X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=fs%2Fnfsd%2Fnfsfh.c;h=d0d8a217a3ea903ce45fa6be1112733c2a12a534;hp=cd25d91895a19fc0906b3e5b1891bed123cff15b;hb=0a3adadee42f2865bb867b8c5f4955b7def9baad;hpb=04716e6621ff4abb422d64ba7b48718f52716a3e diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index cd25d91..d0d8a21 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -22,14 +22,12 @@ #include #include #include +#include "vfs.h" #include "auth.h" #define NFSDDBG_FACILITY NFSDDBG_FH -static int nfsd_nr_verified; -static int nfsd_nr_put; - /* * our acceptability function. * if NOSUBTREECHECK, accept anything @@ -186,9 +184,14 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) * access control settings being in effect, we cannot * fix that case easily. */ - current->cap_effective = - cap_raise_nfsd_set(current->cap_effective, - current->cap_permitted); + struct cred *new = prepare_creds(); + if (!new) + return nfserrno(-ENOMEM); + new->cap_effective = + cap_raise_nfsd_set(new->cap_effective, + new->cap_permitted); + put_cred(override_creds(new)); + put_cred(new); } else { error = nfsd_setuser_and_check_port(rqstp, exp); if (error) @@ -246,21 +249,38 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) fhp->fh_dentry = dentry; fhp->fh_export = exp; - nfsd_nr_verified++; return 0; out: exp_put(exp); return error; } -/* - * Perform sanity checks on the dentry in a client's file handle. +/** + * fh_verify - filehandle lookup and access checking + * @rqstp: pointer to current rpc request + * @fhp: filehandle to be verified + * @type: expected type of object pointed to by filehandle + * @access: type of access needed to object + * + * Look up a dentry from the on-the-wire filehandle, check the client's + * access to the export, and set the current task's credentials. * - * Note that the file handle dentry may need to be freed even after - * an error return. + * Regardless of success or failure of fh_verify(), fh_put() should be + * called on @fhp when the caller is finished with the filehandle. * - * This is only called at the start of an nfsproc call, so fhp points to - * a svc_fh which is all 0 except for the over-the-wire file handle. + * fh_verify() may be called multiple times on a given filehandle, for + * example, when processing an NFSv4 compound. The first call will look + * up a dentry using the on-the-wire filehandle. Subsequent calls will + * skip the lookup and just perform the other checks and possibly change + * the current task's credentials. + * + * @type specifies the type of object expected using one of the S_IF* + * constants defined in include/linux/stat.h. The caller may use zero + * to indicate that it doesn't care, or a negative integer to indicate + * that it expects something not of the given type. + * + * @access is formed from the NFSD_MAY_* constants defined in + * include/linux/nfsd/nfsd.h. */ __be32 fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) @@ -378,44 +398,51 @@ static inline void _fh_update_old(struct dentry *dentry, fh->ofh_dirino = 0; } -__be32 -fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, - struct svc_fh *ref_fh) +static bool is_root_export(struct svc_export *exp) { - /* ref_fh is a reference file handle. - * if it is non-null and for the same filesystem, then we should compose - * a filehandle which is of the same version, where possible. - * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca - * Then create a 32byte filehandle using nfs_fhbase_old - * - */ + return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root; +} - u8 version; - u8 fsid_type = 0; - struct inode * inode = dentry->d_inode; - struct dentry *parent = dentry->d_parent; - __u32 *datap; - dev_t ex_dev = exp->ex_path.dentry->d_inode->i_sb->s_dev; - int root_export = (exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root); +static struct super_block *exp_sb(struct svc_export *exp) +{ + return exp->ex_path.dentry->d_inode->i_sb; +} - dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", - MAJOR(ex_dev), MINOR(ex_dev), - (long) exp->ex_path.dentry->d_inode->i_ino, - parent->d_name.name, dentry->d_name.name, - (inode ? inode->i_ino : 0)); +static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp) +{ + switch (fsid_type) { + case FSID_DEV: + if (!old_valid_dev(exp_sb(exp)->s_dev)) + return 0; + /* FALL THROUGH */ + case FSID_MAJOR_MINOR: + case FSID_ENCODE_DEV: + return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV; + case FSID_NUM: + return exp->ex_flags & NFSEXP_FSID; + case FSID_UUID8: + case FSID_UUID16: + if (!is_root_export(exp)) + return 0; + /* fall through */ + case FSID_UUID4_INUM: + case FSID_UUID16_INUM: + return exp->ex_uuid != NULL; + } + return 1; +} - /* Choose filehandle version and fsid type based on - * the reference filehandle (if it is in the same