From 731f3f482ad3b2c58a1af2d0a9a634a82803706a Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 21 Jan 2011 03:05:28 +0000 Subject: NFS: nfsacl_{encode,decode} should return signed integer Clean up. The nfsacl_encode() and nfsacl_decode() functions return negative errno values, and each call site verifies that the returned value is not negative. Change the synopsis of both of these functions to reflect this usage. Document the synopsis and return values. Reported-by: Trond Myklebust Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- include/linux/nfsacl.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/nfsacl.h b/include/linux/nfsacl.h index f321b578edeb..fabcb1e5c460 100644 --- a/include/linux/nfsacl.h +++ b/include/linux/nfsacl.h @@ -51,10 +51,10 @@ nfsacl_size(struct posix_acl *acl_access, struct posix_acl *acl_default) return w; } -extern unsigned int +extern int nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode, struct posix_acl *acl, int encode_entries, int typeflag); -extern unsigned int +extern int nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt, struct posix_acl **pacl); -- cgit v1.2.3 From f61f6da0d53842e849bab7f69e1431bd3de1136d Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 21 Jan 2011 03:05:38 +0000 Subject: NFS: Prevent memory allocation failure in nfsacl_encode() nfsacl_encode() allocates memory in certain cases. This of course is not guaranteed to work. Since commit 9f06c719 "SUNRPC: New xdr_streams XDR encoder API", the kernel's XDR encoders can't return a result indicating possibly a failure, so a memory allocation failure in nfsacl_encode() has become fatal (ie, the XDR code Oopses) in some cases. However, the allocated memory is a tiny fixed amount, on the order of 40-50 bytes. We can easily use a stack-allocated buffer for this, with only a wee bit of nose-holding. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs3acl.c | 4 ++-- fs/nfs_common/nfsacl.c | 22 +++++++++++++++------- fs/posix_acl.c | 17 +++++++++++++---- include/linux/posix_acl.h | 1 + 4 files changed, 31 insertions(+), 13 deletions(-) (limited to 'include/linux') diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c index 9f88c5f4c7e2..274342771655 100644 --- a/fs/nfs/nfs3acl.c +++ b/fs/nfs/nfs3acl.c @@ -311,8 +311,8 @@ static int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl, if (!nfs_server_capable(inode, NFS_CAP_ACLS)) goto out; - /* We are doing this here, because XDR marshalling can only - return -ENOMEM. */ + /* We are doing this here because XDR marshalling does not + * return any results, it BUGs. */ status = -ENOSPC; if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES) goto out; diff --git a/fs/nfs_common/nfsacl.c b/fs/nfs_common/nfsacl.c index a3e78bd18679..84c27d69d421 100644 --- a/fs/nfs_common/nfsacl.c +++ b/fs/nfs_common/nfsacl.c @@ -42,6 +42,11 @@ struct nfsacl_encode_desc { gid_t gid; }; +struct nfsacl_simple_acl { + struct posix_acl acl; + struct posix_acl_entry ace[4]; +}; + static int xdr_nfsace_encode(struct xdr_array2_desc *desc, void *elem) { @@ -99,17 +104,22 @@ int nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode, .uid = inode->i_uid, .gid = inode->i_gid, }; + struct nfsacl_simple_acl aclbuf; int err; - struct posix_acl *acl2 = NULL; if (entries > NFS_ACL_MAX_ENTRIES || xdr_encode_word(buf, base, entries)) return -EINVAL; if (encode_entries && acl && acl->a_count == 3) { - /* Fake up an ACL_MASK entry. */ - acl2 = posix_acl_alloc(4, GFP_KERNEL); - if (!acl2) - return -ENOMEM; + struct posix_acl *acl2 = &aclbuf.acl; + + /* Avoid the use of posix_acl_alloc(). nfsacl_encode() is + * invoked in contexts where a memory allocation failure is + * fatal. Fortunately this fake ACL is small enough to + * construct on the stack. */ + memset(acl2, 0, sizeof(acl2)); + posix_acl_init(acl2, 4); + /* Insert entries in canonical order: other orders seem to confuse Solaris VxFS. */ acl2->a_entries[0] = acl->a_entries[0]; /* ACL_USER_OBJ */ @@ -120,8 +130,6 @@ int nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode, nfsacl_desc.acl = acl2; } err = xdr_encode_array2(buf, base + 4, &nfsacl_desc.desc); - if (acl2) - posix_acl_release(acl2); if (!err) err = 8 + nfsacl_desc.desc.elem_size * nfsacl_desc.desc.array_len; diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 39df95a0ec25..b1cf6bf4b41d 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -22,6 +22,7 @@ #include +EXPORT_SYMBOL(posix_acl_init); EXPORT_SYMBOL(posix_acl_alloc); EXPORT_SYMBOL(posix_acl_clone); EXPORT_SYMBOL(posix_acl_valid); @@ -31,6 +32,16 @@ EXPORT_SYMBOL(posix_acl_create_masq); EXPORT_SYMBOL(posix_acl_chmod_masq); EXPORT_SYMBOL(posix_acl_permission); +/* + * Init a fresh posix_acl + */ +void +posix_acl_init(struct posix_acl *acl, int count) +{ + atomic_set(&acl->a_refcount, 1); + acl->a_count = count; +} + /* * Allocate a new ACL with the specified number of entries. */ @@ -40,10 +51,8 @@ posix_acl_alloc(int count, gfp_t flags) const size_t size = sizeof(struct posix_acl) + count * sizeof(struct posix_acl_entry); struct posix_acl *acl = kmalloc(size, flags); - if (acl) { - atomic_set(&acl->a_refcount, 1); - acl->a_count = count; - } + if (acl) + posix_acl_init(acl, count); return acl; } diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h index d68283a898bb..54211c1cd926 100644 --- a/include/linux/posix_acl.h +++ b/include/linux/posix_acl.h @@ -71,6 +71,7 @@ posix_acl_release(struct posix_acl *acl) /* posix_acl.c */ +extern void posix_acl_init(struct posix_acl *, int); extern struct posix_acl *posix_acl_alloc(int, gfp_t); extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t); extern int posix_acl_valid(const struct posix_acl *); -- cgit v1.2.3 From 778be232a207e79088ba70d832ac25dfea6fbf1a Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Tue, 25 Jan 2011 15:38:01 +0000 Subject: NFS do not find client in NFSv4 pg_authenticate The information required to find the nfs_client cooresponding to the incoming back channel request is contained in the NFS layer. Perform minimal checking in the RPC layer pg_authenticate method, and push more detailed checking into the NFS layer where the nfs_client can be found. Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust --- fs/nfs/callback.c | 109 +++++++++++----------------------------- fs/nfs/callback.h | 4 +- fs/nfs/callback_proc.c | 10 +--- fs/nfs/callback_xdr.c | 5 +- fs/nfs/client.c | 15 ++---- fs/nfs/internal.h | 3 +- fs/nfs/nfs4state.c | 6 --- include/linux/sunrpc/bc_xprt.h | 13 ----- include/linux/sunrpc/svc_xprt.h | 1 - net/sunrpc/svcsock.c | 4 +- 10 files changed, 42 insertions(+), 128 deletions(-) (limited to 'include/linux') diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c index 199016528fcb..e3d294269058 100644 --- a/fs/nfs/callback.c +++ b/fs/nfs/callback.c @@ -134,33 +134,6 @@ out_err: } #if defined(CONFIG_NFS_V4_1) -/* - * * CB_SEQUENCE operations will fail until the callback sessionid is set. - * */ -int nfs4_set_callback_sessionid(struct nfs_client *clp) -{ - struct svc_serv *serv = clp->cl_rpcclient->cl_xprt->bc_serv; - struct nfs4_sessionid *bc_sid; - - if (!serv->sv_bc_xprt) - return -EINVAL; - - /* on success freed in xprt_free */ - bc_sid = kmalloc(sizeof(struct nfs4_sessionid), GFP_KERNEL); - if (!bc_sid) - return -ENOMEM; - memcpy(bc_sid->data, &clp->cl_session->sess_id.data, - NFS4_MAX_SESSIONID_LEN); - spin_lock_bh(&serv->sv_cb_lock); - serv->sv_bc_xprt->xpt_bc_sid = bc_sid; - spin_unlock_bh(&serv->sv_cb_lock); - dprintk("%s set xpt_bc_sid=%u:%u:%u:%u for sv_bc_xprt %p\n", __func__, - ((u32 *)bc_sid->data)[0], ((u32 *)bc_sid->data)[1], - ((u32 *)bc_sid->data)[2], ((u32 *)bc_sid->data)[3], - serv->sv_bc_xprt); - return 0; -} - /* * The callback service for NFSv4.1 callbacks */ @@ -266,10 +239,6 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt, struct nfs_callback_data *cb_info) { } -int nfs4_set_callback_sessionid(struct nfs_client *clp) -{ - return 0; -} #endif /* CONFIG_NFS_V4_1 */ /* @@ -359,78 +328,58 @@ void nfs_callback_down(int minorversion) mutex_unlock(&nfs_callback_mutex); } -static int check_gss_callback_principal(struct nfs_client *clp, - struct svc_rqst *rqstp) +/* Boolean check of RPC_AUTH_GSS principal */ +int +check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp) { struct rpc_clnt *r = clp->cl_rpcclient; char *p = svc_gss_principal(rqstp); + if (rqstp->rq_authop->flavour != RPC_AUTH_GSS) + return 1; + /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */ if (clp->cl_minorversion != 0) - return SVC_DROP; + return 0; /* * It might just be a normal user principal, in which case * userspace won't bother to tell us the name at all. */ if (p == NULL) - return SVC_DENIED; + return 0; /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */ if (memcmp(p, "nfs@", 4) != 0) - return SVC_DENIED; + return 0; p += 4; if (strcmp(p, r->cl_server) != 0) - return SVC_DENIED; - return SVC_OK; + return 0; + return 1; } -/* pg_authenticate method helper */ -static struct nfs_client *nfs_cb_find_client(struct svc_rqst *rqstp) -{ - struct nfs4_sessionid *sessionid = bc_xprt_sid(rqstp); - int is_cb_compound = rqstp->rq_proc == CB_COMPOUND ? 1 : 0; - - dprintk("--> %s rq_proc %d\n", __func__, rqstp->rq_proc); - if (svc_is_backchannel(rqstp)) - /* Sessionid (usually) set after CB_NULL ping */ - return nfs4_find_client_sessionid(svc_addr(rqstp), sessionid, - is_cb_compound); - else - /* No callback identifier in pg_authenticate */ - return nfs4_find_client_no_ident(svc_addr(rqstp)); -} - -/* pg_authenticate method for nfsv4 callback threads. */ +/* + * pg_authenticate method for nfsv4 callback threads. + * + * The authflavor has been negotiated, so an incorrect flavor is a server + * bug. Drop packets with incorrect authflavor. + * + * All other checking done after NFS decoding where the nfs_client can be + * found in nfs4_callback_compound + */ static int nfs_callback_authenticate(struct svc_rqst *rqstp) { - struct nfs_client *clp; - RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); - int ret = SVC_OK; - - /* Don't talk to strangers */ - clp = nfs_cb_find_client(rqstp); - if (clp == NULL) - return SVC_DROP; - - dprintk("%s: %s NFSv4 callback!