Merge tag 'bitmap-for-5.19-rc1' of https://github.com/norov/linux

[linux-block.git] / ipc / ipc_sysctl.c

diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c
index eb7ba8e0a355c88129bc0ddb02b32c63b93160bc..ef313ecfb53a12e4f63be71d5b3f6a05afcb79de 100644 (file)
--- a/ipc/ipc_sysctl.c
+++ b/ipc/ipc_sysctl.c
@@ -68,25 +68,6 @@ static int proc_ipc_sem_dointvec(struct ctl_table *table, int write,
        return ret;
 }
 
-#ifdef CONFIG_CHECKPOINT_RESTORE
-static int proc_ipc_dointvec_minmax_checkpoint_restore(struct ctl_table *table,
-               int write, void *buffer, size_t *lenp, loff_t *ppos)
-{
-       struct ipc_namespace *ns = table->extra1;
-       struct ctl_table ipc_table;
-
-       if (write && !checkpoint_restore_ns_capable(ns->user_ns))
-               return -EPERM;
-
-       memcpy(&ipc_table, table, sizeof(ipc_table));
-
-       ipc_table.extra1 = SYSCTL_ZERO;
-       ipc_table.extra2 = SYSCTL_INT_MAX;
-
-       return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
-}
-#endif
-
 int ipc_mni = IPCMNI;
 int ipc_mni_shift = IPCMNI_SHIFT;
 int ipc_min_cycle = RADIX_TREE_MAP_SIZE;
@@ -172,22 +153,28 @@ static struct ctl_table ipc_sysctls[] = {
                .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           = 0666,
-               .proc_handler   = proc_ipc_dointvec_minmax_checkpoint_restore,
+               .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           = 0666,
-               .proc_handler   = proc_ipc_dointvec_minmax_checkpoint_restore,
+               .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           = 0666,
-               .proc_handler   = proc_ipc_dointvec_minmax_checkpoint_restore,
+               .mode           = 0444,
+               .proc_handler   = proc_dointvec_minmax,
+               .extra1         = SYSCTL_ZERO,
+               .extra2         = SYSCTL_INT_MAX,
        },
 #endif
        {}
@@ -203,8 +190,25 @@ static int set_is_seen(struct ctl_table_set *set)
        return &current->nsproxy->ipc_ns->ipc_set == set;
 }
 
+static int ipc_permissions(struct ctl_table_header *head, struct ctl_table *table)
+{
+       int mode = table->mode;
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+       struct ipc_namespace *ns = current->nsproxy->ipc_ns;
+
+       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(ns->user_ns))
+               mode = 0666;
+#endif
+       return mode;
+}
+
 static struct ctl_table_root set_root = {
        .lookup = set_lookup,
+       .permissions = ipc_permissions,
 };
 
 bool setup_ipc_sysctls(struct ipc_namespace *ns)
@@ -218,45 +222,41 @@ bool setup_ipc_sysctls(struct ipc_namespace *ns)
                int i;
 
                for (i = 0; i < ARRAY_SIZE(ipc_sysctls); i++) {
-                       if (tbl[i].data == &init_ipc_ns.shm_ctlmax) {
+                       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) {
+                       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) {
+                       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) {
+                       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) {
+                       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) {
+                       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) {
+                       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) {
+                       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) {
+                       else if (tbl[i].data == &init_ipc_ns.ids[IPC_SEM_IDS].next_id)
                                tbl[i].data = &ns->ids[IPC_SEM_IDS].next_id;
-                               tbl[i].extra1 = ns;
 
-                       } else if (tbl[i].data == &init_ipc_ns.ids[IPC_MSG_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;
-                               tbl[i].extra1 = ns;
 
-                       } else if (tbl[i].data == &init_ipc_ns.ids[IPC_SHM_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;
-                               tbl[i].extra1 = ns;
 #endif
-                       } else {
+                       else
                                tbl[i].data = NULL;
-                       }
                }
 
                ns->ipc_sysctls = __register_sysctl_table(&ns->ipc_set, "kernel", tbl);