6.1-stable review patch. If anyone has any objections, please let me know.
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From: Ritvik Budhiraja rbudhiraja@microsoft.com
commit 173217bd73365867378b5e75a86f0049e1069ee8 upstream.
In the current implementation, CIFS close sends a close to the server and does not check for the success of the server close. This patch adds functionality to check for server close return status and retries in case of an EBUSY or EAGAIN error.
This can help avoid handle leaks
Cc: stable@vger.kernel.org Signed-off-by: Ritvik Budhiraja rbudhiraja@microsoft.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/client/cached_dir.c | 6 ++-- fs/smb/client/cifsfs.c | 11 +++++++ fs/smb/client/cifsglob.h | 7 +++-- fs/smb/client/file.c | 63 ++++++++++++++++++++++++++++++++++++++++----- fs/smb/client/smb1ops.c | 4 +- fs/smb/client/smb2ops.c | 9 +++--- fs/smb/client/smb2pdu.c | 2 - 7 files changed, 85 insertions(+), 17 deletions(-)
--- a/fs/smb/client/cached_dir.c +++ b/fs/smb/client/cached_dir.c @@ -370,6 +370,7 @@ smb2_close_cached_fid(struct kref *ref) { struct cached_fid *cfid = container_of(ref, struct cached_fid, refcount); + int rc;
spin_lock(&cfid->cfids->cfid_list_lock); if (cfid->on_list) { @@ -383,9 +384,10 @@ smb2_close_cached_fid(struct kref *ref) cfid->dentry = NULL;
if (cfid->is_open) { - SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, + rc = SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, cfid->fid.volatile_fid); - atomic_dec(&cfid->tcon->num_remote_opens); + if (rc != -EBUSY && rc != -EAGAIN) + atomic_dec(&cfid->tcon->num_remote_opens); }
free_cached_dir(cfid); --- a/fs/smb/client/cifsfs.c +++ b/fs/smb/client/cifsfs.c @@ -154,6 +154,7 @@ struct workqueue_struct *decrypt_wq; struct workqueue_struct *fileinfo_put_wq; struct workqueue_struct *cifsoplockd_wq; struct workqueue_struct *deferredclose_wq; +struct workqueue_struct *serverclose_wq; __u32 cifs_lock_secret;
/* @@ -1866,6 +1867,13 @@ init_cifs(void) goto out_destroy_cifsoplockd_wq; }
+ serverclose_wq = alloc_workqueue("serverclose", + WQ_FREEZABLE|WQ_MEM_RECLAIM, 0); + if (!serverclose_wq) { + rc = -ENOMEM; + goto out_destroy_serverclose_wq; + } + rc = cifs_init_inodecache(); if (rc) goto out_destroy_deferredclose_wq; @@ -1940,6 +1948,8 @@ out_destroy_decrypt_wq: destroy_workqueue(decrypt_wq); out_destroy_cifsiod_wq: destroy_workqueue(cifsiod_wq); +out_destroy_serverclose_wq: + destroy_workqueue(serverclose_wq); out_clean_proc: cifs_proc_clean(); return rc; @@ -1969,6 +1979,7 @@ exit_cifs(void) destroy_workqueue(cifsoplockd_wq); destroy_workqueue(decrypt_wq); destroy_workqueue(fileinfo_put_wq); + destroy_workqueue(serverclose_wq); destroy_workqueue(cifsiod_wq); cifs_proc_clean(); } --- a/fs/smb/client/cifsglob.h +++ b/fs/smb/client/cifsglob.h @@ -389,10 +389,10 @@ struct smb_version_operations { /* set fid protocol-specific info */ void (*set_fid)(struct cifsFileInfo *, struct cifs_fid *, __u32); /* close a file */ - void (*close)(const unsigned int, struct cifs_tcon *, + int (*close)(const unsigned int, struct cifs_tcon *, struct cifs_fid *); /* close a file, returning file attributes and timestamps */ - void (*close_getattr)(const unsigned int xid, struct cifs_tcon *tcon, + int (*close_getattr)(const unsigned int xid, struct cifs_tcon *tcon, struct cifsFileInfo *pfile_info); /* send a flush request to the server */ int (*flush)(const unsigned int, struct cifs_tcon *, struct cifs_fid *); @@ -1359,6 +1359,7 @@ struct cifsFileInfo { bool invalidHandle:1; /* file closed via session abend */ bool swapfile:1; bool oplock_break_cancelled:1; + bool offload:1; /* offload final part of _put to a wq */ unsigned int oplock_epoch; /* epoch from the lease break */ __u32 oplock_level; /* oplock/lease level from the lease break */ int count; @@ -1367,6 +1368,7 @@ struct cifsFileInfo { struct cifs_search_info srch_inf; struct work_struct oplock_break; /* work for oplock breaks */ struct work_struct put; /* work for the final part of _put */ + struct work_struct serverclose; /* work for serverclose */ struct delayed_work deferred; bool deferred_close_scheduled; /* Flag to indicate close is scheduled */ char *symlink_target; @@ -2005,6 +2007,7 @@ extern struct workqueue_struct *decrypt_ extern struct workqueue_struct *fileinfo_put_wq; extern struct workqueue_struct *cifsoplockd_wq; extern struct workqueue_struct *deferredclose_wq; +extern struct workqueue_struct *serverclose_wq; extern __u32 cifs_lock_secret;
