Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull second pile of signal handling patches from Al Viro:
"This one is just task_work_add() series + remaining prereqs for it.
There probably will be another pull request from that tree this
cycle - at least for helpers, to get them out of the way for per-arch
fixes remaining in the tree."
Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile
had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the
pr_foo() infrastructure to prefix printks") which changed one of the
pr_err() calls that this merge moves around.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
keys: kill task_struct->replacement_session_keyring
keys: kill the dummy key_replace_session_keyring()
keys: change keyctl_session_to_parent() to use task_work_add()
genirq: reimplement exit_irq_thread() hook via task_work_add()
task_work_add: generic process-context callbacks
avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers
parisc: need to check NOTIFY_RESUME when exiting from syscall
move key_repace_session_keyring() into tracehook_notify_resume()
TIF_NOTIFY_RESUME is defined on all targets now
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index 10ab2d7..f6db303 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -590,7 +590,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 17fc36c..63f327dd 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -679,7 +679,5 @@
if (thread_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/avr32/kernel/entry-avr32b.S b/arch/avr32/kernel/entry-avr32b.S
index 169268c..5e6beb2 100644
--- a/arch/avr32/kernel/entry-avr32b.S
+++ b/arch/avr32/kernel/entry-avr32b.S
@@ -587,7 +587,7 @@
ld.w r1, r0[TI_flags]
rjmp fault_exit_work
-1: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK
+1: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NOTIFY_RESUME
tst r1, r2
breq 2f
unmask_interrupts
diff --git a/arch/avr32/kernel/signal.c b/arch/avr32/kernel/signal.c
index ae386c3..e7595ef 100644
--- a/arch/avr32/kernel/signal.c
+++ b/arch/avr32/kernel/signal.c
@@ -321,7 +321,5 @@
if (ti->flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/blackfin/kernel/signal.c b/arch/blackfin/kernel/signal.c
index e5bbc1a..fc9ecce 100644
--- a/arch/blackfin/kernel/signal.c
+++ b/arch/blackfin/kernel/signal.c
@@ -336,8 +336,6 @@
if (test_thread_flag(TIF_NOTIFY_RESUME)) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/c6x/kernel/signal.c b/arch/c6x/kernel/signal.c
index cf37478..9493f0b 100644
--- a/arch/c6x/kernel/signal.c
+++ b/arch/c6x/kernel/signal.c
@@ -364,7 +364,5 @@
if (thread_info_flags & (1 << TIF_NOTIFY_RESUME)) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/cris/kernel/ptrace.c b/arch/cris/kernel/ptrace.c
index d114ad3..58d44ee 100644
--- a/arch/cris/kernel/ptrace.c
+++ b/arch/cris/kernel/ptrace.c
@@ -40,7 +40,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/frv/kernel/signal.c b/arch/frv/kernel/signal.c
index 8cf5dca..595bf1e 100644
--- a/arch/frv/kernel/signal.c
+++ b/arch/frv/kernel/signal.c
@@ -562,8 +562,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(__frame);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
} /* end do_notify_resume() */
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
index d4b0555..e58992a 100644
--- a/arch/h8300/kernel/signal.c
+++ b/arch/h8300/kernel/signal.c
@@ -513,7 +513,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/hexagon/kernel/signal.c b/arch/hexagon/kernel/signal.c
index 434866e..21a3018 100644
--- a/arch/hexagon/kernel/signal.c
+++ b/arch/hexagon/kernel/signal.c
@@ -273,8 +273,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 5e0e86d..dd6fc14 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -199,8 +199,6 @@
if (test_thread_flag(TIF_NOTIFY_RESUME)) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(&scr->pt);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
/* copy user rbs to kernel rbs */
diff --git a/arch/m32r/kernel/signal.c b/arch/m32r/kernel/signal.c
index f54d969..64804f1 100644
--- a/arch/m32r/kernel/signal.c
+++ b/arch/m32r/kernel/signal.c
@@ -383,8 +383,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
clear_thread_flag(TIF_IRET);
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index d9f3d19..973eec6 100644
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c
@@ -1193,9 +1193,6 @@
if (test_thread_flag(TIF_SIGPENDING))
do_signal(regs);
