| /* |
| * linux/kernel/sys.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <linux/utsname.h> |
| #include <linux/mman.h> |
| #include <linux/smp_lock.h> |
| #include <linux/notifier.h> |
| #include <linux/reboot.h> |
| #include <linux/prctl.h> |
| #include <linux/init.h> |
| #include <linux/highuid.h> |
| #include <linux/fs.h> |
| #include <linux/workqueue.h> |
| #include <linux/device.h> |
| #include <linux/times.h> |
| #include <linux/security.h> |
| #include <linux/dcookies.h> |
| #include <linux/suspend.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/io.h> |
| #include <asm/unistd.h> |
| |
| #ifndef SET_UNALIGN_CTL |
| # define SET_UNALIGN_CTL(a,b) (-EINVAL) |
| #endif |
| #ifndef GET_UNALIGN_CTL |
| # define GET_UNALIGN_CTL(a,b) (-EINVAL) |
| #endif |
| #ifndef SET_FPEMU_CTL |
| # define SET_FPEMU_CTL(a,b) (-EINVAL) |
| #endif |
| #ifndef GET_FPEMU_CTL |
| # define GET_FPEMU_CTL(a,b) (-EINVAL) |
| #endif |
| #ifndef SET_FPEXC_CTL |
| # define SET_FPEXC_CTL(a,b) (-EINVAL) |
| #endif |
| #ifndef GET_FPEXC_CTL |
| # define GET_FPEXC_CTL(a,b) (-EINVAL) |
| #endif |
| |
| /* |
| * this is where the system-wide overflow UID and GID are defined, for |
| * architectures that now have 32-bit UID/GID but didn't in the past |
| */ |
| |
| int overflowuid = DEFAULT_OVERFLOWUID; |
| int overflowgid = DEFAULT_OVERFLOWGID; |
| |
| /* |
| * the same as above, but for filesystems which can only store a 16-bit |
| * UID and GID. as such, this is needed on all architectures |
| */ |
| |
| int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; |
| int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; |
| |
| /* |
| * this indicates whether you can reboot with ctrl-alt-del: the default is yes |
| */ |
| |
| int C_A_D = 1; |
| int cad_pid = 1; |
| |
| extern int system_running; |
| |
| /* |
| * Notifier list for kernel code which wants to be called |
| * at shutdown. This is used to stop any idling DMA operations |
| * and the like. |
| */ |
| |
| static struct notifier_block *reboot_notifier_list; |
| rwlock_t notifier_lock = RW_LOCK_UNLOCKED; |
| |
| /** |
| * notifier_chain_register - Add notifier to a notifier chain |
| * @list: Pointer to root list pointer |
| * @n: New entry in notifier chain |
| * |
| * Adds a notifier to a notifier chain. |
| * |
| * Currently always returns zero. |
| */ |
| |
| int notifier_chain_register(struct notifier_block **list, struct notifier_block *n) |
| { |
| write_lock(¬ifier_lock); |
| while(*list) |
| { |
| if(n->priority > (*list)->priority) |
| break; |
| list= &((*list)->next); |
| } |
| n->next = *list; |
| *list=n; |
| write_unlock(¬ifier_lock); |
| return 0; |
| } |
| |
| /** |
| * notifier_chain_unregister - Remove notifier from a notifier chain |
| * @nl: Pointer to root list pointer |
| * @n: New entry in notifier chain |
| * |
| * Removes a notifier from a notifier chain. |
| * |
| * Returns zero on success, or %-ENOENT on failure. |
| */ |
| |
| int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n) |
| { |
| write_lock(¬ifier_lock); |
| while((*nl)!=NULL) |
| { |
| if((*nl)==n) |
| { |
| *nl=n->next; |
| write_unlock(¬ifier_lock); |
| return 0; |
| } |
| nl=&((*nl)->next); |
| } |
| write_unlock(¬ifier_lock); |
| return -ENOENT; |
| } |
| |
| /** |
| * notifier_call_chain - Call functions in a notifier chain |
| * @n: Pointer to root pointer of notifier chain |
| * @val: Value passed unmodified to notifier function |
| * @v: Pointer passed unmodified to notifier function |
| * |
| * Calls each function in a notifier chain in turn. |
| * |
| * If the return value of the notifier can be and'd |
| * with %NOTIFY_STOP_MASK, then notifier_call_chain |
| * will return immediately, with the return value of |
| * the notifier function which halted execution. |
| * Otherwise, the return value is the return value |
| * of the last notifier function called. |
| */ |
| |
| int notifier_call_chain(struct notifier_block **n, unsigned long val, void *v) |
| { |
| int ret=NOTIFY_DONE; |
| struct notifier_block *nb = *n; |
| |
| while(nb) |
| { |
| ret=nb->notifier_call(nb,val,v); |
| if(ret&NOTIFY_STOP_MASK) |
| { |
| return ret; |
| } |
| nb=nb->next; |
| } |
| return ret; |
| } |
| |
| /** |
| * register_reboot_notifier - Register function to be called at reboot time |
| * @nb: Info about notifier function to be called |
| * |
