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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 12:22:13 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 12:22:13 -0800 |
commit | 9977d9b379cb77e0f67bd6f4563618106e58e11d (patch) | |
tree | 0191accfddf578edb52c69c933d64521e3dce297 /kernel | |
parent | cf4af01221579a4e895f43dbfc47598fbfc5a731 (diff) | |
parent | 541880d9a2c7871f6370071d55aa6662d329c51e (diff) | |
download | linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.tar.gz linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.tar.bz2 linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.zip |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull big execve/kernel_thread/fork unification series from Al Viro:
"All architectures are converted to new model. Quite a bit of that
stuff is actually shared with architecture trees; in such cases it's
literally shared branch pulled by both, not a cherry-pick.
A lot of ugliness and black magic is gone (-3KLoC total in this one):
- kernel_thread()/kernel_execve()/sys_execve() redesign.
We don't do syscalls from kernel anymore for either kernel_thread()
or kernel_execve():
kernel_thread() is essentially clone(2) with callback run before we
return to userland, the callbacks either never return or do
successful do_execve() before returning.
kernel_execve() is a wrapper for do_execve() - it doesn't need to
do transition to user mode anymore.
As a result kernel_thread() and kernel_execve() are
arch-independent now - they live in kernel/fork.c and fs/exec.c
resp. sys_execve() is also in fs/exec.c and it's completely
architecture-independent.
- daemonize() is gone, along with its parts in fs/*.c
- struct pt_regs * is no longer passed to do_fork/copy_process/
copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.
- sys_fork()/sys_vfork()/sys_clone() unified; some architectures
still need wrappers (ones with callee-saved registers not saved in
pt_regs on syscall entry), but the main part of those suckers is in
kernel/fork.c now."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
do_coredump(): get rid of pt_regs argument
print_fatal_signal(): get rid of pt_regs argument
ptrace_signal(): get rid of unused arguments
get rid of ptrace_signal_deliver() arguments
new helper: signal_pt_regs()
unify default ptrace_signal_deliver
flagday: kill pt_regs argument of do_fork()
death to idle_regs()
don't pass regs to copy_process()
flagday: don't pass regs to copy_thread()
bfin: switch to generic vfork, get rid of pointless wrappers
xtensa: switch to generic clone()
openrisc: switch to use of generic fork and clone
unicore32: switch to generic clone(2)
score: switch to generic fork/vfork/clone
c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
mn10300: switch to generic fork/vfork/clone
h8300: switch to generic fork/vfork/clone
tile: switch to generic clone()
...
Conflicts:
arch/microblaze/include/asm/Kbuild
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/auditsc.c | 102 | ||||
-rw-r--r-- | kernel/exit.c | 92 | ||||
-rw-r--r-- | kernel/fork.c | 64 | ||||
-rw-r--r-- | kernel/signal.c | 15 |
4 files changed, 76 insertions, 197 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index fc7376bf86ea..e37e6a12c5e3 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -200,7 +200,6 @@ struct audit_context { struct list_head names_list; /* anchor for struct audit_names->list */ char * filterkey; /* key for rule that triggered record */ struct path pwd; - struct audit_context *previous; /* For nested syscalls */ struct audit_aux_data *aux; struct audit_aux_data *aux_pids; struct sockaddr_storage *sockaddr; @@ -1091,29 +1090,13 @@ int audit_alloc(struct task_struct *tsk) static inline void audit_free_context(struct audit_context *context) { - struct audit_context *previous; - int count = 0; - - do { - previous = context->previous; - if (previous || (count && count < 