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-rw-r--r--kernel/compat.c1
-rw-r--r--kernel/fork.c394
-rw-r--r--kernel/module.c3
-rw-r--r--kernel/power/console.c4
-rw-r--r--kernel/power/power.h16
-rw-r--r--kernel/power/swsusp.c6
-rw-r--r--kernel/signal.c9
-rw-r--r--kernel/sys.c2
-rw-r--r--kernel/timer.c2
9 files changed, 354 insertions, 83 deletions
diff --git a/kernel/compat.c b/kernel/compat.c
index 1867290c37e..8c9cd88b678 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -23,7 +23,6 @@
#include <linux/security.h>
#include <asm/uaccess.h>
-#include <asm/bug.h>
int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
{
diff --git a/kernel/fork.c b/kernel/fork.c
index 7f0ab5ee948..8e88b374cee 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -446,6 +446,55 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
}
}
+/*
+ * Allocate a new mm structure and copy contents from the
+ * mm structure of the passed in task structure.
+ */
+static struct mm_struct *dup_mm(struct task_struct *tsk)
+{
+ struct mm_struct *mm, *oldmm = current->mm;
+ int err;
+
+ if (!oldmm)
+ return NULL;
+
+ mm = allocate_mm();
+ if (!mm)
+ goto fail_nomem;
+
+ memcpy(mm, oldmm, sizeof(*mm));
+
+ if (!mm_init(mm))
+ goto fail_nomem;
+
+ if (init_new_context(tsk, mm))
+ goto fail_nocontext;
+
+ err = dup_mmap(mm, oldmm);
+ if (err)
+ goto free_pt;
+
+ mm->hiwater_rss = get_mm_rss(mm);
+ mm->hiwater_vm = mm->total_vm;
+
+ return mm;
+
+free_pt:
+ mmput(mm);
+
+fail_nomem:
+ return NULL;
+
+fail_nocontext:
+ /*
+ * If init_new_context() failed, we cannot use mmput() to free the mm
+ * because it calls destroy_context()
+ */
+ mm_free_pgd(mm);
+ free_mm(mm);
+ return NULL;
+}
+
static int copy_mm(unsigned long clone_flags, struct task_struct * tsk)
{
struct mm_struct * mm, *oldmm;
@@ -473,43 +522,17 @@ static int copy_mm(unsigned long clone_flags, struct task_struct * tsk)
}
retval = -ENOMEM;
- mm = allocate_mm();
+ mm = dup_mm(tsk);
if (!mm)
goto fail_nomem;
- /* Copy the current MM stuff.. */
- memcpy(mm, oldmm, sizeof(*mm));
- if (!mm_init(mm))
- goto fail_nomem;
-
- if (init_new_context(tsk,mm))
- goto fail_nocontext;
-
- retval = dup_mmap(mm, oldmm);
- if (retval)
- goto free_pt;
-
- mm->hiwater_rss = get_mm_rss(mm);
- mm->hiwater_vm = mm->total_vm;
-
good_mm:
tsk->mm = mm;
tsk->active_mm = mm;
return 0;
-free_pt:
- mmput(mm);
fail_nomem:
return retval;
-
-fail_nocontext:
- /*
- * If init_new_context() failed, we cannot use mmput() to free the mm
- * because it calls destroy_context()
- */
- mm_free_pgd(mm);
- free_mm(mm);
- return retval;
}
static inline struct fs_struct *__copy_fs_struct(struct fs_struct *old)
@@ -597,32 +620,17 @@ out:
return newf;
}
-static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
+/*
+ * Allocate a new files structure and copy contents from the
+ * passed in files structure.
+ */
+static struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
{
- struct files_struct *oldf, *newf;
+ struct files_struct *newf;
struct file **old_fds, **new_fds;
- int open_files, size, i, error = 0, expand;
+ int open_files, size, i, expand;
struct fdtable *old_fdt, *new_fdt;
- /*
- * A background process may not have any files ...
- */
- oldf = current->files;
- if (!oldf)
- goto out;
-
- if (clone_flags & CLONE_FILES) {
- atomic_inc(&oldf->count);
- goto out;
- }
-
- /*
- * Note: we may be using current for both targets (See exec.c)
- * This works because we cache current->files (old) as oldf. Don't
- * break this.