- if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
+ if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
- }
}
diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index 7f4c7be..5d796e3 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c
@@ -401,9 +401,6 @@
if (test_thread_flag(TIF_SIGPENDING))
do_signal(regs, in_syscall);
- if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
+ if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
- }
}
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 17f6ee3..8a6e6d1 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -636,8 +636,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/mn10300/kernel/signal.c b/arch/mn10300/kernel/signal.c
index 890cf91..b8b6aa1 100644
--- a/arch/mn10300/kernel/signal.c
+++ b/arch/mn10300/kernel/signal.c
@@ -554,7 +554,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(current_frame());
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
index e970743..9ae6115 100644
--- a/arch/openrisc/kernel/signal.c
+++ b/arch/openrisc/kernel/signal.c
@@ -376,7 +376,5 @@
if (current_thread_info()->flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index 07ef351..c7fbc96 100644
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -2032,7 +2032,7 @@
.import do_signal,code
syscall_check_sig:
LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
- ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK), %r26
+ ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r26
and,COND(<>) %r19, %r26, %r0
b,n syscall_restore /* skip past if we've nothing to do */
diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
index 4b9cb0d..e7a7cd3 100644
--- a/arch/parisc/kernel/signal.c
+++ b/arch/parisc/kernel/signal.c
@@ -638,7 +638,5 @@
if (test_thread_flag(TIF_NOTIFY_RESUME)) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 651c596..bfc3ec13 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -193,8 +193,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index f626232..42a6e8b 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -494,6 +494,4 @@
{
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
diff --git a/arch/score/kernel/signal.c b/arch/score/kernel/signal.c
index d4a49011..302838d 100644
--- a/arch/score/kernel/signal.c
+++ b/arch/score/kernel/signal.c
@@ -356,7 +356,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
index cb4172c..9d7bfd6 100644
--- a/arch/sh/kernel/signal_32.c
+++ b/arch/sh/kernel/signal_32.c
@@ -626,7 +626,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/sh/kernel/signal_64.c b/arch/sh/kernel/signal_64.c
index b589a35..aa64284 100644
--- a/arch/sh/kernel/signal_64.c
+++ b/arch/sh/kernel/signal_64.c
@@ -685,7 +685,5 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 2b7e849..6b42e86 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -590,8 +590,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index eafaab4..c82cf1c 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -607,8 +607,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c
index ba1023d..6be7991 100644
--- a/arch/tile/kernel/process.c
+++ b/arch/tile/kernel/process.c
@@ -565,8 +565,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
return 1;
}
if (thread_info_flags & _TIF_SINGLESTEP) {
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 3a2235e..ccb9a9d 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -117,11 +117,8 @@
schedule();
if (test_thread_flag(TIF_SIGPENDING))
do_signal();
- if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
+ if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
tracehook_notify_resume(¤t->thread.regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
- }
}
void exit_thread(void)
diff --git a/arch/unicore32/kernel/signal.c b/arch/unicore32/kernel/signal.c
index 7754df6..28782ad 100644
--- a/arch/unicore32/kernel/signal.c
+++ b/arch/unicore32/kernel/signal.c
@@ -464,8 +464,6 @@
if (thread_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
}
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 965dfda..2e937a5 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -827,8 +827,6 @@
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
if (thread_info_flags & _TIF_USER_RETURN_NOTIFY)
fire_user_return_notifiers();
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index c5e4ec0..ea7e177 100644
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -548,9 +548,6 @@
