diff options
| -rw-r--r-- | drivers/usb/core/devio.c | 12 | ||||
| -rw-r--r-- | include/linux/sched.h | 1 | ||||
| -rw-r--r-- | kernel/signal.c | 34 |
3 files changed, 44 insertions, 3 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index b4265aa..6c35dcb 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -30,6 +30,8 @@ * Revision history * 22.12.1999 0.1 Initial release (split from proc_usb.c) * 04.01.2000 0.2 Turned into its own filesystem + * 30.09.2005 0.3 Fix user-triggerable oops in async URB delivery + * (CAN-2005-3055) */ /*****************************************************************************/ @@ -58,7 +60,8 @@ static struct class *usb_device_class; struct async { struct list_head asynclist; struct dev_state *ps; - struct task_struct *task; + pid_t pid; + uid_t uid, euid; unsigned int signr; unsigned int ifnum; void __user *userbuffer; @@ -290,7 +293,8 @@ static void async_completed(struct urb *urb, struct pt_regs *regs) sinfo.si_errno = as->urb->status; sinfo.si_code = SI_ASYNCIO; sinfo.si_addr = as->userurb; - send_sig_info(as->signr, &sinfo, as->task); + kill_proc_info_as_uid(as->signr, &sinfo, as->pid, as->uid, + as->euid); } wake_up(&ps->wait); } @@ -988,7 +992,9 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, as->userbuffer = NULL; as->signr = uurb->signr; as->ifnum = ifnum; - as->task = current; + as->pid = current->pid; + as->uid = current->uid; + as->euid = current->euid; if (!(uurb->endpoint & USB_DIR_IN)) { if (copy_from_user(as->urb->transfer_buffer, uurb->buffer, as->urb->transfer_buffer_length)) { free_async(as); diff --git a/include/linux/sched.h b/include/linux/sched.h index c3ba31f..27519df 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1018,6 +1018,7 @@ extern int force_sig_info(int, struct siginfo *, struct task_struct *); extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp); extern int kill_pg_info(int, struct siginfo *, pid_t); extern int kill_proc_info(int, struct siginfo *, pid_t); +extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t); extern void do_notify_parent(struct task_struct *, int); extern void force_sig(int, struct task_struct *); extern void force_sig_specific(int, struct task_struct *); diff --git a/kernel/signal.c b/kernel/signal.c index cba193c..50c9926 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1193,6 +1193,40 @@ kill_proc_info(int sig, struct siginfo *info, pid_t pid) return error; } +/* like kill_proc_info(), but doesn't use uid/euid of "current" */ +int kill_proc_info_as_uid(int sig, struct siginfo *info, pid_t pid, + uid_t uid, uid_t euid) +{ + int ret = -EINVAL; + struct task_struct *p; + + if (!valid_signal(sig)) + return ret; + + read_lock(&tasklist_lock); + p = find_task_by_pid(pid); + if (!p) { + ret = -ESRCH; + goto out_unlock; + } + if ((!info || ((unsigned long)info != 1 && + (unsigned long)info != 2 && SI_FROMUSER(info))) + && (euid != p->suid) && (euid != p->uid) + && (uid != p->suid) && (uid != p->uid)) { + ret = -EPERM; + goto out_unlock; + } + if (sig && p->sighand) { + unsigned long flags; + spin_lock_irqsave(&p->sighand->siglock, flags); + ret = __group_send_sig_info(sig, info, p); + spin_unlock_irqrestore(&p->sighand->siglock, flags); + } +out_unlock: + read_unlock(&tasklist_lock); + return ret; +} +EXPORT_SYMBOL_GPL(kill_proc_info_as_uid); /* * kill_something_info() interprets pid in interesting ways just like kill(2). |