| * Registers a function with the list of functions |
| * to be called at reboot time. |
| * |
| * Currently always returns zero, as notifier_chain_register |
| * always returns zero. |
| */ |
| |
| int register_reboot_notifier(struct notifier_block * nb) |
| { |
| return notifier_chain_register(&reboot_notifier_list, nb); |
| } |
| |
| /** |
| * unregister_reboot_notifier - Unregister previously registered reboot notifier |
| * @nb: Hook to be unregistered |
| * |
| * Unregisters a previously registered reboot |
| * notifier function. |
| * |
| * Returns zero on success, or %-ENOENT on failure. |
| */ |
| |
| int unregister_reboot_notifier(struct notifier_block * nb) |
| { |
| return notifier_chain_unregister(&reboot_notifier_list, nb); |
| } |
| |
| asmlinkage long sys_ni_syscall(void) |
| { |
| return -ENOSYS; |
| } |
| |
| cond_syscall(sys_nfsservctl) |
| cond_syscall(sys_quotactl) |
| cond_syscall(sys_acct) |
| cond_syscall(sys_lookup_dcookie) |
| cond_syscall(sys_swapon) |
| cond_syscall(sys_swapoff) |
| cond_syscall(sys_init_module) |
| cond_syscall(sys_delete_module) |
| |
| static int set_one_prio(struct task_struct *p, int niceval, int error) |
| { |
| if (p->uid != current->euid && |
| p->uid != current->uid && !capable(CAP_SYS_NICE)) { |
| error = -EPERM; |
| goto out; |
| } |
| |
| if (error == -ESRCH) |
| error = 0; |
| if (niceval < task_nice(p) && !capable(CAP_SYS_NICE)) |
| error = -EACCES; |
| else |
| set_user_nice(p, niceval); |
| out: |
| return error; |
| } |
| |
| asmlinkage long sys_setpriority(int which, int who, int niceval) |
| { |
| struct task_struct *g, *p; |
| struct user_struct *user; |
| struct pid *pid; |
| struct list_head *l; |
| int error = -EINVAL; |
| |
| if (which > 2 || which < 0) |
| goto out; |
| |
| /* normalize: avoid signed division (rounding problems) */ |
| error = -ESRCH; |
| if (niceval < -20) |
| niceval = -20; |
| if (niceval > 19) |
| niceval = 19; |
| |
| read_lock(&tasklist_lock); |
| switch (which) { |
| case PRIO_PROCESS: |
| if (!who) |
| who = current->pid; |
| p = find_task_by_pid(who); |
| if (p) |
| error = set_one_prio(p, niceval, error); |
| break; |
| case PRIO_PGRP: |
| if (!who) |
| who = current->pgrp; |
| for_each_task_pid(who, PIDTYPE_PGID, p, l, pid) |
| error = set_one_prio(p, niceval, error); |
| break; |
| case PRIO_USER: |
| if (!who) |
| user = current->user; |
| else |
| user = find_user(who); |
| |
| if (!user) |
| goto out_unlock; |
| |
| do_each_thread(g, p) |
| if (p->uid == who) |
| error = set_one_prio(p, niceval, error); |
| while_each_thread(g, p); |
| break; |
| } |
| out_unlock: |
| read_unlock(&tasklist_lock); |
| out: |
| return error; |
| } |
| |
| /* |
| * Ugh. To avoid negative return values, "getpriority()" will |
| * not return the normal nice-value, but a negated value that |
| * has been offset by 20 (ie it returns 40..1 instead of -20..19) |
| * to stay compatible. |
| */ |
| asmlinkage long sys_getpriority(int which, int who) |
| { |
| struct task_struct *g, *p; |
| struct list_head *l; |
| struct pid *pid; |
| struct user_struct *user; |
| long niceval, retval = -ESRCH; |
| |
| if (which > 2 || which < 0) |
| return -EINVAL; |
| |
| read_lock(&tasklist_lock); |
| switch (which) { |
| case PRIO_PROCESS: |
| if (!who) |
| who = current->pid; |
| p = find_task_by_pid(who); |
| if (p) { |
| niceval = 20 - task_nice(p); |
| if (niceval > retval) |
| retval = niceval; |
| } |
| break; |
| case PRIO_PGRP: |
| if (!who) |
| who = current->pgrp; |
| for_each_task_pid(who, PIDTYPE_PGID, p, l, pid) { |
| niceval = 20 - task_nice(p); |
| if (niceval > retval) |
| retval = niceval; |
| } |
| break; |
| case PRIO_USER: |
| if (!who) |
| user = current->user; |
| else |
| user = find_user(who); |
| |
| if (!user) |
| goto out_unlock; |
| |
| do_each_thread(g, p) |
| if (p->uid == who) { |
| niceval = 20 - task_nice(p); |
| if (niceval > retval) |
| retval = niceval; |
| } |
| while_each_thread(g, p); |
| break; |
| } |
| out_unlock: |
| read_unlock(&tasklist_lock); |
| |
| return retval; |
| } |
| |
| |
| /* |
| * Reboot system call: for obvious reasons only root may call it, |
| * and even root needs to set up some magic numbers in the registers |
| * so that some mistake won't make this reboot the whole machine. |
| * You can also set the meaning of the ctrl-alt-del-key here. |
| * |