if (test_thread_flag(TIF_SIGPENDING))
do_signal(regs);
- if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
+ if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
- }
}
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index c911715..e68a8e5 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -142,8 +142,6 @@
extern int __must_check
request_percpu_irq(unsigned int irq, irq_handler_t handler,
const char *devname, void __percpu *percpu_dev_id);
-
-extern void exit_irq_thread(void);
#else
extern int __must_check
@@ -177,8 +175,6 @@
{
return request_irq(irq, handler, 0, devname, percpu_dev_id);
}
-
-static inline void exit_irq_thread(void) { }
#endif
extern void free_irq(unsigned int, void *);
diff --git a/include/linux/key.h b/include/linux/key.h
index 52318007..4cd22ed 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -308,9 +308,6 @@
#ifdef CONFIG_SYSCTL
extern ctl_table key_sysctls[];
#endif
-
-extern void key_replace_session_keyring(void);
-
/*
* the userspace interface
*/
@@ -334,7 +331,6 @@
#define key_fsuid_changed(t) do { } while(0)
#define key_fsgid_changed(t) do { } while(0)
#define key_init() do { } while(0)
-#define key_replace_session_keyring() do { } while(0)
#endif /* CONFIG_KEYS */
#endif /* __KERNEL__ */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index f45c0b2..660c8ae 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1301,11 +1301,6 @@
unsigned sched_reset_on_fork:1;
unsigned sched_contributes_to_load:1;
-#ifdef CONFIG_GENERIC_HARDIRQS
- /* IRQ handler threads */
- unsigned irq_thread:1;
-#endif
-
pid_t pid;
pid_t tgid;
@@ -1313,10 +1308,9 @@
/* Canary value for the -fstack-protector gcc feature */
unsigned long stack_canary;
#endif
-
- /*
+ /*
* pointers to (original) parent process, youngest child, younger sibling,
- * older sibling, respectively. (p->father can be replaced with
+ * older sibling, respectively. (p->father can be replaced with
* p->real_parent->pid)
*/
struct task_struct __rcu *real_parent; /* real parent process */
@@ -1363,8 +1357,6 @@
* credentials (COW) */
const struct cred __rcu *cred; /* effective (overridable) subjective task
* credentials (COW) */
- struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
-
char comm[TASK_COMM_LEN]; /* executable name excluding path
- access with [gs]et_task_comm (which lock
it with task_lock())
@@ -1400,6 +1392,8 @@
int (*notifier)(void *priv);
void *notifier_data;
sigset_t *notifier_mask;
+ struct hlist_head task_works;
+
struct audit_context *audit_context;
#ifdef CONFIG_AUDITSYSCALL
uid_t loginuid;
diff --git a/include/linux/task_work.h b/include/linux/task_work.h
new file mode 100644
index 0000000..294d5d5
--- /dev/null
+++ b/include/linux/task_work.h
@@ -0,0 +1,33 @@
+#ifndef _LINUX_TASK_WORK_H
+#define _LINUX_TASK_WORK_H
+
+#include <linux/list.h>
+#include <linux/sched.h>
+
+struct task_work;
+typedef void (*task_work_func_t)(struct task_work *);
+
+struct task_work {
+ struct hlist_node hlist;
+ task_work_func_t func;
+ void *data;
+};
+
+static inline void
+init_task_work(struct task_work *twork, task_work_func_t func, void *data)
+{
+ twork->func = func;
+ twork->data = data;
+}
+
+int task_work_add(struct task_struct *task, struct task_work *twork, bool);
+struct task_work *task_work_cancel(struct task_struct *, task_work_func_t);
+void task_work_run(void);
+
+static inline void exit_task_work(struct task_struct *task)
+{
+ if (unlikely(!hlist_empty(&task->task_works)))
+ task_work_run();
+}
+
+#endif /* _LINUX_TASK_WORK_H */
diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h
index 51bd91d..6a4d82b 100644
--- a/include/linux/tracehook.h
+++ b/include/linux/tracehook.h
@@ -49,6 +49,7 @@
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/security.h>
+#include <linux/task_work.h>
struct linux_binprm;
/*
@@ -153,7 +154,6 @@
ptrace_notify(SIGTRAP);
}
-#ifdef TIF_NOTIFY_RESUME
/**
* set_notify_resume - cause tracehook_notify_resume() to be called
* @task: task that will call tracehook_notify_resume()
@@ -165,8 +165,10 @@
*/
static inline void set_notify_resume(struct task_struct *task)
{
+#ifdef TIF_NOTIFY_RESUME
if (!test_and_set_tsk_thread_flag(task, TIF_NOTIFY_RESUME))
kick_process(task);
+#endif
}
/**
@@ -184,7 +186,14 @@
*/
static inline void tracehook_notify_resume(struct pt_regs *regs)
{
+ /*
+ * The caller just cleared TIF_NOTIFY_RESUME. This barrier
+ * pairs with task_work_add()->set_notify_resume() after
