This patch defines kernel_read_file_from_fd(), a wrapper for the VFS
common kernel_read_file().
Changelog:
- Separated from the kernel modules patch
Acked-by: Kees Cook <keescook at chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof at kernel.org>
Cc: Al Viro <viro at zeniv.linux.org.uk>
Signed-off-by: Mimi Zohar <zohar at linux.vnet.ibm.com>
---
fs/exec.c | 16 ++++++++++++++++
include/linux/fs.h | 2 ++
2 files changed, 18 insertions(+)
diff --git a/fs/exec.c b/fs/exec.c
index 78dfdf3..604f669 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -910,6 +910,22 @@ int kernel_read_file_from_path(char *path, void **buf, loff_t *size,
}
EXPORT_SYMBOL_GPL(kernel_read_file_from_path);
+int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size,
+ enum kernel_read_file_id id)
+{
+ struct fd f = fdget(fd);
+ int ret = -EBADF;
+
+ if (!f.file)
+ goto out;
+
+ ret = kernel_read_file(f.file, buf, size, max_size, id);
+out:
+ fdput(f);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(kernel_read_file_from_fd);
+
ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
{
ssize_t res = vfs_read(file, (void __user *)addr, len, &pos);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index c8bc4d8..9c85dea 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2586,6 +2586,8 @@ extern int kernel_read_file(struct file *, void **, loff_t *, loff_t,
enum kernel_read_file_id);
extern int kernel_read_file_from_path(char *, void **, loff_t *, loff_t,
enum kernel_read_file_id);
+extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t,
+ enum kernel_read_file_id);
extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
extern struct file * open_exec(const char *);
--
2.1.0