| * reboot doesn't sync: do that yourself before calling this. |
| */ |
| asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void * arg) |
| { |
| char buffer[256]; |
| |
| /* We only trust the superuser with rebooting the system. */ |
| if (!capable(CAP_SYS_BOOT)) |
| return -EPERM; |
| |
| /* For safety, we require "magic" arguments. */ |
| if (magic1 != LINUX_REBOOT_MAGIC1 || |
| (magic2 != LINUX_REBOOT_MAGIC2 && magic2 != LINUX_REBOOT_MAGIC2A && |
| magic2 != LINUX_REBOOT_MAGIC2B)) |
| return -EINVAL; |
| |
| lock_kernel(); |
| switch (cmd) { |
| case LINUX_REBOOT_CMD_RESTART: |
| notifier_call_chain(&reboot_notifier_list, SYS_RESTART, NULL); |
| system_running = 0; |
| device_shutdown(); |
| printk(KERN_EMERG "Restarting system.\n"); |
| machine_restart(NULL); |
| break; |
| |
| case LINUX_REBOOT_CMD_CAD_ON: |
| C_A_D = 1; |
| break; |
| |
| case LINUX_REBOOT_CMD_CAD_OFF: |
| C_A_D = 0; |
| break; |
| |
| case LINUX_REBOOT_CMD_HALT: |
| notifier_call_chain(&reboot_notifier_list, SYS_HALT, NULL); |
| system_running = 0; |
| device_shutdown(); |
| printk(KERN_EMERG "System halted.\n"); |
| machine_halt(); |
| unlock_kernel(); |
| do_exit(0); |
| break; |
| |
| case LINUX_REBOOT_CMD_POWER_OFF: |
| notifier_call_chain(&reboot_notifier_list, SYS_POWER_OFF, NULL); |
| system_running = 0; |
| device_shutdown(); |
| printk(KERN_EMERG "Power down.\n"); |
| machine_power_off(); |
| unlock_kernel(); |
| do_exit(0); |
| break; |
| |
| case LINUX_REBOOT_CMD_RESTART2: |
| if (strncpy_from_user(&buffer[0], (char *)arg, sizeof(buffer) - 1) < 0) { |
| unlock_kernel(); |
| return -EFAULT; |
| } |
| buffer[sizeof(buffer) - 1] = '\0'; |
| |
| notifier_call_chain(&reboot_notifier_list, SYS_RESTART, buffer); |
| system_running = 0; |
| device_shutdown(); |
| printk(KERN_EMERG "Restarting system with command '%s'.\n", buffer); |
| machine_restart(buffer); |
| break; |
| |
| #ifdef CONFIG_SOFTWARE_SUSPEND |
| case LINUX_REBOOT_CMD_SW_SUSPEND: |
| if (!software_suspend_enabled) { |
| unlock_kernel(); |
| return -EAGAIN; |
| } |
| software_suspend(); |
| do_exit(0); |
| break; |
| #endif |
| |
| default: |
| unlock_kernel(); |
| return -EINVAL; |
| } |
| unlock_kernel(); |
| return 0; |
| } |
| |
| static void deferred_cad(void *dummy) |
| { |
| notifier_call_chain(&reboot_notifier_list, SYS_RESTART, NULL); |
| machine_restart(NULL); |
| } |
| |
| /* |
| * This function gets called by ctrl-alt-del - ie the keyboard interrupt. |
| * As it's called within an interrupt, it may NOT sync: the only choice |
| * is whether to reboot at once, or just ignore the ctrl-alt-del. |
| */ |
| void ctrl_alt_del(void) |
| { |
| static DECLARE_WORK(cad_work, deferred_cad, NULL); |
| |
| if (C_A_D) |
| schedule_work(&cad_work); |
| else |
| kill_proc(cad_pid, SIGINT, 1); |
| } |
| |
| |
| /* |
| * Unprivileged users may change the real gid to the effective gid |
| * or vice versa. (BSD-style) |
| * |
| * If you set the real gid at all, or set the effective gid to a value not |
| * equal to the real gid, then the saved gid is set to the new effective gid. |
| * |
| * This makes it possible for a setgid program to completely drop its |
| * privileges, which is often a useful assertion to make when you are doing |
| * a security audit over a program. |
| * |
| * The general idea is that a program which uses just setregid() will be |
| * 100% compatible with BSD. A program which uses just setgid() will be |
| * 100% compatible with POSIX with saved IDs. |
| * |
| * SMP: There are not races, the GIDs are checked only by filesystem |
| * operations (as far as semantic preservation is concerned). |
| */ |
| asmlinkage long sys_setregid(gid_t rgid, gid_t egid) |
| { |
| int old_rgid = current->gid; |
| int old_egid = current->egid; |
| int new_rgid = old_rgid; |
| int new_egid = old_egid; |
| int retval; |
| |
| retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
| if (retval) |
| return retval; |
| |
| if (rgid != (gid_t) -1) { |
| if ((old_rgid == rgid) || |
| (current->egid==rgid) || |
| capable(CAP_SETGID)) |
| new_rgid = rgid; |
| else |
| return -EPERM; |
| } |
| if (egid != (gid_t) -1) { |
| if ((old_rgid == egid) || |
| (current->egid == egid) || |
| (current->sgid == egid) || |
| capable(CAP_SETGID)) |
| new_egid = egid; |
| else { |
| return -EPERM; |
| } |
| } |
| if (new_egid != old_egid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| if (rgid != (gid_t) -1 || |