10)) { - ++count; - printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" - " freeing multiple contexts (%d)\n", - context->serial, context->major, - context->name_count, count); - } - audit_free_names(context); - unroll_tree_refs(context, NULL, 0); - free_tree_refs(context); - audit_free_aux(context); - kfree(context->filterkey); - kfree(context->sockaddr); - kfree(context); - context = previous; - } while (context); - if (count >= 10) - printk(KERN_ERR "audit: freed %d contexts\n", count); + audit_free_names(context); + unroll_tree_refs(context, NULL, 0); + free_tree_refs(context); + audit_free_aux(context); + kfree(context->filterkey); + kfree(context->sockaddr); + kfree(context); } void audit_log_task_context(struct audit_buffer *ab) @@ -1783,42 +1766,6 @@ void __audit_syscall_entry(int arch, int major, if (!context) return; - /* - * This happens only on certain architectures that make system - * calls in kernel_thread via the entry.S interface, instead of - * with direct calls. (If you are porting to a new - * architecture, hitting this condition can indicate that you - * got the _exit/_leave calls backward in entry.S.) - * - * i386 no - * x86_64 no - * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) - * - * This also happens with vm86 emulation in a non-nested manner - * (entries without exits), so this case must be caught. - */ - if (context->in_syscall) { - struct audit_context *newctx; - -#if AUDIT_DEBUG - printk(KERN_ERR - "audit(:%d) pid=%d in syscall=%d;" - " entering syscall=%d\n", - context->serial, tsk->pid, context->major, major); -#endif - newctx = audit_alloc_context(context->state); - if (newctx) { - newctx->previous = context; - context = newctx; - tsk->audit_context = newctx; - } else { - /* If we can't alloc a new context, the best we - * can do is to leak memory (any pending putname - * will be lost). The only other alternative is - * to abandon auditing. */ - audit_zero_context(context, context->state); - } - } BUG_ON(context->in_syscall || context->name_count); if (!audit_enabled) @@ -1881,28 +1828,21 @@ void __audit_syscall_exit(int success, long return_code) if (!list_empty(&context->killed_trees)) audit_kill_trees(&context->killed_trees); - if (context->previous) { - struct audit_context *new_context = context->previous; - context->previous = NULL; - audit_free_context(context); - tsk->audit_context = new_context; - } else { - audit_free_names(context); - unroll_tree_refs(context, NULL, 0); - audit_free_aux(context); - context->aux = NULL; - context->aux_pids = NULL; - context->target_pid = 0; - context->target_sid = 0; - context->sockaddr_len = 0; - context->type = 0; - context->fds[0] = -1; - if (context->state != AUDIT_RECORD_CONTEXT) { - kfree(context->filterkey); - context->filterkey = NULL; - } - tsk->audit_context = context; + audit_free_names(context); + unroll_tree_refs(context, NULL, 0); + audit_free_aux(context); + context->aux = NULL; + context->aux_pids = NULL; + context->target_pid = 0; + context->target_sid = 0; + context->sockaddr_len = 0; + context->type = 0; + context->fds[0] = -1; + if (context->state != AUDIT_RECORD_CONTEXT) { + kfree(context->filterkey); + context->filterkey = NULL; } + tsk->audit_context = context; } static inline void handle_one(const struct inode *inode) diff --git a/kernel/exit.c b/kernel/exit.c index 618f7ee56003..50d2e93c36ea 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -322,43 +322,6 @@ kill_orphaned_pgrp(struct task_struct *tsk, struct task_struct *parent) } } -/** - * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd - * - * If a kernel thread is launched as a result of a system call, or if - * it ever exits, it should generally reparent itself to kthreadd so it - * isn't in the way of other processes and is correctly cleaned up on exit. - * - * The various task state such as scheduling policy and priority may have - * been inherited from a user process, so we reset them to sane values here. - * - * NOTE