export) - * or the export options. - */ - retry: + +static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh) +{ + u8 version; + u8 fsid_type; +retry: version = 1; if (ref_fh && ref_fh->fh_export == exp) { version = ref_fh->fh_handle.fh_version; fsid_type = ref_fh->fh_handle.fh_fsid_type; - if (ref_fh == fhp) - fh_put(ref_fh); ref_fh = NULL; switch (version) { @@ -428,58 +455,66 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, goto retry; } - /* Need to check that this type works for this - * export point. As the fsid -> filesystem mapping - * was guided by user-space, there is no guarantee - * that the filesystem actually supports that fsid - * type. If it doesn't we loop around again without - * ref_fh set. + /* + * As the fsid -> filesystem mapping was guided by + * user-space, there is no guarantee that the filesystem + * actually supports that fsid type. If it doesn't we + * loop around again without ref_fh set. */ - switch(fsid_type) { - case FSID_DEV: - if (!old_valid_dev(ex_dev)) - goto retry; - /* FALL THROUGH */ - case FSID_MAJOR_MINOR: - case FSID_ENCODE_DEV: - if (!(exp->ex_path.dentry->d_inode->i_sb->s_type->fs_flags - & FS_REQUIRES_DEV)) - goto retry; - break; - case FSID_NUM: - if (! (exp->ex_flags & NFSEXP_FSID)) - goto retry; - break; - case FSID_UUID8: - case FSID_UUID16: - if (!root_export) - goto retry; - /* fall through */ - case FSID_UUID4_INUM: - case FSID_UUID16_INUM: - if (exp->ex_uuid == NULL) - goto retry; - break; - } + if (!fsid_type_ok_for_exp(fsid_type, exp)) + goto retry; + } else if (exp->ex_flags & NFSEXP_FSID) { + fsid_type = FSID_NUM; } else if (exp->ex_uuid) { if (fhp->fh_maxsize >= 64) { - if (root_export) + if (is_root_export(exp)) fsid_type = FSID_UUID16; else fsid_type = FSID_UUID16_INUM; } else { - if (root_export) + if (is_root_export(exp)) fsid_type = FSID_UUID8; else fsid_type = FSID_UUID4_INUM; } - } else if (exp->ex_flags & NFSEXP_FSID) - fsid_type = FSID_NUM; - else if (!old_valid_dev(ex_dev)) + } else if (!old_valid_dev(exp_sb(exp)->s_dev)) /* for newer device numbers, we must use a newer fsid format */ fsid_type = FSID_ENCODE_DEV; else fsid_type = FSID_DEV; + fhp->fh_handle.fh_version = version; + if (version) + fhp->fh_handle.fh_fsid_type = fsid_type; +} + +__be32 +fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, + struct svc_fh *ref_fh) +{ + /* ref_fh is a reference file handle. + * if it is non-null and for the same filesystem, then we should compose + * a filehandle which is of the same version, where possible. + * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca + * Then create a 32byte filehandle using nfs_fhbase_old + * + */ + + struct inode * inode = dentry->d_inode; + struct dentry *parent = dentry->d_parent; + __u32 *datap; + dev_t ex_dev = exp_sb(exp)->s_dev; + + dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", + MAJOR(ex_dev), MINOR(ex_dev), + (long) exp->ex_path.dentry->d_inode->i_ino, + parent->d_name.name, dentry->d_name.name, + (inode ? inode->i_ino : 0)); + + /* Choose filehandle version and fsid type based on + * the reference filehandle (if it is in the same export) + * or the export options. + */ + set_version_and_fsid_type(fhp, exp, ref_fh); if (ref_fh == fhp) fh_put(ref_fh); @@ -497,7 +532,7 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, fhp->fh_export = exp; cache_get(&exp->h); - if (version == 0xca) { + if (fhp->fh_handle.fh_version == 0xca) { /* old style filehandle please */ memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE); fhp->fh_handle.fh_size = NFS_FHSIZE; @@ -511,25 +546,24 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, _fh_update_old(dentry, exp, &fhp->fh_handle); } else { int len; - fhp->fh_handle.fh_version = 1; fhp->fh_handle.fh_auth_type = 0; datap = fhp->fh_handle.fh_auth+0; - fhp->fh_handle.fh_fsid_type = fsid_type; - mk_fsid(fsid_type, datap, ex_dev, + mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev, exp->ex_path.dentry->d_inode->i_ino, exp->ex_fsid, exp->ex_uuid); - len = key_len(fsid_type); + len = key_len(fhp->fh_handle.fh_fsid_type); datap += len/4; fhp->fh_handle.fh_size = 4 + len; if (inode) _fh_update(fhp, exp, dentry); - if (fhp->fh_handle.fh_fileid_type == 255) + if (fhp->fh_handle.fh_fileid_type == 255) { + fh_put(fhp); return nfserr_opnotsupp; + } } - nfsd_nr_verified++; return 0; } @@ -586,7 +620,6 @@ fh_put(struct svc_fh *fhp) fhp->fh_pre_saved = 0; fhp->fh_post_saved = 0; #endif - nfsd_nr_put++; } if (exp) { cache_put(&exp->h, &svc_export_cache); @@ -622,8 +655,7 @@ enum fsid_source fsid_source(struct svc_fh *fhp) case FSID_DEV: case FSID_ENCODE_DEV: case FSID_MAJOR_MINOR: - if (fhp->fh_export->ex_path.dentry->d_inode->i_sb->s_type->fs_flags - & FS_REQUIRES_DEV) + if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV) return FSIDSOURCE_DEV; break; case FSID_NUM: