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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
| commit | 3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch) | |
| tree | b767d7f6e26bc64334d3f14f8422d187239dc45d /ipc/ipc_sysctl.c | |
| download | linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip | |
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe:
- Fix a task_work add use-after-free with SQPOLL.
The sqpoll thread could pop and complete the last request while
io_req_normal_work_add() was still looking at them after the mpscq
push.
Use the same approach as DEFER_TASKRUN to protect from that, holding
an RCU read lock across the add, and have exit wait for an RCU grace
period for SQPOLL rings as well.
- CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
rings
- Mark the source filter table as COW when cloning bpf filters, so
registering another filter on the source doesn't modify the shared
table in place
- Initialize the task context before running the BPF loop
- Requeue zcrx multishot receives stopped by a local resource
- End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)
* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring: fix task_work add use-after-free with SQPOLL
io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
io_uring/zcrx: requeue multishot receives stopped by a local resource
io_uring: initialize task context before running the BPF loop
io_uring: zero big_cqe for aux CQEs on CQE32 rings
io_uring: fix free entry check for 32b CQEs on CQE32 rings
io_uring: only post the dummy skip CQE on CQE_MIXED rings
io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'ipc/ipc_sysctl.c')
| -rw-r--r-- | ipc/ipc_sysctl.c | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c new file mode 100644 index 000000000..d038d9442 --- /dev/null +++ b/ipc/ipc_sysctl.c @@ -0,0 +1,334 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2007 + * + * Author: Eric Biederman <ebiederm@xmision.com> + */ + +#include <linux/module.h> +#include <linux/ipc.h> +#include <linux/nsproxy.h> +#include <linux/sysctl.h> +#include <linux/uaccess.h> +#include <linux/capability.h> +#include <linux/ipc_namespace.h> +#include <linux/msg.h> +#include <linux/slab.h> +#include <linux/cred.h> +#include "util.h" + +static int proc_ipc_dointvec_minmax_orphans(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ipc_namespace *ns = + container_of(table->data, struct ipc_namespace, shm_rmid_forced); + int err; + + err = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + + if (err < 0) + return err; + if (write && ns->shm_rmid_forced) + shm_destroy_orphaned(ns); + return err; +} + +static int proc_ipc_auto_msgmni(const struct ctl_table *table, int write, + void *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); +} + +static int proc_ipc_sem_dointvec(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct ipc_namespace *ns = + container_of(table->data, struct ipc_namespace, sem_ctls); + int ret, semmni; + + semmni = ns->sem_ctls[3]; + ret = proc_dointvec(table, write, buffer, lenp, ppos); + + if (!ret) + ret = sem_check_semmni(ns); + + /* + * Reset the semmni value if an error happens. + */ + if (ret) + ns->sem_ctls[3] = semmni; + return ret; +} + +int ipc_mni = IPCMNI; +int ipc_mni_shift = IPCMNI_SHIFT; +int ipc_min_cycle = RADIX_TREE_MAP_SIZE; + +static const struct ctl_table ipc_sysctls[] = { + { + .procname = "shmmax", + .data = &init_ipc_ns.shm_ctlmax, + .maxlen = sizeof(init_ipc_ns.shm_ctlmax), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + }, + { + .procname = "shmall", + .data = &init_ipc_ns.shm_ctlall, + .maxlen = sizeof(init_ipc_ns.shm_ctlall), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + }, + { + .procname = "shmmni", + .data = &init_ipc_ns.shm_ctlmni, + .maxlen = sizeof(init_ipc_ns.shm_ctlmni), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = &ipc_mni, + }, + { + .