From: Chao Yu Date: Sun, 28 Aug 2016 14:00:12 +0000 (+0800) Subject: f2fs crypto: avoid unneeded memory allocation in ->readdir X-Git-Tag: v4.4.242~77 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5ca3fb31d499b4811deeabbf7b3dc5f867f9a6aa;p=thirdparty%2Fkernel%2Fstable.git f2fs crypto: avoid unneeded memory allocation in ->readdir commit e06f86e61d7a67fe6e826010f57aa39c674f4b1b upstream. When decrypting dirents in ->readdir, fscrypt_fname_disk_to_usr won't change content of original encrypted dirent, we don't need to allocate additional buffer for storing mirror of it, so get rid of it. [This backport fixes a regression in 4.4-stable caused by commit 11a6e8f89521 ("f2fs: check memory boundary by insane namelen"), which depended on this missing commit. This bad backport broke f2fs encryption because it moved the incrementing of 'bit_pos' to earlier in f2fs_fill_dentries() without accounting for it being used in the encrypted dir case. This caused readdir() on encrypted directories to start failing. Tested with 'kvm-xfstests -c f2fs -g encrypt'.] Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index e2ff0eb16f89c..c1130914d6ed7 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -820,15 +820,8 @@ bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, int save_len = fstr->len; int ret; - de_name.name = kmalloc(de_name.len, GFP_NOFS); - if (!de_name.name) - return false; - - memcpy(de_name.name, d->filename[bit_pos], de_name.len); - ret = f2fs_fname_disk_to_usr(d->inode, &de->hash_code, &de_name, fstr); - kfree(de_name.name); if (ret < 0) return true;