| (egid != (gid_t) -1 && egid != old_rgid)) |
| current->sgid = new_egid; |
| current->fsgid = new_egid; |
| current->egid = new_egid; |
| current->gid = new_rgid; |
| return 0; |
| } |
| |
| /* |
| * setgid() is implemented like SysV w/ SAVED_IDS |
| * |
| * SMP: Same implicit races as above. |
| */ |
| asmlinkage long sys_setgid(gid_t gid) |
| { |
| int old_egid = current->egid; |
| int retval; |
| |
| retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
| if (retval) |
| return retval; |
| |
| if (capable(CAP_SETGID)) |
| { |
| if(old_egid != gid) |
| { |
| current->mm->dumpable=0; |
| wmb(); |
| } |
| current->gid = current->egid = current->sgid = current->fsgid = gid; |
| } |
| else if ((gid == current->gid) || (gid == current->sgid)) |
| { |
| if(old_egid != gid) |
| { |
| current->mm->dumpable=0; |
| wmb(); |
| } |
| current->egid = current->fsgid = gid; |
| } |
| else |
| return -EPERM; |
| return 0; |
| } |
| |
| static int set_user(uid_t new_ruid, int dumpclear) |
| { |
| struct user_struct *new_user; |
| |
| new_user = alloc_uid(new_ruid); |
| if (!new_user) |
| return -EAGAIN; |
| switch_uid(new_user); |
| |
| if(dumpclear) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->uid = new_ruid; |
| return 0; |
| } |
| |
| /* |
| * Unprivileged users may change the real uid to the effective uid |
| * or vice versa. (BSD-style) |
| * |
| * If you set the real uid at all, or set the effective uid to a value not |
| * equal to the real uid, then the saved uid is set to the new effective uid. |
| * |
| * This makes it possible for a setuid program to completely drop its |
| * privileges, which is often a useful assertion to make when you are doing |
| * a security audit over a program. |
| * |
| * The general idea is that a program which uses just setreuid() will be |
| * 100% compatible with BSD. A program which uses just setuid() will be |
| * 100% compatible with POSIX with saved IDs. |
| */ |
| asmlinkage long sys_setreuid(uid_t ruid, uid_t euid) |
| { |
| int old_ruid, old_euid, old_suid, new_ruid, new_euid; |
| int retval; |
| |
| retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); |
| if (retval) |
| return retval; |
| |
| new_ruid = old_ruid = current->uid; |
| new_euid = old_euid = current->euid; |
| old_suid = current->suid; |
| |
| if (ruid != (uid_t) -1) { |
| new_ruid = ruid; |
| if ((old_ruid != ruid) && |
| (current->euid != ruid) && |
| !capable(CAP_SETUID)) |
| return -EPERM; |
| } |
| |
| if (euid != (uid_t) -1) { |
| new_euid = euid; |
| if ((old_ruid != euid) && |
| (current->euid != euid) && |
| (current->suid != euid) && |
| !capable(CAP_SETUID)) |
| return -EPERM; |
| } |
| |
| if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0) |
| return -EAGAIN; |
| |
| if (new_euid != old_euid) |
| { |
| current->mm->dumpable=0; |
| wmb(); |
| } |
| current->fsuid = current->euid = new_euid; |
| if (ruid != (uid_t) -1 || |
| (euid != (uid_t) -1 && euid != old_ruid)) |
| current->suid = current->euid; |
| current->fsuid = current->euid; |
| |
| return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE); |
| } |
| |
| |
| |
| /* |
| * setuid() is implemented like SysV with SAVED_IDS |
| * |
| * Note that SAVED_ID's is deficient in that a setuid root program |
| * like sendmail, for example, cannot set its uid to be a normal |
| * user and then switch back, because if you're root, setuid() sets |
| * the saved uid too. If you don't like this, blame the bright people |
| * in the POSIX committee and/or USG. Note that the BSD-style setreuid() |
| * will allow a root program to temporarily drop privileges and be able to |
| * regain them by swapping the real and effective uid. |
| */ |
| asmlinkage long sys_setuid(uid_t uid) |
| { |
| int old_euid = current->euid; |
| int old_ruid, old_suid, new_ruid, new_suid; |
| int retval; |
| |
| retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
| if (retval) |
| return retval; |
| |
| old_ruid = new_ruid = current->uid; |
| old_suid = current->suid; |
| new_suid = old_suid; |
| |
| if (capable(CAP_SETUID)) { |
| if (uid != old_ruid && set_user(uid, old_euid != uid) < 0) |
| return -EAGAIN; |
| new_suid = uid; |
| } else if ((uid != current->uid) && (uid != new_suid)) |
| return -EPERM; |
| |
| if (old_euid != uid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->fsuid = current->euid = uid; |
