diff options
45 files changed, 220 insertions, 186 deletions
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 @@ do_notify_resume(struct pt_regs *regs, struct switch_stack *sw, 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..63f327d 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -679,7 +679,5 @@ do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) 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 @@ fault_exit_work: 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, struct thread_info *ti) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags, 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 @@ void do_notify_resume(int canrestart, struct pt_regs *regs, 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 @@ asmlinkage void do_notify_resume(__u32 thread_info_flags) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags) 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 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) 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 @@ do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall) 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 @@ void do_notify_resume(struct pt_regs *regs, __u32 thread_info_flags) 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 @@ void do_notify_resume(struct pt_regs *regs) 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 @@ void do_notify_resume(struct pt_regs *regs, int in_syscall) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs) 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 @@ syscall_check_resched: .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 @@ void do_notify_resume(struct pt_regs *regs, long in_syscall) 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 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) 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 @@ void do_notify_resume(struct pt_regs *regs) { 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0, 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned long thread_info 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 @@ void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, 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 @@ void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long 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 @@ int do_work_pending(struct pt_regs *regs, u32 thread_info_flags) 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 @@ void interrupt_end(void) 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 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, 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 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) 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 @@ void do_notify_resume(struct pt_regs *regs) 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 @@ request_any_context_irq(unsigned int irq, irq_handler_t handler, 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 @@ request_percpu_irq(unsigned int irq, irq_handler_t handler, { 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 @@ static inline bool key_is_instantiated(const struct key *key) #ifdef CONFIG_SYSCTL extern ctl_table key_sysctls[]; #endif - -extern void key_replace_session_keyring(void); - /* * the userspace interface */ @@ -334,7 +331,6 @@ extern void key_init(void); #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 @@ struct task_struct { 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 @@ struct task_struct { /* 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 @@ struct task_struct { * 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 @@ struct task_struct { 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 @@ static inline void tracehook_signal_handler(int sig, siginfo_t *info, 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 tracehook_signal_handler(int sig, siginfo_t *info, */ 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 set_notify_resume(struct task_struct *task) */ 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 @@ void exit_creds(struct task_struct *tsk) 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 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) 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 6d85655..34867cc 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -946,12 +946,13 @@ void do_exit(long code) 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 @@ static struct task_struct *copy_process(unsigned long clone_flags, */ 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 @@ static void wake_threads_waitq(struct irq_desc *desc) 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 @@ static int irq_thread(void *data) 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 @@ static int irq_thread(void *data) * 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..3dcbf86 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 @@ extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, #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_get_security(key_serial_t keyid, */ 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 @@ long keyctl_session_to_parent(void) 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 @@ error: * 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; - - if (!current->replacement_session_keyring) - return; + const struct cred *old = current_cred(); + struct cred *new = twork->data; - write_lock_irq(&tasklist_lock); - new = current->replacement_session_keyring; - current->replacement_session_keyring = NULL; - write_unlock_irq(&tasklist_lock); - - if (!new) + kfree(twork); + if (unlikely(current->flags & PF_EXITING)) { + put_cred(new); return; + } - old = current_cred(); new-> uid = old-> uid; new-> euid = old-> euid; new-> suid = old-> suid; |