\n", __func__, - svc_print_addr(rqstp, buf, sizeof(buf))); - switch (rqstp->rq_authop->flavour) { - case RPC_AUTH_NULL: - if (rqstp->rq_proc != CB_NULL) - ret = SVC_DENIED; - break; - case RPC_AUTH_UNIX: - break; - case RPC_AUTH_GSS: - ret = check_gss_callback_principal(clp, rqstp); - break; - default: - ret = SVC_DENIED; + case RPC_AUTH_NULL: + if (rqstp->rq_proc != CB_NULL) + return SVC_DROP; + break; + case RPC_AUTH_GSS: + /* No RPC_AUTH_GSS support yet in NFSv4.1 */ + if (svc_is_backchannel(rqstp)) + return SVC_DROP; } - nfs_put_client(clp); - return ret; + return SVC_OK; } /* diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h index d3b44f9bd747..46d93ce7311b 100644 --- a/fs/nfs/callback.h +++ b/fs/nfs/callback.h @@ -7,6 +7,7 @@ */ #ifndef __LINUX_FS_NFS_CALLBACK_H #define __LINUX_FS_NFS_CALLBACK_H +#include #define NFS4_CALLBACK 0x40000000 #define NFS4_CALLBACK_XDRSIZE 2048 @@ -37,7 +38,6 @@ enum nfs4_callback_opnum { struct cb_process_state { __be32 drc_status; struct nfs_client *clp; - struct nfs4_sessionid *svc_sid; /* v4.1 callback service sessionid */ }; struct cb_compound_hdr_arg { @@ -168,7 +168,7 @@ extern unsigned nfs4_callback_layoutrecall( extern void nfs4_check_drain_bc_complete(struct nfs4_session *ses); extern void nfs4_cb_take_slot(struct nfs_client *clp); #endif /* CONFIG_NFS_V4_1 */ - +extern int check_gss_callback_principal(struct nfs_client *, struct svc_rqst *); extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res, struct cb_process_state *cps); diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c index 4bb91cb2620d..829f406e91dd 100644 --- a/fs/nfs/callback_proc.c +++ b/fs/nfs/callback_proc.c @@ -373,17 +373,11 @@ __be32 nfs4_callback_sequence(struct cb_sequenceargs *args, { struct nfs_client *clp; int i; - __be32 status; + __be32 status = htonl(NFS4ERR_BADSESSION); cps->clp = NULL; - status = htonl(NFS4ERR_BADSESSION); - /* Incoming session must match the callback session */ - if (memcmp(&args->csa_sessionid, cps->svc_sid, NFS4_MAX_SESSIONID_LEN)) - goto out; - - clp = nfs4_find_client_sessionid(args->csa_addr, - &args->csa_sessionid, 1); + clp = nfs4_find_client_sessionid(args->csa_addr, &args->csa_sessionid); if (clp == NULL) goto out; diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c index 23112c263f81..14e0f9371d14 100644 --- a/fs/nfs/callback_xdr.c +++ b/fs/nfs/callback_xdr.c @@ -794,10 +794,9 @@ static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *r if (hdr_arg.minorversion == 0) { cps.clp = nfs4_find_client_ident(hdr_arg.cb_ident); - if (!cps.clp) + if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp)) return rpc_drop_reply; - } else - cps.svc_sid = bc_xprt_sid(rqstp); + } hdr_res.taglen = hdr_arg.taglen; hdr_res.tag = hdr_arg.tag; diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 192f2f860265..bd3ca32879e7 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -1206,16 +1206,11 @@ nfs4_find_client_ident(int cb_ident) * For CB_COMPOUND calls, find a client by IP address, protocol version, * minorversion, and sessionID * - * CREATE_SESSION triggers a CB_NULL ping from servers. The callback service - * sessionid can only be set after the CREATE_SESSION return, so a CB_NULL - * can arrive before the callback sessionid is set. For CB_NULL calls, - * find a client by IP address protocol version, and minorversion. - * * Returns NULL if no such client */ struct nfs_client * nfs4_find_client_sessionid(const struct sockaddr *addr, - struct nfs4_sessionid *sid, int is_cb_compound) + struct nfs4_sessionid *sid) { struct nfs_client *clp; @@ -1227,9 +1222,9 @@ nfs4_find_client_sessionid(const struct sockaddr *addr, if (!nfs4_has_session(clp)) continue; - /* Match sessionid