/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. */ #include #include #include #include #include #include #include #include #include /* If kernel subsystem is allowing eBPF programs to call this function, * inside its own verifier_ops->get_func_proto() callback it should return * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments * * Different map implementations will rely on rcu in map methods * lookup/update/delete, therefore eBPF programs must run under rcu lock * if program is allowed to access maps, so check rcu_read_lock_held in * all three functions. */ BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key) { WARN_ON_ONCE(!rcu_read_lock_held()); return (unsigned long) map->ops->map_lookup_elem(map, key); } const struct bpf_func_proto bpf_map_lookup_elem_proto = { .func = bpf_map_lookup_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }; BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key, void *, value, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); return map->ops->map_update_elem(map, key, value, flags); } const struct bpf_func_proto bpf_map_update_elem_proto = { .func = bpf_map_update_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, .arg3_type = ARG_PTR_TO_MAP_VALUE, .arg4_type = ARG_ANYTHING, }; BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key) { WARN_ON_ONCE(!rcu_read_lock_held()); return map->ops->map_delete_elem(map, key); } const struct bpf_func_proto bpf_map_delete_elem_proto = { .func = bpf_map_delete_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }; const struct bpf_func_proto bpf_get_prandom_u32_proto = { .func = bpf_user_rnd_u32, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_smp_processor_id) { return smp_processor_id(); } const struct bpf_func_proto bpf_get_smp_processor_id_proto = { .func = bpf_get_smp_processor_id, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_numa_node_id) { return numa_node_id(); } const struct bpf_func_proto bpf_get_numa_node_id_proto = { .func = bpf_get_numa_node_id, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_ktime_get_ns) { /* NMI safe access to clock monotonic */ return ktime_get_mono_fast_ns(); } const struct bpf_func_proto bpf_ktime_get_ns_proto = { .func = bpf_ktime_get_ns, .gpl_only = true, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_current_pid_tgid) { struct task_struct *task = current; if (unlikely(!task)) return -EINVAL; return (u64) task->tgid << 32 | task->pid; } const struct bpf_func_proto bpf_get_current_pid_tgid_proto = { .func = bpf_get_current_pid_tgid, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_current_uid_gid) { struct task_struct *task = current; kuid_t uid; kgid_t gid; if (unlikely(!task)) return -EINVAL; current_uid_gid(&uid, &gid); return (u64) from_kgid(&init_user_ns, gid) << 32 | from_kuid(&init_user_ns, uid); } const struct bpf_func_proto bpf_get_current_uid_gid_proto = { .func = bpf_get_current_uid_gid, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size) { struct task_struct *task = current; if (unlikely(!task)) goto err_clear; strncpy(buf, task->comm, size); /* Verifier guarantees that size > 0. For task->comm exceeding * size, guarantee that buf is %NUL-terminated. Unconditionally * done here to save the size test. */ buf[size - 1] = 0; return 0; err_clear: memset(buf, 0, size); return -EINVAL; } const struct bpf_func_proto bpf_get_current_comm_proto = { .func = bpf_get_current_comm, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE, }; Kroah-Hartman <gregkh@linuxfoundation.org>2017-01-31 10:59:48 +0100 commit433e19cf33d34bb6751c874a9c00980552fe508c (patch) treece6547ef2987fbb289fa28f03536328a42781651 /net/x25/x25_subr.c parent191e885a2e130e639bb0c8ee350d7047294f2ce6 (diff)
Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") added the proper mb(), but removed the test "prev_write_sz < pending_sz" when making the signal decision. As a result, the guest can signal the host unnecessarily, and then the host can throttle the guest because the host thinks the guest is buggy or malicious; finally the user running stress test can perceive intermittent freeze of the guest. This patch brings back the test, and properly handles the in-place consumption APIs used by NetVSC (see get_next_pkt_raw(), put_pkt_raw() and commit_rd_index()). Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") Signed-off-by: Dexuan Cui <decui@microsoft.com> Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/x25/x25_subr.c')