rk: printk: add pm_emit_log_char
[firefly-linux-kernel-4.4.55.git] / kernel / sys.c
index fef7bdb1af800c9517b87694bcd53871eb1bcf62..01f195e9607323ac1595e429917b8617fdb727a6 100644 (file)
 #include <linux/ptrace.h>
 #include <linux/fs_struct.h>
 #include <linux/gfp.h>
+#include <linux/syscore_ops.h>
+#include <linux/version.h>
+#include <linux/ctype.h>
 
 #include <linux/compat.h>
 #include <linux/syscalls.h>
 #include <linux/kprobes.h>
 #include <linux/user_namespace.h>
 
+#include <linux/kmsg_dump.h>
+/* Move somewhere else to avoid recompiling? */
+#include <generated/utsrelease.h>
+
 #include <asm/uaccess.h>
 #include <asm/io.h>
 #include <asm/unistd.h>
@@ -128,17 +135,34 @@ EXPORT_SYMBOL(cad_pid);
 
 void (*pm_power_off_prepare)(void);
 
+/*
+ * Returns true if current's euid is same as p's uid or euid,
+ * or has CAP_SYS_NICE to p's user_ns.
+ *
+ * Called with rcu_read_lock, creds are safe
+ */
+static bool set_one_prio_perm(struct task_struct *p)
+{
+       const struct cred *cred = current_cred(), *pcred = __task_cred(p);
+
+       if (pcred->user->user_ns == cred->user->user_ns &&
+           (pcred->uid  == cred->euid ||
+            pcred->euid == cred->euid))
+               return true;
+       if (ns_capable(pcred->user->user_ns, CAP_SYS_NICE))
+               return true;
+       return false;
+}
+
 /*
  * set the priority of a task
  * - the caller must hold the RCU read lock
  */
 static int set_one_prio(struct task_struct *p, int niceval, int error)
 {
-       const struct cred *cred = current_cred(), *pcred = __task_cred(p);
        int no_nice;
 
-       if (pcred->uid  != cred->euid &&
-           pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) {
+       if (!set_one_prio_perm(p)) {
                error = -EPERM;
                goto out;
        }
@@ -297,6 +321,7 @@ out_unlock:
  */
 void emergency_restart(void)
 {
+       kmsg_dump(KMSG_DUMP_EMERG);
        machine_emergency_restart();
 }
 EXPORT_SYMBOL_GPL(emergency_restart);
@@ -305,8 +330,9 @@ void kernel_restart_prepare(char *cmd)
 {
        blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
        system_state = SYSTEM_RESTART;
+       usermodehelper_disable();
        device_shutdown();
-       sysdev_shutdown();
+       syscore_shutdown();
 }
 
 /**
@@ -325,10 +351,12 @@ void kernel_restart(char *cmd)
        restart_dbg("%s->%d->cmd=%s",__FUNCTION__,__LINE__,cmd);
        
        kernel_restart_prepare(cmd);
+       disable_nonboot_cpus();
        if (!cmd)
-               printk( "Restarting system.\n");
+               printk(KERN_EMERG "Restarting system.\n");
        else
-               printk( "Restarting system with command '%s'.\n", cmd);
+               printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd);
+       kmsg_dump(KMSG_DUMP_RESTART);
        machine_restart(cmd);
 }
 EXPORT_SYMBOL_GPL(kernel_restart);
@@ -338,6 +366,7 @@ static void kernel_shutdown_prepare(enum system_states state)
        blocking_notifier_call_chain(&reboot_notifier_list,
                (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);
        system_state = state;
+       usermodehelper_disable();
        device_shutdown();
 }
 /**
@@ -348,8 +377,9 @@ static void kernel_shutdown_prepare(enum system_states state)
 void kernel_halt(void)
 {
        kernel_shutdown_prepare(SYSTEM_HALT);
-       sysdev_shutdown();
+       syscore_shutdown();
        printk(KERN_EMERG "System halted.\n");
+       kmsg_dump(KMSG_DUMP_HALT);
        machine_halt();
 }
 