+ * hlist_add_head(task->task_works);
+ */
+ smp_mb__after_clear_bit();
+ if (unlikely(!hlist_empty(¤t->task_works)))
+ task_work_run();
}
-#endif /* TIF_NOTIFY_RESUME */
#endif /* <linux/tracehook.h> */
diff --git a/kernel/Makefile b/kernel/Makefile
index 80be6ca..6f3d0ae 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -5,7 +5,7 @@
obj-y = fork.o exec_domain.o panic.o printk.o \
cpu.o exit.o itimer.o time.o softirq.o resource.o \
sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \
- signal.o sys.o kmod.o workqueue.o pid.o \
+ signal.o sys.o kmod.o workqueue.o pid.o task_work.o \
rcupdate.o extable.o params.o posix-timers.o \
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
diff --git a/kernel/cred.c b/kernel/cred.c
index 430557e..de728ac 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -207,13 +207,6 @@
validate_creds(cred);
alter_cred_subscribers(cred, -1);
put_cred(cred);
-
- cred = (struct cred *) tsk->replacement_session_keyring;
- if (cred) {
- tsk->replacement_session_keyring = NULL;
- validate_creds(cred);
- put_cred(cred);
- }
}
/**
@@ -396,8 +389,6 @@
struct cred *new;
int ret;
- p->replacement_session_keyring = NULL;
-
if (
#ifdef CONFIG_KEYS
!p->cred->thread_keyring &&
diff --git a/kernel/exit.c b/kernel/exit.c
index 6d856553..34867cc 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -946,12 +946,13 @@
exit_signals(tsk); /* sets PF_EXITING */
/*
* tsk->flags are checked in the futex code to protect against
- * an exiting task cleaning up the robust pi futexes.
+ * an exiting task cleaning up the robust pi futexes, and in
+ * task_work_add() to avoid the race with exit_task_work().
*/
smp_mb();
raw_spin_unlock_wait(&tsk->pi_lock);
- exit_irq_thread();
+ exit_task_work(tsk);
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
diff --git a/kernel/fork.c b/kernel/fork.c
index c55b61a..ab5211b 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1415,6 +1415,7 @@
*/
p->group_leader = p;
INIT_LIST_HEAD(&p->thread_group);
+ INIT_HLIST_HEAD(&p->task_works);
/* Now that the task is set up, run cgroup callbacks if
* necessary. We need to run them before the task is visible
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 7c475cd..ea0c6c2 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -16,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/task_work.h>
#include "internals.h"
@@ -775,11 +776,39 @@
wake_up(&desc->wait_for_threads);
}
+static void irq_thread_dtor(struct task_work *unused)
+{
+ struct task_struct *tsk = current;
+ struct irq_desc *desc;
+ struct irqaction *action;
+
+ if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
+ return;
+
+ action = kthread_data(tsk);
+
+ pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
+
+
+ desc = irq_to_desc(action->irq);
+ /*
+ * If IRQTF_RUNTHREAD is set, we need to decrement
+ * desc->threads_active and wake possible waiters.
+ */
+ if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ wake_threads_waitq(desc);
+
+ /* Prevent a stale desc->threads_oneshot */
+ irq_finalize_oneshot(desc, action);
+}
+
/*
* Interrupt handler thread
*/
static int irq_thread(void *data)
{
+ struct task_work on_exit_work;
static const struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
@@ -795,7 +824,9 @@
handler_fn = irq_thread_fn;
sched_setscheduler(current, SCHED_FIFO, ¶m);
- current->irq_thread = 1;
+
+ init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+ task_work_add(current, &on_exit_work, false);
while (!irq_wait_for_interrupt(action)) {
irqreturn_t action_ret;
@@ -817,44 +848,11 @@
* cannot touch the oneshot mask at this point anymore as
* __setup_irq() might have given out currents thread_mask
* again.
- *
- * Clear irq_thread. Otherwise exit_irq_thread() would make
- * fuzz about an active irq thread going into nirvana.
*/
- current->irq_thread = 0;
+ task_work_cancel(current, irq_thread_dtor);
return 0;
}
-/*
- * Called from do_exit()
- */
-void exit_irq_thread(void)
-{
- struct task_struct *tsk = current;
- struct irq_desc *desc;
- struct irqaction *action;
-
- if (!tsk->irq_thread)
- return;
-
- action = kthread_data(tsk);
-
- pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
- tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
-
- desc = irq_to_desc(action->irq);
-
- /*
- * If IRQTF_RUNTHREAD is set, we need to decrement
- * desc->threads_active and wake possible waiters.
