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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 12:22:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 12:22:13 -0800
commit9977d9b379cb77e0f67bd6f4563618106e58e11d (patch)
tree0191accfddf578edb52c69c933d64521e3dce297 /kernel
parentcf4af01221579a4e895f43dbfc47598fbfc5a731 (diff)
parent541880d9a2c7871f6370071d55aa6662d329c51e (diff)
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.c102
-rw-r--r--kernel/exit.c92
-rw-r--r--kernel/fork.c64
-rw-r--r--kernel/signal.c15
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(&current->sibling, &current->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(&regs), 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);
}
/*