| From 81c99089bce693b94b775b6eb888115d2d540086 Mon Sep 17 00:00:00 2001 |
| From: Dominique Martinet <dominique.martinet@cea.fr> |
| Date: Mon, 27 Aug 2018 15:12:05 +0900 |
| Subject: v9fs_dir_readdir: fix double-free on p9stat_read error |
| |
| From: Dominique Martinet <dominique.martinet@cea.fr> |
| |
| commit 81c99089bce693b94b775b6eb888115d2d540086 upstream. |
| |
| p9stat_read will call p9stat_free on error, we should only free the |
| struct content on success. |
| |
| There also is no need to "p9stat_init" st as the read function will |
| zero the whole struct for us anyway, so clean up the code a bit while |
| we are here. |
| |
| Link: http://lkml.kernel.org/r/1535410108-20650-1-git-send-email-asmadeus@codewreck.org |
| Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr> |
| Reported-by: syzbot+d4252148d198410b864f@syzkaller.appspotmail.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| fs/9p/vfs_dir.c | 11 ----------- |
| 1 file changed, 11 deletions(-) |
| |
| --- a/fs/9p/vfs_dir.c |
| +++ b/fs/9p/vfs_dir.c |
| @@ -76,15 +76,6 @@ static inline int dt_type(struct p9_wsta |
| return rettype; |
| } |
| |
| -static void p9stat_init(struct p9_wstat *stbuf) |
| -{ |
| - stbuf->name = NULL; |
| - stbuf->uid = NULL; |
| - stbuf->gid = NULL; |
| - stbuf->muid = NULL; |
| - stbuf->extension = NULL; |
| -} |
| - |
| /** |
| * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir |
| * @filp: opened file structure |
| @@ -145,12 +136,10 @@ static int v9fs_dir_readdir(struct file |
| rdir->tail = n; |
| } |
| while (rdir->head < rdir->tail) { |
| - p9stat_init(&st); |
| err = p9stat_read(fid->clnt, rdir->buf + rdir->head, |
| rdir->tail - rdir->head, &st); |
| if (err) { |
| p9_debug(P9_DEBUG_VFS, "returned %d\n", err); |
| - p9stat_free(&st); |
| return -EIO; |
| } |
| reclen = st.size+2; |