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-rw-r--r--kernel/exit.c6
-rw-r--r--kernel/kexec.c25
-rw-r--r--kernel/kprobes.c2
-rw-r--r--kernel/panic.c26
-rw-r--r--kernel/pid.c4
-rw-r--r--kernel/pid_namespace.c31
-rw-r--r--kernel/sys.c121
7 files changed, 200 insertions, 15 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 94ed6e20bb5..c44738267be 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -887,7 +887,7 @@ static void check_stack_usage(void)
static inline void check_stack_usage(void) {}
#endif
-NORET_TYPE void do_exit(long code)
+void do_exit(long code)
{
struct task_struct *tsk = current;
int group_dead;
@@ -1051,7 +1051,7 @@ NORET_TYPE void do_exit(long code)
EXPORT_SYMBOL_GPL(do_exit);
-NORET_TYPE void complete_and_exit(struct completion *comp, long code)
+void complete_and_exit(struct completion *comp, long code)
{
if (comp)
complete(comp);
@@ -1070,7 +1070,7 @@ SYSCALL_DEFINE1(exit, int, error_code)
* Take down every thread in the group. This is called by fatal signals
* as well as by sys_exit_group (below).
*/
-NORET_TYPE void
+void
do_group_exit(int exit_code)
{
struct signal_struct *sig = current->signal;
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 090ee10d960..7b088678670 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -32,7 +32,6 @@
#include <linux/console.h>
#include <linux/vmalloc.h>
#include <linux/swap.h>
-#include <linux/kmsg_dump.h>
#include <linux/syscore_ops.h>
#include <asm/page.h>
@@ -1094,8 +1093,6 @@ void crash_kexec(struct pt_regs *regs)
if (kexec_crash_image) {
struct pt_regs fixed_regs;
- kmsg_dump(KMSG_DUMP_KEXEC);
-
crash_setup_regs(&fixed_regs, regs);
crash_save_vmcoreinfo();
machine_crash_shutdown(&fixed_regs);
@@ -1132,6 +1129,8 @@ int crash_shrink_memory(unsigned long new_size)
{
int ret = 0;
unsigned long start, end;
+ unsigned long old_size;
+ struct resource *ram_res;
mutex_lock(&kexec_mutex);
@@ -1141,11 +1140,15 @@ int crash_shrink_memory(unsigned long new_size)
}
start = crashk_res.start;
end = crashk_res.end;
+ old_size = (end == 0) ? 0 : end - start + 1;
+ if (new_size >= old_size) {
+ ret = (new_size == old_size) ? 0 : -EINVAL;
+ goto unlock;
+ }
- if (new_size >= end - start + 1) {
- ret = -EINVAL;
- if (new_size == end - start + 1)
- ret = 0;
+ ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
+ if (!ram_res) {
+ ret = -ENOMEM;
goto unlock;
}
@@ -1157,7 +1160,15 @@ int crash_shrink_memory(unsigned long new_size)
if ((start == end) && (crashk_res.parent != NULL))
release_resource(&crashk_res);
+
+ ram_res->start = end;
+ ram_res->end = crashk_res.end;
+ ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
+ ram_res->name = "System RAM";
+
crashk_res.end = end - 1;
+
+ insert_resource(&iomem_resource, ram_res);
crash_unmap_reserved_pages();
unlock:
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index e5d84644823..95dd7212e61 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2198,7 +2198,7 @@ static ssize_t write_enabled_file_bool(struct file *file,
const char __user *user_buf, size_t count, loff_t *ppos)
{
char buf[32];
- int buf_size;
+ size_t buf_size;
buf_size = min(count, (sizeof(buf)-1));
if (copy_from_user(buf, user_buf, buf_size))
diff --git a/kernel/panic.c b/kernel/panic.c
index 3458469eb7c..80aed44e345 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -49,6 +49,15 @@ static long no_blink(int state)
long (*panic_blink)(int state);
EXPORT_SYMBOL(panic_blink);
+/*
+ * Stop ourself in panic -- architecture code may override this
+ */
+void __weak panic_smp_self_stop(void)
+{
+ while (1)
+ cpu_relax();
+}
+
/**
* panic - halt the system
* @fmt: The text string to print
@@ -57,8 +66,9 @@ EXPORT_SYMBOL(panic_blink);
*
* This function never returns.
*/
-NORET_TYPE void panic(const char * fmt, ...)
+void panic(const char *fmt, ...)
{
+ static DEFINE_SPINLOCK(panic_lock);
static char buf[1024];
va_list args;
long i, i_next = 0;
@@ -68,8 +78,14 @@ NORET_TYPE void panic(const char * fmt, ...)
* It's possible to come here directly from a panic-assertion and
* not have preempt disabled. Some functions called from here want
* preempt to be disabled. No point enabling it later though...
+ *
+ * Only one CPU is allowed to execute the panic code from here. For
+ * multiple parallel invocations of panic, all other CPUs either
+ * stop themself or will wait until they are stopped by the 1st CPU
+ * with smp_send_stop().
*/
- preempt_disable();
+ if (!spin_trylock(&panic_lock))
+ panic_smp_self_stop();
console_verbose();
bust_spinlocks(1);
@@ -78,7 +94,11 @@ NORET_TYPE void panic(const char * fmt, ...)
va_end(args);
printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
#ifdef CONFIG_DEBUG_BUGVERBOSE
- dump_stack();
+ /*
+ * Avoid nested stack-dumping if a panic occurs during oops processing
+ */
+ if (!oops_in_progress)
+ dump_stack();
#endif
/*
diff --git a/kernel/pid.c b/kernel/pid.c
index fa5f72227e5..ce8e00deacc 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -137,7 +137,9 @@ static int pid_before(int base, int a, int b)
}
/*
- * We might be racing with someone else trying to set pid_ns->last_pid.