| current->suid = new_suid; |
| |
| return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID); |
| } |
| |
| |
| /* |
| * This function implements a generic ability to update ruid, euid, |
| * and suid. This allows you to implement the 4.4 compatible seteuid(). |
| */ |
| asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) |
| { |
| int old_ruid = current->uid; |
| int old_euid = current->euid; |
| int old_suid = current->suid; |
| int retval; |
| |
| retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
| if (retval) |
| return retval; |
| |
| if (!capable(CAP_SETUID)) { |
| if ((ruid != (uid_t) -1) && (ruid != current->uid) && |
| (ruid != current->euid) && (ruid != current->suid)) |
| return -EPERM; |
| if ((euid != (uid_t) -1) && (euid != current->uid) && |
| (euid != current->euid) && (euid != current->suid)) |
| return -EPERM; |
| if ((suid != (uid_t) -1) && (suid != current->uid) && |
| (suid != current->euid) && (suid != current->suid)) |
| return -EPERM; |
| } |
| if (ruid != (uid_t) -1) { |
| if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0) |
| return -EAGAIN; |
| } |
| if (euid != (uid_t) -1) { |
| if (euid != current->euid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->euid = euid; |
| } |
| current->fsuid = current->euid; |
| if (suid != (uid_t) -1) |
| current->suid = suid; |
| |
| return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES); |
| } |
| |
| asmlinkage long sys_getresuid(uid_t *ruid, uid_t *euid, uid_t *suid) |
| { |
| int retval; |
| |
| if (!(retval = put_user(current->uid, ruid)) && |
| !(retval = put_user(current->euid, euid))) |
| retval = put_user(current->suid, suid); |
| |
| return retval; |
| } |
| |
| /* |
| * Same as above, but for rgid, egid, sgid. |
| */ |
| asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) |
| { |
| int retval; |
| |
| retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
| if (retval) |
| return retval; |
| |
| if (!capable(CAP_SETGID)) { |
| if ((rgid != (gid_t) -1) && (rgid != current->gid) && |
| (rgid != current->egid) && (rgid != current->sgid)) |
| return -EPERM; |
| if ((egid != (gid_t) -1) && (egid != current->gid) && |
| (egid != current->egid) && (egid != current->sgid)) |
| return -EPERM; |
| if ((sgid != (gid_t) -1) && (sgid != current->gid) && |
| (sgid != current->egid) && (sgid != current->sgid)) |
| return -EPERM; |
| } |
| if (egid != (gid_t) -1) { |
| if (egid != current->egid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->egid = egid; |
| } |
| current->fsgid = current->egid; |
| if (rgid != (gid_t) -1) |
| current->gid = rgid; |
| if (sgid != (gid_t) -1) |
| current->sgid = sgid; |
| return 0; |
| } |
| |
| asmlinkage long sys_getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid) |
| { |
| int retval; |
| |
| if (!(retval = put_user(current->gid, rgid)) && |
| !(retval = put_user(current->egid, egid))) |
| retval = put_user(current->sgid, sgid); |
| |
| return retval; |
| } |
| |
| |
| /* |
| * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This |
| * is used for "access()" and for the NFS daemon (letting nfsd stay at |
| * whatever uid it wants to). It normally shadows "euid", except when |
| * explicitly set by setfsuid() or for access.. |
| */ |
| asmlinkage long sys_setfsuid(uid_t uid) |
| { |
| int old_fsuid; |
| int retval; |
| |
| retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS); |
| if (retval) |
| return retval; |
| |
| old_fsuid = current->fsuid; |
| if (uid == current->uid || uid == current->euid || |
| uid == current->suid || uid == current->fsuid || |
| capable(CAP_SETUID)) |
| { |
| if (uid != old_fsuid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->fsuid = uid; |
| } |
| |
| retval = security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS); |
| if (retval) |
| return retval; |
| |
| return old_fsuid; |
| } |
| |
| /* |
| * Samma på svenska.. |
| */ |
| asmlinkage long sys_setfsgid(gid_t gid) |
| { |
| int old_fsgid; |
| int retval; |
| |
| retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS); |
| if (retval) |
| return retval; |
| |
| old_fsgid = current->fsgid; |
| if (gid == current->gid || gid == current->egid || |
| gid == current->sgid || gid == current->fsgid || |
| capable(CAP_SETGID)) |
| { |
| if (gid != old_fsgid) |
| { |
| current->mm->dumpable = 0; |
| wmb(); |
| } |