- */
- tsk->files = NULL;
- error = -ENOMEM;
newf = alloc_files();
if (!newf)
goto out;
@@ -651,9 +659,9 @@ static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
if (expand) {
spin_unlock(&oldf->file_lock);
spin_lock(&newf->file_lock);
- error = expand_files(newf, open_files-1);
+ *errorp = expand_files(newf, open_files-1);
spin_unlock(&newf->file_lock);
- if (error < 0)
+ if (*errorp < 0)
goto out_release;
new_fdt = files_fdtable(newf);
/*
@@ -702,10 +710,8 @@ static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
memset(&new_fdt->close_on_exec->fds_bits[start], 0, left);
}
- tsk->files = newf;
- error = 0;
out:
- return error;
+ return newf;
out_release:
free_fdset (new_fdt->close_on_exec, new_fdt->max_fdset);
@@ -715,6 +721,40 @@ out_release:
goto out;
}
+static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
+{
+ struct files_struct *oldf, *newf;
+ int error = 0;
+
+ /*
+ * A background process may not have any files ...
+ */
+ oldf = current->files;
+ if (!oldf)
+ goto out;
+
+ if (clone_flags & CLONE_FILES) {
+ atomic_inc(&oldf->count);
+ goto out;
+ }
+
+ /*
+ * Note: we may be using current for both targets (See exec.c)
+ * This works because we cache current->files (old) as oldf. Don't
+ * break this.
+ */
+ tsk->files = NULL;
+ error = -ENOMEM;
+ newf = dup_fd(oldf, &error);
+ if (!newf)
+ goto out;
+
+ tsk->files = newf;
+ error = 0;
+out:
+ return error;
+}
+
/*
* Helper to unshare the files of the current task.
* We don't want to expose copy_files internals to
@@ -1323,3 +1363,249 @@ void __init proc_caches_init(void)
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
}
+
+
+/*
+ * Check constraints on flags passed to the unshare system call and
+ * force unsharing of additional process context as appropriate.
+ */
+static inline void check_unshare_flags(unsigned long *flags_ptr)
+{
+ /*
+ * If unsharing a thread from a thread group, must also
+ * unshare vm.
+ */
+ if (*flags_ptr & CLONE_THREAD)
+ *flags_ptr |= CLONE_VM;
+
+ /*
+ * If unsharing vm, must also unshare signal handlers.
+ */
+ if (*flags_ptr & CLONE_VM)
+ *flags_ptr |= CLONE_SIGHAND;
+
+ /*
+ * If unsharing signal handlers and the task was created
+ * using CLONE_THREAD, then must unshare the thread
+ */
+ if ((*flags_ptr & CLONE_SIGHAND) &&
+ (atomic_read(&current->signal->count) > 1))
+ *flags_ptr |= CLONE_THREAD;
+
+ /*
+ * If unsharing namespace, must also unshare filesystem information.
+ */
+ if (*flags_ptr & CLONE_NEWNS)
+ *flags_ptr |= CLONE_FS;
+}
+
+/*
+ * Unsharing of tasks created with CLONE_THREAD is not supported yet
+ */
+static int unshare_thread(unsigned long unshare_flags)
+{
+ if (unshare_flags & CLONE_THREAD)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Unshare the filesystem structure if it is being shared
+ */
+static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
+{
+ struct fs_struct *fs = current->fs;
+
+ if ((unshare_flags & CLONE_FS) &&
+ (fs && atomic_read(&fs->count) > 1)) {
+ *new_fsp = __copy_fs_struct(current->fs);
+ if (!*new_fsp)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Unshare the namespace structure if it is being shared
+ */
+static int unshare_namespace(unsigned long unshare_flags, struct namespace **new_nsp, struct fs_struct *new_fs)
+{
+ struct namespace *ns = current->namespace;
+
+ if ((unshare_flags & CLONE_NEWNS) &&
+ (ns && atomic_read(&ns->count) > 1)) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ *new_nsp = dup_namespace(current, new_fs ? new_fs : current->fs);
+ if (!*new_nsp)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Unsharing of sighand for tasks created with CLONE_SIGHAND is not
+ * supported yet
+ */
+static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct **new_sighp)
+{
+ struct sighand_struct *sigh = current->sighand;
+
+ if ((unshare_flags & CLONE_SIGHAND) &&
+ (sigh && atomic_read(&sigh->count) > 1))
+ return -EINVAL;
+ else
+ return 0;
+}
+
+/*
+ * Unshare vm if it is being shared
+ */
+static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp)
+{
+ struct mm_struct *mm = current->mm;
+
+ if ((unshare_flags & CLONE_VM) &&
+ (mm && atomic_read(&mm->mm_users) > 1)) {
+ *new_mmp = dup_mm(current);
+ if (!*new_mmp)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Unshare file descriptor table if it is being shared
+ */
+static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp)
+{
+ struct files_struct *fd = current->files;
+ int error = 0;
+
+ if ((unshare_flags & CLONE_FILES) &&
+ (fd && atomic_read(&fd->count) > 1)) {
+ *new_fdp = dup_fd(fd, &error);
+ if (!*new_fdp)
+ return error;
+ }
+
+ return 0;
+}
+
+/*
+ * Unsharing of semundo for tasks created with CLONE_SYSVSEM is not
+ * supported yet
+ */
+static int unshare_semundo(unsigned long unshare_flags, struct sem_undo_list **new_ulistp)
+{
+ if (unshare_flags & CLONE_SYSVSEM)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * unshare allows a process to 'unshare' part of the process
+ * context which was originally shared using clone. copy_*
+ * functions used by do_fork() cannot be used here directly
+ * because they modify an inactive task_struct that is being
+ * constructed. Here we are modifying the current, active,
+ * task_struct.