+ * We might be racing with someone else trying to set pid_ns->last_pid
+ * at the pid allocation time (there's also a sysctl for this, but racing
+ * with this one is OK, see comment in kernel/pid_namespace.c about it).
* We want the winner to have the "later" value, because if the
* "earlier" value prevails, then a pid may get reused immediately.
*
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index e9c9adc84ca..a8968396046 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -191,9 +191,40 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
return;
}
+static int pid_ns_ctl_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table tmp = *table;
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /*
+ * Writing directly to ns' last_pid field is OK, since this field
+ * is volatile in a living namespace anyway and a code writing to
+ * it should synchronize its usage with external means.
+ */
+
+ tmp.data = &current->nsproxy->pid_ns->last_pid;
+ return proc_dointvec(&tmp, write, buffer, lenp, ppos);
+}
+
+static struct ctl_table pid_ns_ctl_table[] = {
+ {
+ .procname = "ns_last_pid",
+ .maxlen = sizeof(int),
+ .mode = 0666, /* permissions are checked in the handler */
+ .proc_handler = pid_ns_ctl_handler,
+ },
+ { }
+};
+
+static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } };
+
static __init int pid_namespaces_init(void)
{
pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC);
+ register_sysctl_paths(kern_path, pid_ns_ctl_table);
return 0;
}
diff --git a/kernel/sys.c b/kernel/sys.c
index ddf8155bf3f..40701538fbd 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1692,6 +1692,124 @@ SYSCALL_DEFINE1(umask, int, mask)
return mask;
}
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int prctl_set_mm(int opt, unsigned long addr,
+ unsigned long arg4, unsigned long arg5)
+{
+ unsigned long rlim = rlimit(RLIMIT_DATA);
+ unsigned long vm_req_flags;
+ unsigned long vm_bad_flags;
+ struct vm_area_struct *vma;
+ int error = 0;
+ struct mm_struct *mm = current->mm;
+
+ if (arg4 | arg5)
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (addr >= TASK_SIZE)
+ return -EINVAL;
+
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, addr);
+
+ if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) {
+ /* It must be existing VMA */
+ if (!vma || vma->vm_start > addr)
+ goto out;
+ }
+
+ error = -EINVAL;
+ switch (opt) {
+ case PR_SET_MM_START_CODE:
+ case PR_SET_MM_END_CODE:
+ vm_req_flags = VM_READ | VM_EXEC;
+ vm_bad_flags = VM_WRITE | VM_MAYSHARE;
+
+ if ((vma->vm_flags & vm_req_flags) != vm_req_flags ||
+ (vma->vm_flags & vm_bad_flags))
+ goto out;
+
+ if (opt == PR_SET_MM_START_CODE)
+ mm->start_code = addr;
+ else
+ mm->end_code = addr;
+ break;
+
+ case PR_SET_MM_START_DATA:
+ case PR_SET_MM_END_DATA:
+ vm_req_flags = VM_READ | VM_WRITE;
+ vm_bad_flags = VM_EXEC | VM_MAYSHARE;
+
+ if ((vma->vm_flags & vm_req_flags) != vm_req_flags ||
+ (vma->vm_flags & vm_bad_flags))
+ goto out;
+
+ if (opt == PR_SET_MM_START_DATA)
+ mm->start_data = addr;
+ else
+ mm->end_data = addr;
+ break;
+
+ case PR_SET_MM_START_STACK:
+
+#ifdef CONFIG_STACK_GROWSUP
+ vm_req_flags = VM_READ | VM_WRITE | VM_GROWSUP;
+#else
+ vm_req_flags = VM_READ | VM_WRITE | VM_GROWSDOWN;
+#endif
+ if ((vma->vm_flags & vm_req_flags) != vm_req_flags)
+ goto out;
+
+ mm->start_stack = addr;
+ break;
+
+ case PR_SET_MM_START_BRK:
+ if (addr <= mm->end_data)
+ goto out;
+
+ if (rlim < RLIM_INFINITY &&
+ (mm->brk - addr) +
+ (mm->end_data - mm->start_data) > rlim)
+ goto out;
+
+ mm->start_brk = addr;
+ break;
+
+ case PR_SET_MM_BRK:
+ if (addr <= mm->end_data)
+ goto out;
+
+ if (rlim < RLIM_INFINITY &&
+ (addr - mm->start_brk) +
+ (mm->end_data - mm->start_data) > rlim)
+ goto out;
+
+ mm->brk = addr;
+ break;
+
+ default:
+ error = -EINVAL;
+ goto out;
+ }
+
+ error = 0;
+
+out:
+ up_read(&mm->mmap_sem);
+
+ return error;
+}
+#else /* CONFIG_CHECKPOINT_RESTORE */
+static int prctl_set_mm(int opt, unsigned long addr,
+ unsigned long arg4, unsigned long arg5)
+{
+ return -EINVAL;
+}
+#endif
+
SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
unsigned long, arg4, unsigned long, arg5)
{
@@ -1841,6 +1959,9 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
else
error = PR_MCE_KILL_DEFAULT;
break;
+ case PR_SET_MM:
+ error = prctl_set_mm(arg2, arg3, arg4, arg5);
+ break;
default:
error = -EINVAL;
break;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-29 01:24:22 +0000