@@ -366,8 +396,9 @@ void kernel_power_off(void)
        if (pm_power_off_prepare)
                pm_power_off_prepare();
        disable_nonboot_cpus();
-       sysdev_shutdown();
+       syscore_shutdown();
        printk(KERN_EMERG "Power down.\n");
+       kmsg_dump(KMSG_DUMP_POWEROFF);
        machine_power_off();
 }
 EXPORT_SYMBOL_GPL(kernel_power_off);
@@ -527,7 +558,7 @@ SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
        if (rgid != (gid_t) -1) {
                if (old->gid == rgid ||
                    old->egid == rgid ||
-                   capable(CAP_SETGID))
+                   nsown_capable(CAP_SETGID))
                        new->gid = rgid;
                else
                        goto error;
@@ -536,7 +567,7 @@ SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
                if (old->gid == egid ||
                    old->egid == egid ||
                    old->sgid == egid ||
-                   capable(CAP_SETGID))
+                   nsown_capable(CAP_SETGID))
                        new->egid = egid;
                else
                        goto error;
@@ -571,7 +602,7 @@ SYSCALL_DEFINE1(setgid, gid_t, gid)
        old = current_cred();
 
        retval = -EPERM;
-       if (capable(CAP_SETGID))
+       if (nsown_capable(CAP_SETGID))
                new->gid = new->egid = new->sgid = new->fsgid = gid;
        else if (gid == old->gid || gid == old->sgid)
                new->egid = new->fsgid = gid;
@@ -638,7 +669,7 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
                new->uid = ruid;
                if (old->uid != ruid &&
                    old->euid != ruid &&
-                   !capable(CAP_SETUID))
+                   !nsown_capable(CAP_SETUID))
                        goto error;
        }
 
@@ -647,7 +678,7 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
                if (old->uid != euid &&
                    old->euid != euid &&
                    old->suid != euid &&
-                   !capable(CAP_SETUID))
+                   !nsown_capable(CAP_SETUID))
                        goto error;
        }
 
@@ -695,7 +726,7 @@ SYSCALL_DEFINE1(setuid, uid_t, uid)
        old = current_cred();
 
        retval = -EPERM;
-       if (capable(CAP_SETUID)) {
+       if (nsown_capable(CAP_SETUID)) {
                new->suid = new->uid = uid;
                if (uid != old->uid) {
                        retval = set_user(new);
@@ -737,7 +768,7 @@ SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
        old = current_cred();
 
        retval = -EPERM;
-       if (!capable(CAP_SETUID)) {
+       if (!nsown_capable(CAP_SETUID)) {
                if (ruid != (uid_t) -1 && ruid != old->uid &&
                    ruid != old->euid  && ruid != old->suid)
                        goto error;
@@ -801,7 +832,7 @@ SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
        old = current_cred();
 
        retval = -EPERM;
-       if (!capable(CAP_SETGID)) {
+       if (!nsown_capable(CAP_SETGID)) {
                if (rgid != (gid_t) -1 && rgid != old->gid &&
                    rgid != old->egid  && rgid != old->sgid)
                        goto error;
@@ -861,7 +892,7 @@ SYSCALL_DEFINE1(setfsuid, uid_t, uid)
 
        if (uid == old->uid  || uid == old->euid  ||
            uid == old->suid || uid == old->fsuid ||
-           capable(CAP_SETUID)) {
+           nsown_capable(CAP_SETUID)) {
                if (uid != old_fsuid) {
                        new->fsuid = uid;
                        if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
@@ -894,7 +925,7 @@ SYSCALL_DEFINE1(setfsgid, gid_t, gid)
 
        if (gid == old->gid  || gid == old->egid  ||
            gid == old->sgid || gid == old->fsgid ||
-           capable(CAP_SETGID)) {
+           nsown_capable(CAP_SETGID)) {
                if (gid != old_fsgid) {
                        new->fsgid = gid;
                        goto change_okay;
@@ -1111,8 +1142,10 @@ SYSCALL_DEFINE0(setsid)
        err = session;
 out:
        write_unlock_irq(&tasklist_lock);
-       if (err > 0)
+       if (err > 0) {
                proc_sid_connector(group_leader);
+               sched_autogroup_create_attach(group_leader);
+       }
        return err;
 }
 
