Zheng Liang 286f94453f ovl: fix missing negative dentry check in ovl_rename() ... commit a295aef603 upstream. The following reproducer mkdir lower upper work merge touch lower/old touch lower/new mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=work merge rm merge/new mv merge/old merge/new & unlink upper/new may result in this race: PROCESS A: rename("merge/old", "merge/new"); overwrite=true,ovl_lower_positive(old)=true, ovl_dentry_is_whiteout(new)=true -> flags |= RENAME_EXCHANGE PROCESS B: unlink("upper/new"); PROCESS A: lookup newdentry in new_upperdir call vfs_rename() with negative newdentry and RENAME_EXCHANGE Fix by adding the missing check for negative newdentry. Signed-off-by: Zheng Liang <zhengliang6@huawei.com> Fixes: e9be9d5e76 ("overlay filesystem") Cc: <stable@vger.kernel.org> # v3.18 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-10-17 10:05:38 +02:00
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Kconfig	…
Makefile	…
copy_up.c	ovl: skip getxattr of security labels	2021-02-23 13:59:15 +01:00
dir.c	ovl: fix missing negative dentry check in ovl_rename()	2021-10-17 10:05:38 +02:00
inode.c	ovl: filter of trusted xattr results in audit	2019-10-05 12:30:34 +02:00
overlayfs.h	fs: rename "rename2" i_op to "rename"	2016-09-27 11:03:58 +02:00
readdir.c	ovl: fix failure to fsync lower dir	2018-02-17 13:21:20 +01:00
super.c	ovl: fix random return value on mount	2017-07-27 15:08:07 -07:00