| current->fsgid = gid; |
| } |
| return old_fsgid; |
| } |
| |
| asmlinkage long sys_times(struct tms * tbuf) |
| { |
| /* |
| * In the SMP world we might just be unlucky and have one of |
| * the times increment as we use it. Since the value is an |
| * atomically safe type this is just fine. Conceptually its |
| * as if the syscall took an instant longer to occur. |
| */ |
| if (tbuf) { |
| struct tms tmp; |
| tmp.tms_utime = jiffies_to_clock_t(current->utime); |
| tmp.tms_stime = jiffies_to_clock_t(current->stime); |
| tmp.tms_cutime = jiffies_to_clock_t(current->cutime); |
| tmp.tms_cstime = jiffies_to_clock_t(current->cstime); |
| if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
| return -EFAULT; |
| } |
| return jiffies_to_clock_t(jiffies); |
| } |
| |
| /* |
| * This needs some heavy checking ... |
| * I just haven't the stomach for it. I also don't fully |
| * understand sessions/pgrp etc. Let somebody who does explain it. |
| * |
| * OK, I think I have the protection semantics right.... this is really |
| * only important on a multi-user system anyway, to make sure one user |
| * can't send a signal to a process owned by another. -TYT, 12/12/91 |
| * |
| * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. |
| * LBT 04.03.94 |
| */ |
| |
| asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) |
| { |
| struct task_struct *p; |
| int err = -EINVAL; |
| |
| if (!pid) |
| pid = current->pid; |
| if (!pgid) |
| pgid = pid; |
| if (pgid < 0) |
| return -EINVAL; |
| |
| /* From this point forward we keep holding onto the tasklist lock |
| * so that our parent does not change from under us. -DaveM |
| */ |
| write_lock_irq(&tasklist_lock); |
| |
| err = -ESRCH; |
| p = find_task_by_pid(pid); |
| if (!p) |
| goto out; |
| |
| err = -EINVAL; |
| if (!thread_group_leader(p)) |
| goto out; |
| |
| if (p->parent == current || p->real_parent == current) { |
| err = -EPERM; |
| if (p->session != current->session) |
| goto out; |
| err = -EACCES; |
| if (p->did_exec) |
| goto out; |
| } else { |
| err = -ESRCH; |
| if (p != current) |
| goto out; |
| } |
| |
| err = -EPERM; |
| if (p->leader) |
| goto out; |
| |
| if (pgid != pid) { |
| struct task_struct *p; |
| struct pid *pid; |
| struct list_head *l; |
| |
| for_each_task_pid(pgid, PIDTYPE_PGID, p, l, pid) |
| if (p->session == current->session) |
| goto ok_pgid; |
| goto out; |
| } |
| |
| ok_pgid: |
| if (p->pgrp != pgid) { |
| detach_pid(p, PIDTYPE_PGID); |
| p->pgrp = pgid; |
| attach_pid(p, PIDTYPE_PGID, pgid); |
| } |
| err = 0; |
| out: |
| /* All paths lead to here, thus we are safe. -DaveM */ |
| write_unlock_irq(&tasklist_lock); |
| return err; |
| } |
| |
| asmlinkage long sys_getpgid(pid_t pid) |
| { |
| if (!pid) { |
| return current->pgrp; |
| } else { |
| int retval; |
| struct task_struct *p; |
| |
| read_lock(&tasklist_lock); |
| p = find_task_by_pid(pid); |
| |
| retval = -ESRCH; |
| if (p) { |
| retval = security_task_getpgid(p); |
| if (!retval) |
| retval = p->pgrp; |
| } |
| read_unlock(&tasklist_lock); |
| return retval; |
| } |
| } |
| |
| asmlinkage long sys_getpgrp(void) |
| { |
| /* SMP - assuming writes are word atomic this is fine */ |
| return current->pgrp; |
| } |
| |
| asmlinkage long sys_getsid(pid_t pid) |
| { |
| if (!pid) { |
| return current->session; |
| } else { |
| int retval; |
| struct task_struct *p; |
| |
| read_lock(&tasklist_lock); |
| p = find_task_by_pid(pid); |
| |
| retval = -ESRCH; |
| if(p) { |
| retval = security_task_getsid(p); |
| if (!retval) |
| retval = p->session; |
| } |
| read_unlock(&tasklist_lock); |
| return retval; |
| } |
| } |
| |
| asmlinkage long sys_setsid(void) |
| { |
| struct pid *pid; |
| int err = -EPERM; |
| |
| if (!thread_group_leader(current)) |
| return -EINVAL; |
| |
| write_lock_irq(&tasklist_lock); |
| |
| pid = find_pid(PIDTYPE_PGID, current->pid); |
| if (pid) |
| goto out; |
| |
| current->leader = 1; |
| __set_special_pids(current->pid, current->pid); |
| current->tty = NULL; |
| current->tty_old_pgrp = 0; |
| err = current->pgrp; |
| out: |
| write_unlock_irq(&tasklist_lock); |
| return err; |
| } |
| |
| /* |
| * Supplementary group IDs |
| */ |
| asmlinkage long sys_getgroups(int gidsetsize, gid_t *grouplist) |
| { |
| int i; |
| |
| /* |
| * SMP: Nobody else can change our grouplist. Thus we are |
| * safe. |
| */ |
| |
| if (gidsetsize < 0) |