+ */
+asmlinkage long sys_unshare(unsigned long unshare_flags)
+{
+ int err = 0;
+ struct fs_struct *fs, *new_fs = NULL;
+ struct namespace *ns, *new_ns = NULL;
+ struct sighand_struct *sigh, *new_sigh = NULL;
+ struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL;
+ struct files_struct *fd, *new_fd = NULL;
+ struct sem_undo_list *new_ulist = NULL;
+
+ check_unshare_flags(&unshare_flags);
+
+ if ((err = unshare_thread(unshare_flags)))
+ goto bad_unshare_out;
+ if ((err = unshare_fs(unshare_flags, &new_fs)))
+ goto bad_unshare_cleanup_thread;
+ if ((err = unshare_namespace(unshare_flags, &new_ns, new_fs)))
+ goto bad_unshare_cleanup_fs;
+ if ((err = unshare_sighand(unshare_flags, &new_sigh)))
+ goto bad_unshare_cleanup_ns;
+ if ((err = unshare_vm(unshare_flags, &new_mm)))
+ goto bad_unshare_cleanup_sigh;
+ if ((err = unshare_fd(unshare_flags, &new_fd)))
+ goto bad_unshare_cleanup_vm;
+ if ((err = unshare_semundo(unshare_flags, &new_ulist)))
+ goto bad_unshare_cleanup_fd;
+
+ if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist) {
+
+ task_lock(current);
+
+ if (new_fs) {
+ fs = current->fs;
+ current->fs = new_fs;
+ new_fs = fs;
+ }
+
+ if (new_ns) {
+ ns = current->namespace;
+ current->namespace = new_ns;
+ new_ns = ns;
+ }
+
+ if (new_sigh) {
+ sigh = current->sighand;
+ current->sighand = new_sigh;
+ new_sigh = sigh;
+ }
+
+ if (new_mm) {
+ mm = current->mm;
+ active_mm = current->active_mm;
+ current->mm = new_mm;
+ current->active_mm = new_mm;
+ activate_mm(active_mm, new_mm);
+ new_mm = mm;
+ }
+
+ if (new_fd) {
+ fd = current->files;
+ current->files = new_fd;
+ new_fd = fd;
+ }
+
+ task_unlock(current);
+ }
+
+bad_unshare_cleanup_fd:
+ if (new_fd)
+ put_files_struct(new_fd);
+
+bad_unshare_cleanup_vm:
+ if (new_mm)
+ mmput(new_mm);
+
+bad_unshare_cleanup_sigh:
+ if (new_sigh)
+ if (atomic_dec_and_test(&new_sigh->count))
+ kmem_cache_free(sighand_cachep, new_sigh);
+
+bad_unshare_cleanup_ns:
+ if (new_ns)
+ put_namespace(new_ns);
+
+bad_unshare_cleanup_fs:
+ if (new_fs)
+ put_fs_struct(new_fs);
+
+bad_unshare_cleanup_thread:
+bad_unshare_out:
+ return err;
+}
diff --git a/kernel/module.c b/kernel/module.c
index e058aedf6b9..5aad477ddc7 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1670,6 +1670,9 @@ static struct module *load_module(void __user *umod,
goto free_mod;
}
+ /* Userspace could have altered the string after the strlen_user() */
+ args[arglen - 1] = '\0';
+
if (find_module(mod->name)) {
err = -EEXIST;
goto free_mod;
diff --git a/kernel/power/console.c b/kernel/power/console.c
index 579d239d129..623786d4415 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -9,7 +9,9 @@
#include <linux/console.h>
#include "power.h"
-#ifdef SUSPEND_CONSOLE
+#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
+#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1)
+
static int orig_fgconsole, orig_kmsg;
int pm_prepare_console(void)
diff --git a/kernel/power/power.h b/kernel/power/power.h
index d8f0d1a76ba..388dba68084 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -1,14 +1,6 @@
#include <linux/suspend.h>
#include <linux/utsname.h>
-/* With SUSPEND_CONSOLE defined suspend looks *really* cool, but
- we probably do not take enough locks for switching consoles, etc,
- so bad things might happen.