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 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { + .procname = "msgmax", + .data = &init_ipc_ns.msg_ctlmax, + .maxlen = sizeof(init_ipc_ns.msg_ctlmax), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_INT_MAX, + }, + { + .procname = "msgmni", + .data = &init_ipc_ns.msg_ctlmni, + .maxlen = sizeof(init_ipc_ns.msg_ctlmni), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = &ipc_mni, + }, + { + .procname = "auto_msgmni", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_ipc_auto_msgmni, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { + .procname = "msgmnb", + .data = &init_ipc_ns.msg_ctlmnb, + .maxlen = sizeof(init_ipc_ns.msg_ctlmnb), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_INT_MAX, + }, + { + .procname = "sem", + .data = &init_ipc_ns.sem_ctls, + .maxlen = 4*sizeof(int), + .mode = 0644, + .proc_handler = proc_ipc_sem_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 = 0444, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_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 = 0444, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_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 = 0444, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_INT_MAX, + }, +#endif +}; + +static struct ctl_table_set *set_lookup(struct ctl_table_root *root) +{ + return ¤t->nsproxy->ipc_ns->ipc_set; +} + +static int set_is_seen(struct ctl_table_set *set) +{ + return ¤t->nsproxy->ipc_ns->ipc_set == set; +} + +static void ipc_set_ownership(struct ctl_table_header *head, + kuid_t *uid, kgid_t *gid) +{ + struct ipc_namespace *ns = + container_of(head->set, struct ipc_namespace, ipc_set); + + kuid_t ns_root_uid = make_kuid(ns->user_ns, 0); + kgid_t ns_root_gid = make_kgid(ns->user_ns, 0); + + *uid = uid_valid(ns_root_uid) ? ns_root_uid : GLOBAL_ROOT_UID; + *gid = gid_valid(ns_root_gid) ? ns_root_gid : GLOBAL_ROOT_GID; +} + +static int ipc_permissions(struct ctl_table_header *head, const struct ctl_table *table) +{ + int mode = table->mode; + +#ifdef CONFIG_CHECKPOINT_RESTORE + struct ipc_namespace *ns = + container_of(head->set, struct ipc_namespace, ipc_set); + + if (((table->data == &ns->ids[IPC_SEM_IDS].next_id) || + (table->data == &ns->ids[IPC_MSG_IDS].next_id) || + (table->data == &ns->ids[IPC_SHM_IDS].next_id)) && + checkpoint_restore_ns_capable_noaudit(ns->user_ns)) + mode = 0666; + else +#endif + { + kuid_t ns_root_uid; + kgid_t ns_root_gid; + + ipc_set_ownership(head, &ns_root_uid, &ns_root_gid); + + if (uid_eq(current_euid(), ns_root_uid)) + mode >>= 6; + + else if (in_egroup_p(ns_root_gid)) + mode >>= 3; + } + + mode &= 7; + + return (mode << 6) | (mode << 3) | mode; +} + +static struct ctl_table_root set_root = { + .lookup = set_lookup, + .permissions = ipc_permissions, + .set_ownership = ipc_set_ownership, +}; + +bool setup_ipc_sysctls(struct ipc_namespace *ns) +{ + struct ctl_table *tbl; + + setup_sysctl_set(&ns->ipc_set, &set_root, set_is_seen); + + tbl = kmemdup(ipc_sysctls, sizeof(ipc_sysctls), GFP_KERNEL); + if (tbl) { + int i; + + for (i = 0; i < ARRAY_SIZE(ipc_sysctls); i++) { + if (tbl[i].data == &init_ipc_ns.shm_ctlmax) + tbl[i].data = &ns->shm_ctlmax; + + else if (tbl[i].data == &init_ipc_ns.shm_ctlall) + tbl[i].data = &ns->shm_ctlall; + + else if (tbl[i].data == &init_ipc_ns.shm_ctlmni) + tbl[i].data = &ns->shm_ctlmni; + + else if (tbl[i].data == &init_ipc_ns.shm_rmid_forced) + tbl[i].data = &ns->shm_rmid_forced; + + else if (tbl[i].data == &init_ipc_ns.msg_ctlmax) + tbl[i].data = &ns->msg_ctlmax; + + else if (tbl[i].data == &init_ipc_ns.msg_ctlmni) + tbl[i].data = &ns->msg_ctlmni; + + else if (tbl[i].data == &init_ipc_ns.msg_ctlmnb) + tbl[i].data = &ns->msg_ctlmnb; + + else if (tbl[i].data == &init_ipc_ns.sem_ctls) + tbl[i].data = &ns->sem_ctls; +#ifdef CONFIG_CHECKPOINT_RESTORE + else if (tbl[i].data == &init_ipc_ns.ids[IPC_SEM_IDS].next_id) + tbl[i].data = &ns->ids[IPC_SEM_IDS].next_id; + + else if (tbl[i].data == &init_ipc_ns.ids[IPC_MSG_IDS].next_id) + tbl[i].data = &ns->ids[IPC_MSG_IDS].next_id; + + else if (tbl[i].data == &init_ipc_ns.ids[IPC_SHM_IDS].next_id) + tbl[i].data = &ns->ids[IPC_SHM_IDS].next_id; +#endif + else + tbl[i].data = NULL; + } + + ns->ipc_sysctls = __register_sysctl_table(&ns->ipc_set, "kernel", tbl, + ARRAY_SIZE(ipc_sysctls)); + } + if (!ns->ipc_sysctls) { + kfree(tbl); + retire_sysctl_set(&ns->ipc_set); + return false; + } + + return true; +} + +void retire_ipc_sysctls(struct ipc_namespace *ns) +{ + const struct ctl_table *tbl; + + tbl = ns->ipc_sysctls->ctl_table_arg; + unregister_sysctl_table(ns->ipc_sysctls); + retire_sysctl_set(&ns->ipc_set); + kfree(tbl); +} + +static int __init ipc_sysctl_init(void) +{ + if (!setup_ipc_sysctls(&init_ipc_ns)) { + pr_warn("ipc sysctl registration failed\n"); + return -ENOMEM; + } + return 0; +} + +device_initcall(ipc_sysctl_init); + +static int __init ipc_mni_extend(char *str) +{ + ipc_mni = IPCMNI_EXTEND; + ipc_mni_shift = IPCMNI_EXTEND_SHIFT; + ipc_min_cycle = IPCMNI_EXTEND_MIN_CYCLE; + pr_info("IPCMNI extended to %d.\n", ipc_mni); + return 0; +} +early_param("ipcmni_extend", ipc_mni_extend); |