| return -EINVAL; |
| i = current->ngroups; |
| if (gidsetsize) { |
| if (i > gidsetsize) |
| return -EINVAL; |
| if (copy_to_user(grouplist, current->groups, sizeof(gid_t)*i)) |
| return -EFAULT; |
| } |
| return i; |
| } |
| |
| /* |
| * SMP: Our groups are not shared. We can copy to/from them safely |
| * without another task interfering. |
| */ |
| |
| asmlinkage long sys_setgroups(int gidsetsize, gid_t *grouplist) |
| { |
| gid_t groups[NGROUPS]; |
| int retval; |
| |
| if (!capable(CAP_SETGID)) |
| return -EPERM; |
| if ((unsigned) gidsetsize > NGROUPS) |
| return -EINVAL; |
| if(copy_from_user(groups, grouplist, gidsetsize * sizeof(gid_t))) |
| return -EFAULT; |
| retval = security_task_setgroups(gidsetsize, groups); |
| if (retval) |
| return retval; |
| memcpy(current->groups, groups, gidsetsize * sizeof(gid_t)); |
| current->ngroups = gidsetsize; |
| return 0; |
| } |
| |
| static int supplemental_group_member(gid_t grp) |
| { |
| int i = current->ngroups; |
| |
| if (i) { |
| gid_t *groups = current->groups; |
| do { |
| if (*groups == grp) |
| return 1; |
| groups++; |
| i--; |
| } while (i); |
| } |
| return 0; |
| } |
| |
| /* |
| * Check whether we're fsgid/egid or in the supplemental group.. |
| */ |
| int in_group_p(gid_t grp) |
| { |
| int retval = 1; |
| if (grp != current->fsgid) |
| retval = supplemental_group_member(grp); |
| return retval; |
| } |
| |
| int in_egroup_p(gid_t grp) |
| { |
| int retval = 1; |
| if (grp != current->egid) |
| retval = supplemental_group_member(grp); |
| return retval; |
| } |
| |
| DECLARE_RWSEM(uts_sem); |
| |
| asmlinkage long sys_newuname(struct new_utsname * name) |
| { |
| int errno = 0; |
| |
| down_read(&uts_sem); |
| if (copy_to_user(name,&system_utsname,sizeof *name)) |
| errno = -EFAULT; |
| up_read(&uts_sem); |
| return errno; |
| } |
| |
| asmlinkage long sys_sethostname(char *name, int len) |
| { |
| int errno; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| if (len < 0 || len > __NEW_UTS_LEN) |
| return -EINVAL; |
| down_write(&uts_sem); |
| errno = -EFAULT; |
| if (!copy_from_user(system_utsname.nodename, name, len)) { |
| system_utsname.nodename[len] = 0; |
| errno = 0; |
| } |
| up_write(&uts_sem); |
| return errno; |
| } |
| |
| asmlinkage long sys_gethostname(char *name, int len) |
| { |
| int i, errno; |
| |
| if (len < 0) |
| return -EINVAL; |
| down_read(&uts_sem); |
| i = 1 + strlen(system_utsname.nodename); |
| if (i > len) |
| i = len; |
| errno = 0; |
| if (copy_to_user(name, system_utsname.nodename, i)) |
| errno = -EFAULT; |
| up_read(&uts_sem); |
| return errno; |
| } |
| |
| /* |
| * Only setdomainname; getdomainname can be implemented by calling |
| * uname() |
| */ |
| asmlinkage long sys_setdomainname(char *name, int len) |
| { |
| int errno; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| if (len < 0 || len > __NEW_UTS_LEN) |
| return -EINVAL; |
| |
| down_write(&uts_sem); |
| errno = -EFAULT; |
| if (!copy_from_user(system_utsname.domainname, name, len)) { |
| errno = 0; |
| system_utsname.domainname[len] = 0; |
| } |
| up_write(&uts_sem); |
| return errno; |
| } |
| |
| asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit *rlim) |
| { |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| else |
| return copy_to_user(rlim, current->rlim + resource, sizeof(*rlim)) |
| ? -EFAULT : 0; |
| } |
| |
| #if !defined(__ia64__) && !defined(CONFIG_V850) |
| |
| /* |
| * Back compatibility for getrlimit. Needed for some apps. |
| */ |
| |
| asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit *rlim) |
| { |
| struct rlimit x; |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| |
| memcpy(&x, current->rlim + resource, sizeof(*rlim)); |
| if(x.rlim_cur > 0x7FFFFFFF) |
| x.rlim_cur = 0x7FFFFFFF; |
| if(x.rlim_max > 0x7FFFFFFF) |
| x.rlim_max = 0x7FFFFFFF; |
| return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; |
| } |
| |
| #endif |
| |
| asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit *rlim) |
| { |
| struct rlimit new_rlim, *old_rlim; |
| int retval; |
| |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| if(copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
| return -EFAULT; |
| if (new_rlim.rlim_cur > new_rlim.rlim_max) |
| return -EINVAL; |
| old_rlim = current->rlim + resource; |
| if (((new_rlim.rlim_cur > old_rlim->rlim_max) || |
