1 files changed, 24 insertions, 11 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index d53246863cfb..1a76d751cf3c 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -261,7 +261,7 @@ static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
 	 * Inherently racy -- command line shares address space
 	 * with code and data.
 	 */
-	rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0);
+	rv = access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON);
 	if (rv <= 0)
 		goto out_free_page;
 
@@ -279,7 +279,7 @@ static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
 			int nr_read;
 
 			_count = min3(count, len, PAGE_SIZE);
-			nr_read = access_remote_vm(mm, p, page, _count, 0);
+			nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
 			if (nr_read < 0)
 				rv = nr_read;
 			if (nr_read <= 0)
@@ -325,7 +325,7 @@ static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
 				bool final;
 
 				_count = min3(count, len, PAGE_SIZE);
-				nr_read = access_remote_vm(mm, p, page, _count, 0);
+				nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
 				if (nr_read < 0)
 					rv = nr_read;
 				if (nr_read <= 0)
@@ -388,14 +388,17 @@ static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
 	unsigned long wchan;
 	char symname[KSYM_NAME_LEN];
 
-	wchan = get_wchan(task);
+	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
+		goto print0;
 
-	if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)
-			&& !lookup_symbol_name(wchan, symname))
-		seq_printf(m, "%s", symname);
-	else
-		seq_putc(m, '0');
+	wchan = get_wchan(task);
+	if (wchan && !lookup_symbol_name(wchan, symname)) {
+		seq_puts(m, symname);
+		return 0;
+	}
 
+print0:
+	seq_putc(m, '0');
 	return 0;
 }
 #endif /* CONFIG_KALLSYMS */
@@ -943,7 +946,7 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 		max_len = min_t(size_t, PAGE_SIZE, count);
 		this_len = min(max_len, this_len);
 
-		retval = access_remote_vm(mm, (env_start + src), page, this_len, 0);
+		retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);
 
 		if (retval <= 0) {
 			ret = retval;
@@ -1690,6 +1693,12 @@ void task_dump_owner(struct task_struct *task, umode_t mode,
 	kuid_t uid;
 	kgid_t gid;
 
+	if (unlikely(task->flags & PF_KTHREAD)) {
+		*ruid = GLOBAL_ROOT_UID;
+		*rgid = GLOBAL_ROOT_GID;
+		return;
+	}
+
 	/* Default to the tasks effective ownership */
 	rcu_read_lock();
 	cred = __task_cred(task);
@@ -1910,6 +1919,8 @@ static int dname_to_vma_addr(struct dentry *dentry,
 	unsigned long long sval, eval;
 	unsigned int len;
 
+	if (str[0] == '0' && str[1] != '-')
+		return -EINVAL;
 	len = _parse_integer(str, 16, &sval);
 	if (len & KSTRTOX_OVERFLOW)
 		return -EINVAL;
@@ -1921,6 +1932,8 @@ static int dname_to_vma_addr(struct dentry *dentry,
 		return -EINVAL;
 	str++;
 
+	if (str[0] == '0' && str[1])
+		return -EINVAL;
 	len = _parse_integer(str, 16, &eval);
 	if (len & KSTRTOX_OVERFLOW)
 		return -EINVAL;
@@ -2204,6 +2217,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
 		}
 	}
 	up_read(&mm->mmap_sem);
+	mmput(mm);
 
 	for (i = 0; i < nr_files; i++) {
 		char buf[4 * sizeof(long) + 2];	/* max: %lx-%lx\0 */
@@ -2221,7 +2235,6 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
 	}
 	if (fa)
 		flex_array_free(fa);
-	mmput(mm);
 
 out_put_task:
 	put_task_struct(task);