- */
- if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
- wake_threads_waitq(desc);
-
- /* Prevent a stale desc->threads_oneshot */
- irq_finalize_oneshot(desc, action);
-}
-
static void irq_setup_forced_threading(struct irqaction *new)
{
if (!force_irqthreads)
diff --git a/kernel/task_work.c b/kernel/task_work.c
new file mode 100644
index 0000000..82d1c79
--- /dev/null
+++ b/kernel/task_work.c
@@ -0,0 +1,84 @@
+#include <linux/spinlock.h>
+#include <linux/task_work.h>
+#include <linux/tracehook.h>
+
+int
+task_work_add(struct task_struct *task, struct task_work *twork, bool notify)
+{
+ unsigned long flags;
+ int err = -ESRCH;
+
+#ifndef TIF_NOTIFY_RESUME
+ if (notify)
+ return -ENOTSUPP;
+#endif
+ /*
+ * We must not insert the new work if the task has already passed
+ * exit_task_work(). We rely on do_exit()->raw_spin_unlock_wait()
+ * and check PF_EXITING under pi_lock.
+ */
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ if (likely(!(task->flags & PF_EXITING))) {
+ hlist_add_head(&twork->hlist, &task->task_works);
+ err = 0;
+ }
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ /* test_and_set_bit() implies mb(), see tracehook_notify_resume(). */
+ if (likely(!err) && notify)
+ set_notify_resume(task);
+ return err;
+}
+
+struct task_work *
+task_work_cancel(struct task_struct *task, task_work_func_t func)
+{
+ unsigned long flags;
+ struct task_work *twork;
+ struct hlist_node *pos;
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ hlist_for_each_entry(twork, pos, &task->task_works, hlist) {
+ if (twork->func == func) {
+ hlist_del(&twork->hlist);
+ goto found;
+ }
+ }
+ twork = NULL;
+ found:
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ return twork;
+}
+
+void task_work_run(void)
+{
+ struct task_struct *task = current;
+ struct hlist_head task_works;
+ struct hlist_node *pos;
+
+ raw_spin_lock_irq(&task->pi_lock);
+ hlist_move_list(&task->task_works, &task_works);
+ raw_spin_unlock_irq(&task->pi_lock);
+
+ if (unlikely(hlist_empty(&task_works)))
+ return;
+ /*
+ * We use hlist to save the space in task_struct, but we want fifo.
+ * Find the last entry, the list should be short, then process them
+ * in reverse order.
+ */
+ for (pos = task_works.first; pos->next; pos = pos->next)
+ ;
+
+ for (;;) {
+ struct hlist_node **pprev = pos->pprev;
+ struct task_work *twork = container_of(pos, struct task_work,
+ hlist);
+ twork->func(twork);
+
+ if (pprev == &task_works.first)
+ break;
+ pos = container_of(pprev, struct hlist_node, next);
+ }
+}
diff --git a/security/keys/internal.h b/security/keys/internal.h
index f711b09..3dcbf86b 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -14,6 +14,7 @@
#include <linux/sched.h>
#include <linux/key-type.h>
+#include <linux/task_work.h>
#ifdef __KDEBUG
#define kenter(FMT, ...) \
@@ -148,6 +149,7 @@
#define KEY_LOOKUP_FOR_UNLINK 0x04
extern long join_session_keyring(const char *name);
+extern void key_change_session_keyring(struct task_work *twork);
extern struct work_struct key_gc_work;
extern unsigned key_gc_delay;
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 21907ea..0f5b3f0 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1454,50 +1454,57 @@
*/
long keyctl_session_to_parent(void)
{
-#ifdef TIF_NOTIFY_RESUME
struct task_struct *me, *parent;
const struct cred *mycred, *pcred;
- struct cred *cred, *oldcred;
+ struct task_work *newwork, *oldwork;
key_ref_t keyring_r;
+ struct cred *cred;
int ret;
keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_LINK);
if (IS_ERR(keyring_r))
return PTR_ERR(keyring_r);
+ ret = -ENOMEM;
+ newwork = kmalloc(sizeof(struct task_work), GFP_KERNEL);
+ if (!newwork)
+ goto error_keyring;
+
/* our parent is going to need a new cred struct, a new tgcred struct
