[PATCH 5.17 768/772] fs/ntfs3: Fix invalid free in log_replay

Greg Kroah-Hartman
2022-06-07T21:54:50Z

From: Namjae Jeon <linkinjeon@kernel.org>

commit f26967b9f7a830e228bb13fb41bd516ddd9d789d upstream.

log_read_rst() returns ENOMEM error when there is not enough memory.
In this case, if info is returned without initialization,
it attempts to kfree the uninitialized info->r_page pointer. This patch
moves the memset initialization code to before log_read_rst() is called.

Reported-by: Gerald Lee <sundaywind2004@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ntfs3/fslog.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -1185,8 +1185,6 @@ static int log_read_rst(struct ntfs_log
if (!r_page)
return -ENOMEM;

- memset(info, 0, sizeof(struct restart_info));
-
/* Determine which restart area we are looking for. */
if (first) {
vbo = 0;
@@ -3791,10 +3789,11 @@ int log_replay(struct ntfs_inode *ni, bo
if (!log)
return -ENOMEM;

+ memset(&rst_info, 0, sizeof(struct restart_info));
+
log->ni = ni;
log->l_size = l_size;
log->one_page_buf = kmalloc(page_size, GFP_NOFS);
-
if (!log->one_page_buf) {
err = -ENOMEM;
goto out;
@@ -3842,6 +3841,7 @@ int log_replay(struct ntfs_inode *ni, bo
if (rst_info.vbo)
goto check_restart_area;

+ memset(&rst_info2, 0, sizeof(struct restart_info));
err = log_read_rst(log, l_size, false, &rst_info2);

/* Determine which restart area to use. */