->locations[loc]; + const struct nfs4_fs_location *location = &locations->locations[loc]; char *mnt_path; if (location == NULL || location->nservers <= 0 || @@ -140,7 +196,7 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, addr.sin_port = htons(NFS_PORT); mountdata.addr = &addr; - mnt = vfs_kern_mount(&nfs_referral_nfs4_fs_type, 0, devname, &mountdata); + mnt = vfs_kern_mount(&nfs4_referral_fs_type, 0, devname, &mountdata); if (!IS_ERR(mnt)) { break; } @@ -149,10 +205,9 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, loc++; } -out_free: - free_page((unsigned long)page); - free_page((unsigned long)page2); out: + free_page((unsigned long) page); + free_page((unsigned long) page2); dprintk("%s: done\n", __FUNCTION__); return mnt; } @@ -165,7 +220,7 @@ out: */ struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry) { - struct vfsmount *mnt = ERR_PTR(-ENOENT); + struct vfsmount *mnt = ERR_PTR(-ENOMEM); struct dentry *parent; struct nfs4_fs_locations *fs_locations = NULL; struct page *page; @@ -183,11 +238,16 @@ struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentr goto out_free; /* Get locations */ + mnt = ERR_PTR(-ENOENT); + parent = dget_parent(dentry); - dprintk("%s: getting locations for %s/%s\n", __FUNCTION__, parent->d_name.name, dentry->d_name.name); + dprintk("%s: getting locations for %s/%s\n", + __FUNCTION__, parent->d_name.name, dentry->d_name.name); + err = nfs4_proc_fs_locations(parent->d_inode, dentry, fs_locations, page); dput(parent); - if (err != 0 || fs_locations->nlocations <= 0 || + if (err != 0 || + fs_locations->nlocations <= 0 || fs_locations->fs_path.ncomponents <= 0) goto out_free; |