@@ -1127,6 +1160,36 @@ DECLARE_RWSEM(uts_sem);
 #define override_architecture(name)    0
 #endif
 
+/*
+ * Work around broken programs that cannot handle "Linux 3.0".
+ * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
+ */
+static int override_release(char __user *release, size_t len)
+{
+       int ret = 0;
+
+       if (current->personality & UNAME26) {
+               const char *rest = UTS_RELEASE;
+               char buf[65] = { 0 };
+               int ndots = 0;
+               unsigned v;
+               size_t copy;
+
+               while (*rest) {
+                       if (*rest == '.' && ++ndots >= 3)
+                               break;
+                       if (!isdigit(*rest) && *rest != '.')
+                               break;
+                       rest++;
+               }
+               v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40;
+               copy = clamp_t(size_t, len, 1, sizeof(buf));
+               copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
+               ret = copy_to_user(release, buf, copy + 1);
+       }
+       return ret;
+}
+
 SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
 {
        int errno = 0;
@@ -1136,6 +1199,8 @@ SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
                errno = -EFAULT;
        up_read(&uts_sem);
 
+       if (!errno && override_release(name->release, sizeof(name->release)))
+               errno = -EFAULT;
        if (!errno && override_architecture(name))
                errno = -EFAULT;
        return errno;
@@ -1157,6 +1222,8 @@ SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
                error = -EFAULT;
        up_read(&uts_sem);
 
+       if (!error && override_release(name->release, sizeof(name->release)))
+               error = -EFAULT;
        if (!error && override_architecture(name))
                error = -EFAULT;
        return error;
@@ -1191,6 +1258,8 @@ SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
 
        if (!error && override_architecture(name))
                error = -EFAULT;
+       if (!error && override_release(name->release, sizeof(name->release)))
+               error = -EFAULT;
        return error ? -EFAULT : 0;
 }
 #endif
@@ -1200,8 +1269,9 @@ SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
        int errno;
        char tmp[__NEW_UTS_LEN];
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
                return -EPERM;
+
        if (len < 0 || len > __NEW_UTS_LEN)
                return -EINVAL;
        down_write(&uts_sem);
@@ -1249,7 +1319,7 @@ SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
        int errno;
        char tmp[__NEW_UTS_LEN];
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
                return -EPERM;
        if (len < 0 || len > __NEW_UTS_LEN)
                return -EINVAL;
@@ -1364,6 +1434,8 @@ int do_prlimit(struct task_struct *tsk, unsigned int resource,
        rlim = tsk->signal->rlim + resource;
        task_lock(tsk->group_leader);
        if (new_rlim) {
+               /* Keep the capable check against init_user_ns until
+                  cgroups can contain all limits */
                if (new_rlim->rlim_max > rlim->rlim_max &&
                                !capable(CAP_SYS_RESOURCE))
                        retval = -EPERM;
@@ -1407,18 +1479,22 @@ static int check_prlimit_permission(struct task_struct *task)
 {
        const struct cred *cred = current_cred(), *tcred;
 
-       tcred = __task_cred(task);
-       if ((cred->uid != tcred->euid ||
-            cred->uid != tcred->suid ||
-            cred->uid != tcred->uid  ||
-            cred->gid != tcred->egid ||
-            cred->gid != tcred->sgid ||
-            cred->gid != tcred->gid) &&
-            !capable(CAP_SYS_RESOURCE)) {
-               return -EPERM;
-       }
+       if (current == task)
+               return 0;
 
-       return 0;
+       tcred = __task_cred(task);
+       if (cred->user->user_ns == tcred->user->user_ns &&
+           (cred->uid == tcred->euid &&
+            cred->uid == tcred->suid &&
+            cred->uid == tcred->uid  &&
+            cred->gid == tcred->egid &&
+            cred->gid == tcred->sgid &&
+            cred->gid == tcred->gid))
+               return 0;
+       if (ns_capable(tcred->user->user_ns, CAP_SYS_RESOURCE))
+               return 0;
+
+       return -EPERM;
 }
 
 SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,