unless cb_null call*/ - if (is_cb_compound && (memcmp(clp->cl_session->sess_id.data, - sid->data, NFS4_MAX_SESSIONID_LEN) != 0)) + /* Match sessionid*/ + if (memcmp(clp->cl_session->sess_id.data, + sid->data, NFS4_MAX_SESSIONID_LEN) != 0) continue; atomic_inc(&clp->cl_count); @@ -1244,7 +1239,7 @@ nfs4_find_client_sessionid(const struct sockaddr *addr, struct nfs_client * nfs4_find_client_sessionid(const struct sockaddr *addr, - struct nfs4_sessionid *sid, int is_cb_compound) + struct nfs4_sessionid *sid) { return NULL; } diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 4644f04b4b46..cf9fdbdabc67 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -133,8 +133,7 @@ extern void nfs_put_client(struct nfs_client *); extern struct nfs_client *nfs4_find_client_no_ident(const struct sockaddr *); extern struct nfs_client *nfs4_find_client_ident(int); extern struct nfs_client * -nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *, - int); +nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *); extern struct nfs_server *nfs_create_server( const struct nfs_parsed_mount_data *, struct nfs_fh *); diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 2336d532cf66..e6742b57a04c 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -232,12 +232,6 @@ int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred) status = nfs4_proc_create_session(clp); if (status != 0) goto out; - status = nfs4_set_callback_sessionid(clp); - if (status != 0) { - printk(KERN_WARNING "Sessionid not set. No callback service\n"); - nfs_callback_down(1); - status = 0; - } nfs41_setup_state_renewal(clp); nfs_mark_client_ready(clp, NFS_CS_READY); out: diff --git a/include/linux/sunrpc/bc_xprt.h b/include/linux/sunrpc/bc_xprt.h index c50b458b8a3f..082884295f80 100644 --- a/include/linux/sunrpc/bc_xprt.h +++ b/include/linux/sunrpc/bc_xprt.h @@ -47,14 +47,6 @@ static inline int svc_is_backchannel(const struct svc_rqst *rqstp) return 1; return 0; } -static inline struct nfs4_sessionid *bc_xprt_sid(struct svc_rqst *rqstp) -{ - if (svc_is_backchannel(rqstp)) - return (struct nfs4_sessionid *) - rqstp->rq_server->sv_bc_xprt->xpt_bc_sid; - return NULL; -} - #else /* CONFIG_NFS_V4_1 */ static inline int xprt_setup_backchannel(struct rpc_xprt *xprt, unsigned int min_reqs) @@ -67,11 +59,6 @@ static inline int svc_is_backchannel(const struct svc_rqst *rqstp) return 0; } -static inline struct nfs4_sessionid *bc_xprt_sid(struct svc_rqst *rqstp) -{ - return NULL; -} - static inline void xprt_free_bc_request(struct rpc_rqst *req) { } diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h index 059877b4d85b..7ad9751a0d87 100644 --- a/include/linux/sunrpc/svc_xprt.h +++ b/include/linux/sunrpc/svc_xprt.h @@ -77,7 +77,6 @@ struct svc_xprt { size_t xpt_remotelen; /* length of address */ struct rpc_wait_queue xpt_bc_pending; /* backchannel wait queue */ struct list_head xpt_users; /* callbacks on free */ - void *xpt_bc_sid; /* back channel session ID */ struct net *xpt_net; struct rpc_xprt *xpt_bc_xprt; /* NFSv4.1 backchannel */ diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 7bd3bbba4710..d802e941d365 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1609,9 +1609,7 @@ static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv, */ static void svc_bc_sock_free(struct svc_xprt *xprt) { - if (xprt) { - kfree(xprt->xpt_bc_sid); + if (xprt) kfree(container_of(xprt, struct svc_sock, sk_xprt)); - } } #endif /* CONFIG_NFS_V4_1 */ -- cgit v1.2.3