that reparent_to_kthreadd() gives the caller full capabilities. - */ -static void reparent_to_kthreadd(void) -{ - write_lock_irq(&tasklist_lock); - - ptrace_unlink(current); - /* Reparent to init */ - current->real_parent = current->parent = kthreadd_task; - list_move_tail(¤t->sibling, ¤t->real_parent->children); - - /* Set the exit signal to SIGCHLD so we signal init on exit */ - current->exit_signal = SIGCHLD; - - if (task_nice(current) < 0) - set_user_nice(current, 0); - /* cpus_allowed? */ - /* rt_priority? */ - /* signals? */ - memcpy(current->signal->rlim, init_task.signal->rlim, - sizeof(current->signal->rlim)); - - atomic_inc(&init_cred.usage); - commit_creds(&init_cred); - write_unlock_irq(&tasklist_lock); -} - void __set_special_pids(struct pid *pid) { struct task_struct *curr = current->group_leader; @@ -370,13 +333,6 @@ void __set_special_pids(struct pid *pid) change_pid(curr, PIDTYPE_PGID, pid); } -static void set_special_pids(struct pid *pid) -{ - write_lock_irq(&tasklist_lock); - __set_special_pids(pid); - write_unlock_irq(&tasklist_lock); -} - /* * Let kernel threads use this to say that they allow a certain signal. * Must not be used if kthread was cloned with CLONE_SIGHAND. @@ -416,54 +372,6 @@ int disallow_signal(int sig) EXPORT_SYMBOL(disallow_signal); -/* - * Put all the gunge required to become a kernel thread without - * attached user resources in one place where it belongs. - */ - -void daemonize(const char *name, ...) -{ - va_list args; - sigset_t blocked; - - va_start(args, name); - vsnprintf(current->comm, sizeof(current->comm), name, args); - va_end(args); - - /* - * If we were started as result of loading a module, close all of the - * user space pages. We don't need them, and if we didn't close them - * they would be locked into memory. - */ - exit_mm(current); - /* - * We don't want to get frozen, in case system-wide hibernation - * or suspend transition begins right now. - */ - current->flags |= (PF_NOFREEZE | PF_KTHREAD); - - if (current->nsproxy != &init_nsproxy) { - get_nsproxy(&init_nsproxy); - switch_task_namespaces(current, &init_nsproxy); - } - set_special_pids(&init_struct_pid); - proc_clear_tty(current); - - /* Block and flush all signals */ - sigfillset(&blocked); - sigprocmask(SIG_BLOCK, &blocked, NULL); - flush_signals(current); - - /* Become as one with the init task */ - - daemonize_fs_struct(); - daemonize_descriptors(); - - reparent_to_kthreadd(); -} - -EXPORT_SYMBOL(daemonize); - #ifdef CONFIG_MM_OWNER /* * A task is exiting. If it owned this mm, find a new owner for the mm. diff --git a/kernel/fork.c b/kernel/fork.c index 79de9f99a48d..3c31e874afad 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1129,7 +1129,6 @@ static void posix_cpu_timers_init(struct task_struct *tsk) */ static struct task_struct *copy_process(unsigned long clone_flags, unsigned long stack_start, - struct pt_regs *regs, unsigned long stack_size, int __user *child_tidptr, struct pid *pid, @@ -1321,7 +1320,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, retval = copy_io(clone_flags, p); if (retval) goto bad_fork_cleanup_namespaces; - retval = copy_thread(clone_flags, stack_start, stack_size, p, regs); + retval = copy_thread(clone_flags, stack_start, stack_size, p); if (retval) goto bad_fork_cleanup_io; @@ -1510,12 +1509,6 @@ fork_out: return ERR_PTR(retval); } -noinline struct pt_regs * __cpuinit __attribute__((weak)) idle_regs(struct pt_regs *regs) -{ - memset(regs, 0, sizeof(struct pt_regs)); - return regs; -} - static inline void init_idle_pids(struct pid_link *links) { enum pid_type type; @@ -1529,10 +1522,7 @@ static inline void init_idle_pids(struct pid_link *links) struct task_struct * __cpuinit fork_idle(int cpu) { struct task_struct *task; - struct pt_regs regs; - - task = copy_process(CLONE_VM, 0, idle_regs(®s), 0, NULL, - &init_struct_pid, 0); + task = copy_process(CLONE_VM, 0, 0, NULL, &init_struct_pid, 0); if (!IS_ERR(task)) { init_idle_pids(task->pids); init_idle(task, cpu); @@ -1549,7 +1539,6 @@ struct task_struct * __cpuinit fork_idle(int cpu) */ long do_fork(unsigned long clone_flags, unsigned long stack_start, - struct pt_regs *regs, unsigned long stack_size, int __user *parent_tidptr, int __user *child_tidptr) @@ -1579,7 +1568,7 @@ long do_fork(unsigned long clone_flags, * requested, no event is reported; otherwise, report if the event * for the type of forking is enabled. */ - if (!