2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------ ptrace_signal_wake_up() From: Oleg Nesterov <[email protected]> ptrace: introduce signal_wake_up_state() and ptrace_signal_wake_up() CVE-2013-0871 BugLink: http://bugs.launchpad.net/bugs/1129192 Cleanup and preparation for the next change. signal_wake_up(resume => true) is overused. None of ptrace/jctl callers actually want to wakeup a TASK_WAKEKILL task, but they can't specify the necessary mask. Turn signal_wake_up() into signal_wake_up_state(state), reintroduce signal_wake_up() as a trivial helper, and add ptrace_signal_wake_up() which adds __TASK_TRACED. This way ptrace_signal_wake_up() can work "inside" ptrace_request() even if the tracee doesn't have the TASK_WAKEKILL bit set. Signed-off-by: Oleg Nesterov <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> (backported from commit 910ffdb18a6408e14febbb6e4b6840fd2c928c82) Conflicts: kernel/ptrace.c kernel/signal.c Signed-off-by: Luis Henriques <[email protected]> Acked-by: Colin King <[email protected]> Signed-off-by: Tim Gardner <[email protected]> Signed-off-by: Willy Tarreau <[email protected]> --- include/linux/sched.h | 11 ++++++++++- kernel/ptrace.c | 2 +- kernel/signal.c | 12 +++--------- 3 files changed, 14 insertions(+), 11 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 71849bf..73c3b9b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2459,7 +2459,16 @@ static inline void thread_group_cputime_free(struct signal_struct *sig) extern void recalc_sigpending_and_wake(struct task_struct *t); extern void recalc_sigpending(void); -extern void signal_wake_up(struct task_struct *t, int resume_stopped); +extern void signal_wake_up_state(struct task_struct *t, unsigned int state); + +static inline void signal_wake_up(struct task_struct *t, bool resume) +{ + signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); +} +static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) +{ + signal_wake_up_state(t, resume ? __TASK_TRACED : 0); +} /* * Wrappers for p->thread_info->cpu access. No-op on UP. diff --git a/kernel/ptrace.c b/kernel/ptrace.c index d8184b5..37850f9 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -56,7 +56,7 @@ static void ptrace_untrace(struct task_struct *child) child->signal->group_stop_count) __set_task_state(child, TASK_STOPPED); else - signal_wake_up(child, 1); + ptrace_signal_wake_up(child, true); } spin_unlock(&child->sighand->siglock); } diff --git a/kernel/signal.c b/kernel/signal.c index df993fd..b40f4f0 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -516,23 +516,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) * No need to set need_resched since signal event passing * goes through ->blocked */ -void signal_wake_up(struct task_struct *t, int resume) +void signal_wake_up_state(struct task_struct *t, unsigned int state) { - unsigned int mask; - set_tsk_thread_flag(t, TIF_SIGPENDING); - /* - * For SIGKILL, we want to wake it up in the stopped/traced/killable + * TASK_WAKEKILL also means wake it up in the stopped/traced/killable * case. We don't check t->state here because there is a race with it * executing another processor and just now entering stopped state. * By using wake_up_state, we ensure the process will wake up and * handle its death signal. */ - mask = TASK_INTERRUPTIBLE; - if (resume) - mask |= TASK_WAKEKILL; - if (!wake_up_state(t, mask)) + if (!wake_up_state(t, state | TASK_INTERRUPTIBLE)) kick_process(t); } -- 1.7.12.2.21.g234cd45.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
