/* * Copyright (C) 2007 * * Author: Eric Biederman * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2 of the * License. */ #include #include #include #include #include #include #include #include "util.h" static void *get_ipc(struct ctl_table *table) { char *which = table->data; struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns; return which; } #ifdef CONFIG_PROC_SYSCTL static int proc_ipc_dointvec(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table ipc_table; memcpy(&ipc_table, table, sizeof(ipc_table)); ipc_table.data = get_ipc(table); return proc_dointvec(&ipc_table, write, buffer, lenp, ppos); } static int proc_ipc_dointvec_minmax(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table ipc_table; memcpy(&ipc_table, table, sizeof(ipc_table)); ipc_table.data = get_ipc(table); return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); } static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ipc_namespace *ns = current->nsproxy->ipc_ns; int err = proc_ipc_dointvec_minmax(table, write, buffer, lenp, ppos); if (err < 0) return err; if (ns->shm_rmid_forced) shm_destroy_orphaned(ns); return err; } static int proc_ipc_doulongvec_minmax(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table ipc_table; memcpy(&ipc_table, table, sizeof(ipc_table)); ipc_table.data = get_ipc(table); return proc_doulongvec_minmax(&ipc_table, write, buffer, lenp, ppos); } static int proc_ipc_auto_msgmni(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table ipc_table; int dummy = 0; memcpy(&ipc_table, table, sizeof(ipc_table)); ipc_table.data = &dummy; if (write) pr_info_once("writing to auto_msgmni has no effect"); return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); } #else #define proc_ipc_doulongvec_minmax NULL #define proc_ipc_dointvec NULL #define proc_ipc_dointvec_minmax NULL #define proc_ipc_dointvec_minmax_orphans NULL #define proc_ipc_auto_msgmni NULL #endif static int zero; static int one = 1; static int int_max = INT_MAX; static struct ctl_table ipc_kern_table[] = { { .procname = "shmmax", .data = &init_ipc_ns.shm_ctlmax, .maxlen = sizeof(init_ipc_ns.shm_ctlmax), .mode = 0644, .proc_handler = proc_ipc_doulongvec_minmax, }, { .procname = "shmall", .data = &init_ipc_ns.shm_ctlall, .maxlen = sizeof(init_ipc_ns.shm_ctlall), .mode = 0644, .proc_handler = proc_ipc_doulongvec_minmax, }, { .procname = "shmmni", .data = &init_ipc_ns.shm_ctlmni, .maxlen = sizeof(init_ipc_ns.shm_ctlmni), .mode = 0644, .proc_handler = proc_ipc_dointvec, }, { .procname = "shm_rmid_forced", .data = &init_ipc_ns.shm_rmid_forced, .maxlen = sizeof(init_ipc_ns.shm_rmid_forced), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax_orphans, .extra1 = &zero, .extra2 = &one, }, { .procname = "msgmax", .data = &init_ipc_ns.msg_ctlmax, .maxlen = sizeof(init_ipc_ns.msg_ctlmax), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { .procname = "msgmni", .data = &init_ipc_ns.msg_ctlmni, .maxlen = sizeof(init_ipc_ns.msg_ctlmni), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { .procname = "auto_msgmni", .data = NULL, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_ipc_auto_msgmni, .extra1 = &zero, .extra2 = &one, }, { .procname = "msgmnb", .data = &init_ipc_ns.msg_ctlmnb, .maxlen = sizeof(init_ipc_ns.msg_ctlmnb), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { .procname = "sem", .data = &init_ipc_ns.sem_ctls, .maxlen = 4*sizeof(int), .mode = 0644, .proc_handler = proc_ipc_dointvec, }, #ifdef CONFIG_CHECKPOINT_RESTORE { .procname = "sem_next_id", .data = &init_ipc_ns.ids[IPC_SEM_IDS].next_id, .maxlen = sizeof(init_ipc_ns.ids[IPC_SEM_IDS].next_id), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { .procname = "msg_next_id", .data = &init_ipc_ns.ids[IPC_MSG_IDS].next_id, .maxlen = sizeof(init_ipc_ns.ids[IPC_MSG_IDS].next_id), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { .procname = "shm_next_id", .data = &init_ipc_ns.ids[IPC_SHM_IDS].next_id, .maxlen = sizeof(init_ipc_ns.ids[IPC_SHM_IDS].next_id), .mode = 0644, .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, #endif {} }; static struct ctl_table ipc_root_table[] = { { .procname = "kernel", .mode = 0555, .child = ipc_kern_table, }, {} }; static int __init ipc_sysctl_init(void) { register_sysctl_table(ipc_root_table); return 0; } device_initcall(ipc_sysctl_init); -next.git/tree/net/x25?h=nds-private-remove&id=433e19cf33d34bb6751c874a9c00980552fe508c'>net/x25 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')