diff --git a/fs/lockd/lockd.h b/fs/lockd/lockd.h index 5c79681b7e95..0be0dac59ea2 100644 --- a/fs/lockd/lockd.h +++ b/fs/lockd/lockd.h @@ -422,6 +422,29 @@ static inline int nlm_compare_locks(const struct file_lock *fl1, &&(fl1->c.flc_type == fl2->c.flc_type || fl2->c.flc_type == F_UNLCK); } +/** + * lockd_set_file_lock_range3 - set the byte range of a file_lock + * @fl: file_lock whose length fields are to be initialized + * @off: starting offset of the lock, in bytes + * @len: length of the byte range, in bytes, or zero + * + * NLMv3 uses a (start, length) representation for lock byte ranges, + * while the kernel's file_lock uses (start, end). Treat a length of + * zero or arithmetic overflow (end wrapping negative when the sum + * exceeds S32_MAX) as "lock to end of file." + */ +static inline void +lockd_set_file_lock_range3(struct file_lock *fl, u32 off, u32 len) +{ + s32 end = off + len - 1; + + fl->fl_start = off; + if (len == 0 || end < 0) + fl->fl_end = OFFSET_MAX; + else + fl->fl_end = end; +} + /** * lockd_set_file_lock_range4 - set the byte range of a file_lock * @fl: file_lock whose length fields are to be initialized diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c index ad37f3611eea..7794e6f88a71 100644 --- a/fs/lockd/svcproc.c +++ b/fs/lockd/svcproc.c @@ -26,6 +26,106 @@ #define NLMDBG_FACILITY NLMDBG_CLIENT +/* + * Size of an NFSv2 file handle, in bytes, which is 32. + * Defined locally to avoid including uapi/linux/nfs2.h. + */ +#define NLM3_FHSIZE 32 + +/* + * Wrapper structures combine xdrgen types with legacy lockd_lock. + * The xdrgen field must be first so the structure can be cast + * to its XDR type for the RPC dispatch layer. + */ +struct nlm_testargs_wrapper { + struct nlm_testargs xdrgen; + struct lockd_lock lock; +}; + +static_assert(offsetof(struct nlm_testargs_wrapper, xdrgen) == 0); + +struct nlm_testres_wrapper { + struct nlm_testres xdrgen; + struct lockd_lock lock; +}; + +static_assert(offsetof(struct nlm_testres_wrapper, xdrgen) == 0); + +static struct nlm_host * +nlm3svc_lookup_host(struct svc_rqst *rqstp, string caller, bool monitored) +{ + struct nlm_host *host; + + if (!nlmsvc_ops) + return NULL; + host = nlmsvc_lookup_host(rqstp, caller.data, caller.len); + if (!host) + return NULL; + if (monitored && nsm_monitor(host) < 0) { + nlmsvc_release_host(host); + return NULL; + } + return host; +} + +static __be32 +nlm3svc_lookup_file(struct svc_rqst *rqstp, struct nlm_host *host, + struct lockd_lock *lock, struct nlm_file **filp, + struct nlm_lock *xdr_lock, unsigned char type) +{ + bool is_test = (rqstp->rq_proc == NLMPROC_TEST || + rqstp->rq_proc == NLMPROC_TEST_MSG); + struct file_lock *fl = &lock->fl; + struct nlm_file *file = NULL; + __be32 error; + int mode; + + if (xdr_lock->fh.len != NLM3_FHSIZE) + return nlm_lck_denied_nolocks; + lock->fh.size = xdr_lock->fh.len; + memcpy(lock->fh.data, xdr_lock->fh.data, xdr_lock->fh.len); + + lock->oh.len = xdr_lock->oh.len; + lock->oh.data = xdr_lock->oh.data; + + lock->svid = xdr_lock->uppid; + lock->lock_start = xdr_lock->l_offset; + lock->lock_len = xdr_lock->l_len; + + locks_init_lock(fl); + fl->c.flc_type = type; + lockd_set_file_lock_range3(fl, lock->lock_start, lock->lock_len); + + mode = lock_to_openmode(fl); + if (is_test) + mode = O_RDWR; + + error = nlm_lookup_file(rqstp, &file, lock, mode); + switch (error) { + case nlm_granted: + break; + case nlm__int__stale_fh: + case nlm__int__failed: + return nlm_lck_denied_nolocks; + default: + return error; + } + *filp = file; + + fl->c.flc_flags = FL_POSIX; + if (is_test) + fl->c.flc_file = nlmsvc_file_file(file); + else + fl->c.flc_file = file->f_file[mode]; + fl->c.flc_pid = current->tgid; + fl->fl_lmops = &nlmsvc_lock_operations; + nlmsvc_locks_init_private(fl, host, (pid_t)lock->svid); + if (!fl->c.flc_owner) + return nlm_lck_denied_nolocks; + + return nlm_granted; +} + #ifdef CONFIG_LOCKD_V4 static inline __be32 cast_status(__be32 status) { @@ -178,10 +278,79 @@ __nlmsvc_proc_test(struct svc_rqst *rqstp, struct lockd_res *resp) return rc; } -static __be32 -nlmsvc_proc_test(struct svc_rqst *rqstp) +/** + * nlmsvc_proc_test - TEST: Check for conflicting lock + * @rqstp: RPC transaction context + * + * Returns: + * %rpc_success: RPC executed successfully. + * %rpc_drop_reply: Do not send an RPC reply. + * + * RPC synopsis: + * nlm_testres NLM_TEST(nlm_testargs) = 1; + * + * Permissible procedure status codes: + * %LCK_GRANTED: The server would be able to grant the + * requested lock. + * %LCK_DENIED: The requested lock conflicted with existing + * lock reservations for the file. + * %LCK_DENIED_NOLOCKS: The server could not allocate the resources + * needed to process the request. + * %LCK_DENIED_GRACE_PERIOD: The server has recently restarted and is + * re-establishing existing locks, and is not + * yet ready to accept normal service requests. + */ +static __be32 nlmsvc_proc_test(struct svc_rqst *rqstp) { - return __nlmsvc_proc_test(rqstp, rqstp->rq_resp); + struct nlm_testargs_wrapper *argp = rqstp->rq_argp; + unsigned char type = argp->xdrgen.exclusive ? F_WRLCK : F_RDLCK; + struct nlm_testres_wrapper *resp = rqstp->rq_resp; + struct nlm_file *file = NULL; + struct nlm_host *host; + + resp->xdrgen.cookie = argp->xdrgen.cookie; + + resp->xdrgen.test_stat.stat = nlm_lck_denied_nolocks; + host = nlm3svc_lookup_host(rqstp, argp->xdrgen.alock.caller_name, false); + if (!host) + goto out; + + resp->xdrgen.test_stat.stat = + nlm3svc_lookup_file(rqstp, host, &argp->lock, &file, + &argp->xdrgen.alock, type); + if (resp->xdrgen.test_stat.stat) + goto out; + + resp->xdrgen.test_stat.stat = + cast_status(nlmsvc_testlock(rqstp, file, host, &argp->lock, + &resp->lock)); + nlmsvc_release_lockowner(&argp->lock); + + if (resp->xdrgen.test_stat.stat == nlm_lck_denied) { + struct lockd_lock *conf = &resp->lock; + struct nlm_holder *holder = &resp->xdrgen.test_stat.u.holder; + + holder->exclusive = (conf->fl.c.flc_type != F_RDLCK); + holder->uppid = conf->svid; + holder->oh.len = conf->oh.len; + holder->oh.data = conf->oh.data; + holder->l_offset = min_t(loff_t, conf->fl.fl_start, + NLM_OFFSET_MAX); + if (conf->fl.fl_end == OFFSET_MAX) + holder->l_len = 0; + else + holder->l_len = min_t(loff_t, + conf->fl.fl_end - + conf->fl.fl_start + 1, + NLM_OFFSET_MAX); + } + +out: + if (file) + nlm_release_file(file); + nlmsvc_release_host(host); + return resp->xdrgen.test_stat.stat == nlm__int__drop_reply ? + rpc_drop_reply : rpc_success; } static __be32 @@ -592,15 +761,15 @@ static const struct svc_procedure nlmsvc_procedures[24] = { .pc_xdrressize = XDR_void, .pc_name = "NULL", }, - [NLMPROC_TEST] = { - .pc_func = nlmsvc_proc_test, - .pc_decode = nlmsvc_decode_testargs, - .pc_encode = nlmsvc_encode_testres, - .pc_argsize = sizeof(struct lockd_args), - .pc_argzero = sizeof(struct lockd_args), - .pc_ressize = sizeof(struct lockd_res), - .pc_xdrressize = Ck+St+2+No+Rg, - .pc_name = "TEST", + [NLM_TEST] = { + .pc_func = nlmsvc_proc_test, + .pc_decode = nlm_svc_decode_nlm_testargs, + .pc_encode = nlm_svc_encode_nlm_testres, + .pc_argsize = sizeof(struct nlm_testargs_wrapper), + .pc_argzero = 0, + .pc_ressize = sizeof(struct nlm_testres_wrapper), + .pc_xdrressize = NLM3_nlm_testres_sz, + .pc_name = "TEST", }, [NLMPROC_LOCK] = { .pc_func = nlmsvc_proc_lock, @@ -828,6 +997,8 @@ static const struct svc_procedure nlmsvc_procedures[24] = { * Storage requirements for XDR arguments and results */ union nlmsvc_xdrstore { + struct nlm_testargs_wrapper testargs; + struct nlm_testres_wrapper testres; struct lockd_args args; struct lockd_res res; struct lockd_reboot reboot;