-*/
-#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
-#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1)
-#endif
-
struct swsusp_info {
struct new_utsname uts;
u32 version_code;
@@ -42,14 +34,6 @@ static struct subsys_attribute _name##_attr = { \
extern struct subsystem power_subsys;
-#ifdef SUSPEND_CONSOLE
-extern int pm_prepare_console(void);
-extern void pm_restore_console(void);
-#else
-static int pm_prepare_console(void) { return 0; }
-static void pm_restore_console(void) {}
-#endif
-
/* References to section boundaries */
extern const void __nosave_begin, __nosave_end;
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 59c91c148e8..4e90905f0e8 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -743,7 +743,6 @@ static int submit(int rw, pgoff_t page_off, void *page)
if (!bio)
return -ENOMEM;
bio->bi_sector = page_off * (PAGE_SIZE >> 9);
- bio_get(bio);
bio->bi_bdev = resume_bdev;
bio->bi_end_io = end_io;
@@ -753,14 +752,13 @@ static int submit(int rw, pgoff_t page_off, void *page)
goto Done;
}
- if (rw == WRITE)
- bio_set_pages_dirty(bio);
atomic_set(&io_done, 1);
submit_bio(rw | (1 << BIO_RW_SYNC), bio);
while (atomic_read(&io_done))
yield();
-
+ if (rw == READ)
+ bio_set_pages_dirty(bio);
Done:
bio_put(bio);
return error;
diff --git a/kernel/signal.c b/kernel/signal.c
index b373fc2420d..ea154104a00 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2430,7 +2430,7 @@ sys_rt_sigqueueinfo(int pid, int sig, siginfo_t __user *uinfo)
}
int
-do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact)
+do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)
{
struct k_sigaction *k;
sigset_t mask;
@@ -2454,6 +2454,8 @@ do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact)
*oact = *k;
if (act) {
+ sigdelsetmask(&act->sa.sa_mask,
+ sigmask(SIGKILL) | sigmask(SIGSTOP));
/*
* POSIX 3.3.1.3:
* "Setting a signal action to SIG_IGN for a signal that is
@@ -2479,8 +2481,6 @@ do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact)
read_lock(&tasklist_lock);
spin_lock_irq(&t->sighand->siglock);
*k = *act;
- sigdelsetmask(&k->sa.sa_mask,
- sigmask(SIGKILL) | sigmask(SIGSTOP));
sigemptyset(&mask);
sigaddset(&mask, sig);
rm_from_queue_full(&mask, &t->signal->shared_pending);
@@ -2495,8 +2495,6 @@ do_sigaction(int sig, const struct k_sigaction *act, struct k_sigaction *oact)
}
*k = *act;
- sigdelsetmask(&k->sa.sa_mask,
- sigmask(SIGKILL) | sigmask(SIGSTOP));
}
spin_unlock_irq(&current->sighand->siglock);
@@ -2702,6 +2700,7 @@ sys_signal(int sig, __sighandler_t handler)
new_sa.sa.sa_handler = handler;
new_sa.sa.sa_flags = SA_ONESHOT | SA_NOMASK;
+ sigemptyset(&new_sa.sa.sa_mask);
ret = do_sigaction(sig, &new_sa, &old_sa);
diff --git a/kernel/sys.c b/kernel/sys.c
index 0929c698aff..f91218a5463 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -428,7 +428,7 @@ void kernel_kexec(void)
{
#ifdef CONFIG_KEXEC
struct kimage *image;
- image = xchg(&kexec_image, 0);
+ image = xchg(&kexec_image, NULL);
if (!image) {
return;
}
diff --git a/kernel/timer.c b/kernel/timer.c
index 4f1cb0ab525..b9dad399467 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -495,7 +495,7 @@ unsigned long next_timer_interrupt(void)
base = &__get_cpu_var(tvec_bases);
spin_lock(&base->t_base.lock);
expires = base->timer_jiffies + (LONG_MAX >> 1);
- list = 0;
+ list = NULL;
/* Look for timer events in tv1. */
j = base->timer_jiffies & TVR_MASK;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-17 17:54:16 +0000