4 files changed, 60 insertions, 11 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index ddef482f1334..6a803a0b75df 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -616,24 +616,25 @@ static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
 			    struct pid *pid, struct task_struct *task)
 {
-	long nr;
-	unsigned long args[6], sp, pc;
+	struct syscall_info info;
+	u64 *args = &info.data.args[0];
 	int res;
 
 	res = lock_trace(task);
 	if (res)
 		return res;
 
-	if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
+	if (task_current_syscall(task, &info))
 		seq_puts(m, "running\n");
-	else if (nr < 0)
-		seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
+	else if (info.data.nr < 0)
+		seq_printf(m, "%d 0x%llx 0x%llx\n",
+			   info.data.nr, info.sp, info.data.instruction_pointer);
 	else
 		seq_printf(m,
-		       "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
-		       nr,
+		       "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",
+		       info.data.nr,
 		       args[0], args[1], args[2], args[3], args[4], args[5],
-		       sp, pc);
+		       info.sp, info.data.instruction_pointer);
 	unlock_trace(task);
 
 	return 0;
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index bbcc185062bb..f5834488b67d 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -54,6 +54,28 @@ static LIST_HEAD(kclist_head);
 static DECLARE_RWSEM(kclist_lock);
 static int kcore_need_update = 1;
 
+/*
+ * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error
+ * Same as oldmem_pfn_is_ram in vmcore
+ */
+static int (*mem_pfn_is_ram)(unsigned long pfn);
+
+int __init register_mem_pfn_is_ram(int (*fn)(unsigned long pfn))
+{
+	if (mem_pfn_is_ram)
+		return -EBUSY;
+	mem_pfn_is_ram = fn;
+	return 0;
+}
+
+static int pfn_is_ram(unsigned long pfn)
+{
+	if (mem_pfn_is_ram)
+		return mem_pfn_is_ram(pfn);
+	else
+		return 1;
+}
+
 /* This doesn't grab kclist_lock, so it should only be used at init time. */
 void __init kclist_add(struct kcore_list *new, void *addr, size_t size,
 		       int type)
@@ -465,6 +487,11 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
 				goto out;
 			}
 			m = NULL;	/* skip the list anchor */
+		} else if (!pfn_is_ram(__pa(start) >> PAGE_SHIFT)) {
+			if (clear_user(buffer, tsz)) {
+				ret = -EFAULT;
+				goto out;
+			}
 		} else if (m->type == KCORE_VMALLOC) {
 			vread(buf, (char *)start, tsz);
 			/* we have to zero-fill user buffer even if no read */
@@ -588,7 +615,7 @@ static void __init proc_kcore_text_init(void)
 /*
  * MODULES_VADDR has no intersection with VMALLOC_ADDR.
  */
-struct kcore_list kcore_modules;
+static struct kcore_list kcore_modules;
 static void __init add_modules_range(void)
 {
 	if (MODULES_VADDR != VMALLOC_START && MODULES_END != VMALLOC_END) {
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 4d598a399bbf..7325baa8f9d4 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -1626,8 +1626,11 @@ static void drop_sysctl_table(struct ctl_table_header *header)
 	if (--header->nreg)
 		return;
 
-	put_links(header);
-	start_unregistering(header);
+	if (parent) {
+		put_links(header);
+		start_unregistering(header);
+	}
+
 	if (!--header->count)
 		kfree_rcu(header, rcu);
 
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 92a91e7816d8..95ca1fe7283c 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1143,6 +1143,24 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
 					count = -EINTR;
 					goto out_mm;
 				}
+				/*
+				 * Avoid to modify vma->vm_flags
+				 * without locked ops while the
+				 * coredump reads the vm_flags.
+				 */
+				if (!mmget_still_valid(mm)) {
+					/*
+					 * Silently return "count"
+					 * like if get_task_mm()
+					 * failed. FIXME: should this
+					 * function have returned
+					 * -ESRCH if get_task_mm()
+					 * failed like if
+					 * get_proc_task() fails?
+					 */
+					up_write(&mm->mmap_sem);
+					goto out_mm;
+				}
 				for (vma = mm->mmap; vma; vma = vma->vm_next) {
 					vma->vm_flags &= ~VM_SOFTDIRTY;
 					vma_set_page_prot(vma);