| (new_rlim.rlim_max > old_rlim->rlim_max)) && |
| !capable(CAP_SYS_RESOURCE)) |
| return -EPERM; |
| if (resource == RLIMIT_NOFILE) { |
| if (new_rlim.rlim_cur > NR_OPEN || new_rlim.rlim_max > NR_OPEN) |
| return -EPERM; |
| } |
| |
| retval = security_task_setrlimit(resource, &new_rlim); |
| if (retval) |
| return retval; |
| |
| *old_rlim = new_rlim; |
| return 0; |
| } |
| |
| /* |
| * It would make sense to put struct rusage in the task_struct, |
| * except that would make the task_struct be *really big*. After |
| * task_struct gets moved into malloc'ed memory, it would |
| * make sense to do this. It will make moving the rest of the information |
| * a lot simpler! (Which we're not doing right now because we're not |
| * measuring them yet). |
| * |
| * This is SMP safe. Either we are called from sys_getrusage on ourselves |
| * below (we know we aren't going to exit/disappear and only we change our |
| * rusage counters), or we are called from wait4() on a process which is |
| * either stopped or zombied. In the zombied case the task won't get |
| * reaped till shortly after the call to getrusage(), in both cases the |
| * task being examined is in a frozen state so the counters won't change. |
| * |
| * FIXME! Get the fault counts properly! |
| */ |
| int getrusage(struct task_struct *p, int who, struct rusage *ru) |
| { |
| struct rusage r; |
| |
| memset((char *) &r, 0, sizeof(r)); |
| switch (who) { |
| case RUSAGE_SELF: |
| jiffies_to_timeval(p->utime, &r.ru_utime); |
| jiffies_to_timeval(p->stime, &r.ru_stime); |
| r.ru_minflt = p->min_flt; |
| r.ru_majflt = p->maj_flt; |
| r.ru_nswap = p->nswap; |
| break; |
| case RUSAGE_CHILDREN: |
| jiffies_to_timeval(p->cutime, &r.ru_utime); |
| jiffies_to_timeval(p->cstime, &r.ru_stime); |
| r.ru_minflt = p->cmin_flt; |
| r.ru_majflt = p->cmaj_flt; |
| r.ru_nswap = p->cnswap; |
| break; |
| default: |
| jiffies_to_timeval(p->utime + p->cutime, &r.ru_utime); |
| jiffies_to_timeval(p->stime + p->cstime, &r.ru_stime); |
| r.ru_minflt = p->min_flt + p->cmin_flt; |
| r.ru_majflt = p->maj_flt + p->cmaj_flt; |
| r.ru_nswap = p->nswap + p->cnswap; |
| break; |
| } |
| return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
| } |
| |
| asmlinkage long sys_getrusage(int who, struct rusage *ru) |
| { |
| if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN) |
| return -EINVAL; |
| return getrusage(current, who, ru); |
| } |
| |
| asmlinkage long sys_umask(int mask) |
| { |
| mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); |
| return mask; |
| } |
| |
| asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, |
| unsigned long arg4, unsigned long arg5) |
| { |
| int error; |
| int sig; |
| |
| error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
| if (error) |
| return error; |
| |
| switch (option) { |
| case PR_SET_PDEATHSIG: |
| sig = arg2; |
| if (sig < 0 || sig > _NSIG) { |
| error = -EINVAL; |
| break; |
| } |
| current->pdeath_signal = sig; |
| break; |
| case PR_GET_PDEATHSIG: |
| error = put_user(current->pdeath_signal, (int *)arg2); |
| break; |
| case PR_GET_DUMPABLE: |
| if (current->mm->dumpable) |
| error = 1; |
| break; |
| case PR_SET_DUMPABLE: |
| if (arg2 != 0 && arg2 != 1) { |
| error = -EINVAL; |
| break; |
| } |
| current->mm->dumpable = arg2; |
| break; |
| |
| case PR_SET_UNALIGN: |
| error = SET_UNALIGN_CTL(current, arg2); |
| break; |
| case PR_GET_UNALIGN: |
| error = GET_UNALIGN_CTL(current, arg2); |
| break; |
| case PR_SET_FPEMU: |
| error = SET_FPEMU_CTL(current, arg2); |
| break; |
| case PR_GET_FPEMU: |
| error = GET_FPEMU_CTL(current, arg2); |
| break; |
| case PR_SET_FPEXC: |
| error = SET_FPEXC_CTL(current, arg2); |
| break; |
| case PR_GET_FPEXC: |
| error = GET_FPEXC_CTL(current, arg2); |
| break; |
| |
| |
| case PR_GET_KEEPCAPS: |
| if (current->keep_capabilities) |
| error = 1; |
| break; |
| case PR_SET_KEEPCAPS: |
| if (arg2 != 0 && arg2 != 1) { |
| error = -EINVAL; |
| break; |
| } |
| current->keep_capabilities = arg2; |
| break; |
| default: |
| error = -EINVAL; |
| break; |
| } |
| return error; |
| } |
| |
| EXPORT_SYMBOL(notifier_chain_register); |
| EXPORT_SYMBOL(notifier_chain_unregister); |
| EXPORT_SYMBOL(notifier_call_chain); |
| EXPORT_SYMBOL(register_reboot_notifier); |
| EXPORT_SYMBOL(unregister_reboot_notifier); |
| EXPORT_SYMBOL(in_group_p); |
| EXPORT_SYMBOL(in_egroup_p); |