Re: [syzbot] [v9fs?] UBSAN: shift-out-of-bounds in v9fs_get_tree

[Edward Adam Davis]

#syz test

diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index f6065b5e0e5d..cc2056dd0bef 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -50,7 +50,7 @@ static int v9fs_fill_super(struct super_block *sb, struct fs_context *fc)
 {
 	int ret;
 	struct v9fs_context	*ctx = fc->fs_private;
-	struct v9fs_session_info *v9ses = &ctx->v9ses;
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
 
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
 	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);