* and new security data, so we allocate them here to prevent ENOMEM in
* our parent */
- ret = -ENOMEM;
cred = cred_alloc_blank();
if (!cred)
- goto error_keyring;
+ goto error_newwork;
cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r);
- keyring_r = NULL;
+ init_task_work(newwork, key_change_session_keyring, cred);
me = current;
rcu_read_lock();
write_lock_irq(&tasklist_lock);
- parent = me->real_parent;
ret = -EPERM;
+ oldwork = NULL;
+ parent = me->real_parent;
/* the parent mustn't be init and mustn't be a kernel thread */
if (parent->pid <= 1 || !parent->mm)
- goto not_permitted;
+ goto unlock;
/* the parent must be single threaded */
if (!thread_group_empty(parent))
- goto not_permitted;
+ goto unlock;
/* the parent and the child must have different session keyrings or
* there's no point */
mycred = current_cred();
pcred = __task_cred(parent);
if (mycred == pcred ||
- mycred->tgcred->session_keyring == pcred->tgcred->session_keyring)
- goto already_same;
+ mycred->tgcred->session_keyring == pcred->tgcred->session_keyring) {
+ ret = 0;
+ goto unlock;
+ }
/* the parent must have the same effective ownership and mustn't be
* SUID/SGID */
@@ -1507,50 +1514,40 @@
pcred->gid != mycred->egid ||
pcred->egid != mycred->egid ||
pcred->sgid != mycred->egid)
- goto not_permitted;
+ goto unlock;
/* the keyrings must have the same UID */
if ((pcred->tgcred->session_keyring &&
pcred->tgcred->session_keyring->uid != mycred->euid) ||
mycred->tgcred->session_keyring->uid != mycred->euid)
- goto not_permitted;
+ goto unlock;
- /* if there's an already pending keyring replacement, then we replace
- * that */
- oldcred = parent->replacement_session_keyring;
+ /* cancel an already pending keyring replacement */
+ oldwork = task_work_cancel(parent, key_change_session_keyring);
/* the replacement session keyring is applied just prior to userspace
* restarting */
- parent->replacement_session_keyring = cred;
- cred = NULL;
- set_ti_thread_flag(task_thread_info(parent), TIF_NOTIFY_RESUME);
-
+ ret = task_work_add(parent, newwork, true);
+ if (!ret)
+ newwork = NULL;
+unlock:
write_unlock_irq(&tasklist_lock);
rcu_read_unlock();
- if (oldcred)
- put_cred(oldcred);
- return 0;
-
-already_same:
- ret = 0;
-not_permitted:
- write_unlock_irq(&tasklist_lock);
- rcu_read_unlock();
- put_cred(cred);
+ if (oldwork) {
+ put_cred(oldwork->data);
+ kfree(oldwork);
+ }
+ if (newwork) {
+ put_cred(newwork->data);
+ kfree(newwork);
+ }
return ret;
+error_newwork:
+ kfree(newwork);
error_keyring:
key_ref_put(keyring_r);
return ret;
-
-#else /* !TIF_NOTIFY_RESUME */
- /*
- * To be removed when TIF_NOTIFY_RESUME has been implemented on
- * m68k/xtensa
- */
-#warning TIF_NOTIFY_RESUME not implemented
- return -EOPNOTSUPP;
-#endif /* !TIF_NOTIFY_RESUME */
}
/*
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index d71056d..4ad54ee 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -834,23 +834,17 @@
* Replace a process's session keyring on behalf of one of its children when
* the target process is about to resume userspace execution.
*/
-void key_replace_session_keyring(void)
+void key_change_session_keyring(struct task_work *twork)
{
- const struct cred *old;
- struct cred *new;
+ const struct cred *old = current_cred();
+ struct cred *new = twork->data;
- if (!current->replacement_session_keyring)
+ kfree(twork);
+ if (unlikely(current->flags & PF_EXITING)) {
+ put_cred(new);
return;
+ }
- write_lock_irq(&tasklist_lock);
- new = current->replacement_session_keyring;
- current->replacement_session_keyring = NULL;
- write_unlock_irq(&tasklist_lock);
-
- if (!new)
- return;
-
- old = current_cred();
new-> uid = old-> uid;
new-> euid = old-> euid;
new-> suid = old-> suid;
