From 41535701da3324b80029cabb501e86c4fafe339d Mon Sep 17 00:00:00 2001 From: Rohith Surabattula Date: Thu, 29 Jul 2021 07:45:29 +0000 Subject: cifs: Handle race conditions during rename When rename is executed on directory which has files for which close is deferred, then rename will fail with EACCES. This patch will try to close all deferred files when EACCES is received and retry rename on a directory. Signed-off-by: Rohith Surabattula Cc: stable@vger.kernel.org # 5.13 Reviewed-by: Shyam Prasad N Signed-off-by: Steve French --- fs/cifs/misc.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'fs/cifs/misc.c') diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c index 844abeb2b48f..cdb1ec1461de 100644 --- a/fs/cifs/misc.c +++ b/fs/cifs/misc.c @@ -723,13 +723,19 @@ void cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode) { struct cifsFileInfo *cfile = NULL; - struct cifs_deferred_close *dclose; + + if (cifs_inode == NULL) + return; list_for_each_entry(cfile, &cifs_inode->openFileList, flist) { - spin_lock(&cifs_inode->deferred_lock); - if (cifs_is_deferred_close(cfile, &dclose)) - mod_delayed_work(deferredclose_wq, &cfile->deferred, 0); - spin_unlock(&cifs_inode->deferred_lock); + if (delayed_work_pending(&cfile->deferred)) { + /* + * If there is no pending work, mod_delayed_work queues new work. + * So, Increase the ref count to avoid use-after-free. + */ + if (!mod_delayed_work(deferredclose_wq, &cfile->deferred, 0)) + cifsFileInfo_get(cfile); + } } } -- cgit v1.2.3