(clone_flags & CLONE_UNTRACED) && likely(user_mode(regs))) { + if (!(clone_flags & CLONE_UNTRACED)) { if (clone_flags & CLONE_VFORK) trace = PTRACE_EVENT_VFORK; else if ((clone_flags & CSIGNAL) != SIGCHLD) @@ -1591,7 +1580,7 @@ long do_fork(unsigned long clone_flags, trace = 0; } - p = copy_process(clone_flags, stack_start, regs, stack_size, + p = copy_process(clone_flags, stack_start, stack_size, child_tidptr, NULL, trace); /* * Do this prior waking up the new thread - the thread pointer @@ -1635,11 +1624,54 @@ long do_fork(unsigned long clone_flags, */ pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) { - return do_fork(flags|CLONE_VM|CLONE_UNTRACED, (unsigned long)fn, NULL, + return do_fork(flags|CLONE_VM|CLONE_UNTRACED, (unsigned long)fn, (unsigned long)arg, NULL, NULL); } #endif +#ifdef __ARCH_WANT_SYS_FORK +SYSCALL_DEFINE0(fork) +{ +#ifdef CONFIG_MMU + return do_fork(SIGCHLD, 0, 0, NULL, NULL); +#else + /* can not support in nommu mode */ + return(-EINVAL); +#endif +} +#endif + +#ifdef __ARCH_WANT_SYS_VFORK +SYSCALL_DEFINE0(vfork) +{ + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, + 0, NULL, NULL); +} +#endif + +#ifdef __ARCH_WANT_SYS_CLONE +#ifdef CONFIG_CLONE_BACKWARDS +SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp, + int __user *, parent_tidptr, + int, tls_val, + int __user *, child_tidptr) +#elif defined(CONFIG_CLONE_BACKWARDS2) +SYSCALL_DEFINE5(clone, unsigned long, newsp, unsigned long, clone_flags, + int __user *, parent_tidptr, + int __user *, child_tidptr, + int, tls_val) +#else +SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp, + int __user *, parent_tidptr, + int __user *, child_tidptr, + int, tls_val) +#endif +{ + return do_fork(clone_flags, newsp, 0, + parent_tidptr, child_tidptr); +} +#endif + #ifndef ARCH_MIN_MMSTRUCT_ALIGN #define ARCH_MIN_MMSTRUCT_ALIGN 0 #endif diff --git a/kernel/signal.c b/kernel/signal.c index 5ffb5626e072..a49c7f36ceb3 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1159,8 +1159,9 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, return __send_signal(sig, info, t, group, from_ancestor_ns); } -static void print_fatal_signal(struct pt_regs *regs, int signr) +static void print_fatal_signal(int signr) { + struct pt_regs *regs = signal_pt_regs(); printk("%s/%d: potentially unexpected fatal signal %d.\n", current->comm, task_pid_nr(current), signr); @@ -2131,10 +2132,9 @@ static void do_jobctl_trap(void) } } -static int ptrace_signal(int signr, siginfo_t *info, - struct pt_regs *regs, void *cookie) +static int ptrace_signal(int signr, siginfo_t *info) { - ptrace_signal_deliver(regs, cookie); + ptrace_signal_deliver(); /* * We do not check sig_kernel_stop(signr) but set this marker * unconditionally because we do not know whether debugger will @@ -2257,8 +2257,7 @@ relock: break; /* will return 0 */ if (unlikely(current->ptrace) && signr != SIGKILL) { - signr = ptrace_signal(signr, info, - regs, cookie); + signr = ptrace_signal(signr, info); if (!signr) continue; } @@ -2343,7 +2342,7 @@ relock: if (sig_kernel_coredump(signr)) { if (print_fatal_signals) - print_fatal_signal(regs, info->si_signo); + print_fatal_signal(info->si_signo); /* * If it was able to dump core, this kills all * other threads in the group and synchronizes with @@ -2352,7 +2351,7 @@ relock: * first and our do_group_exit call below will use * that value and ignore the one we pass it. */ - do_coredump(info, regs); + do_coredump(info); } /* |