[PATCH v3 2/2] fs: avoid fdput() after failed fdget() in kernel_read_file_from_fd()

From: Shuah Khan
Date: Wed May 13 2020 - 19:33:33 EST


Fix kernel_read_file_from_fd() to avoid fdput() after a failed fdget().
fdput() doesn't do fput() on this file since FDPUT_FPUT isn't set
in fd.flags. Fix it anyway since failed fdget() doesn't require
a fdput().

This was introduced in a commit that added kernel_read_file_from_fd() as
a wrapper for the VFS common kernel_read_file().

Fixes: b844f0ecbc56 ("vfs: define kernel_copy_file_from_fd()")
Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
---
fs/exec.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index 06b4c550af5d..16a3d3192d6a 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1015,14 +1015,14 @@ 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;
+ int ret;

if (!f.file)
- goto out;
+ return -EBADF;

ret = kernel_read_file(f.file, buf, size, max_size, id);
-out:
fdput(f);
+
return ret;
}
EXPORT_SYMBOL_GPL(kernel_read_file_from_fd);
--
2.25.1