extern mempool_t *cifs_mid_poolp; --- a/fs/smb/client/file.c +++ b/fs/smb/client/file.c @@ -330,6 +330,7 @@ cifs_down_write(struct rw_semaphore *sem }
static void cifsFileInfo_put_work(struct work_struct *work); +void serverclose_work(struct work_struct *work);
struct cifsFileInfo *cifs_new_fileinfo(struct cifs_fid *fid, struct file *file, struct tcon_link *tlink, __u32 oplock, @@ -376,6 +377,7 @@ struct cifsFileInfo *cifs_new_fileinfo(s cfile->tlink = cifs_get_tlink(tlink); INIT_WORK(&cfile->oplock_break, cifs_oplock_break); INIT_WORK(&cfile->put, cifsFileInfo_put_work); + INIT_WORK(&cfile->serverclose, serverclose_work); INIT_DELAYED_WORK(&cfile->deferred, smb2_deferred_work_close); mutex_init(&cfile->fh_mutex); spin_lock_init(&cfile->file_info_lock); @@ -467,6 +469,40 @@ static void cifsFileInfo_put_work(struct cifsFileInfo_put_final(cifs_file); }
+void serverclose_work(struct work_struct *work) +{ + struct cifsFileInfo *cifs_file = container_of(work, + struct cifsFileInfo, serverclose); + + struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink); + + struct TCP_Server_Info *server = tcon->ses->server; + int rc = 0; + int retries = 0; + int MAX_RETRIES = 4; + + do { + if (server->ops->close_getattr) + rc = server->ops->close_getattr(0, tcon, cifs_file); + else if (server->ops->close) + rc = server->ops->close(0, tcon, &cifs_file->fid); + + if (rc == -EBUSY || rc == -EAGAIN) { + retries++; + msleep(250); + } + } while ((rc == -EBUSY || rc == -EAGAIN) && (retries < MAX_RETRIES) + ); + + if (retries == MAX_RETRIES) + pr_warn("Serverclose failed %d times, giving up\n", MAX_RETRIES); + + if (cifs_file->offload) + queue_work(fileinfo_put_wq, &cifs_file->put); + else + cifsFileInfo_put_final(cifs_file); +} + /** * cifsFileInfo_put - release a reference of file priv data * @@ -507,10 +543,13 @@ void _cifsFileInfo_put(struct cifsFileIn struct cifs_fid fid = {}; struct cifs_pending_open open; bool oplock_break_cancelled; + bool serverclose_offloaded = false;
spin_lock(&tcon->open_file_lock); spin_lock(&cifsi->open_file_lock); spin_lock(&cifs_file->file_info_lock); + + cifs_file->offload = offload; if (--cifs_file->count > 0) { spin_unlock(&cifs_file->file_info_lock); spin_unlock(&cifsi->open_file_lock); @@ -552,13 +591,20 @@ void _cifsFileInfo_put(struct cifsFileIn if (!tcon->need_reconnect && !cifs_file->invalidHandle) { struct TCP_Server_Info *server = tcon->ses->server; unsigned int xid; + int rc = 0;
xid = get_xid(); if (server->ops->close_getattr) - server->ops->close_getattr(xid, tcon, cifs_file); + rc = server->ops->close_getattr(xid, tcon, cifs_file); else if (server->ops->close) - server->ops->close(xid, tcon, &cifs_file->fid); + rc = server->ops->close(xid, tcon, &cifs_file->fid); _free_xid(xid); + + if (rc == -EBUSY || rc == -EAGAIN) { + // Server close failed, hence offloading it as an async op + queue_work(serverclose_wq, &cifs_file->serverclose); + serverclose_offloaded = true; + } }
if (oplock_break_cancelled) @@ -566,10 +612,15 @@ void _cifsFileInfo_put(struct cifsFileIn
cifs_del_pending_open(&open);
- if (offload) - queue_work(fileinfo_put_wq, &cifs_file->put); - else - cifsFileInfo_put_final(cifs_file); + // if serverclose has been offloaded to wq (on failure), it will + // handle offloading put as well. If serverclose not offloaded, + // we need to handle offloading put here. + if (!serverclose_offloaded) { + if (offload) + queue_work(fileinfo_put_wq, &cifs_file->put); + else + cifsFileInfo_put_final(cifs_file); + } }
int cifs_open(struct inode *inode, struct file *file) --- a/fs/smb/client/smb1ops.c +++ b/fs/smb/client/smb1ops.c @@ -750,11 +750,11 @@ cifs_set_fid(struct cifsFileInfo *cfile, cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode); }
-static void +static int cifs_close_file(const unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *fid) { - CIFSSMBClose(xid, tcon, fid->netfid); + return CIFSSMBClose(xid, tcon, fid->netfid); }
static int --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -1392,14 +1392,14 @@ smb2_set_fid(struct cifsFileInfo *cfile, memcpy(cfile->fid.create_guid, fid->create_guid, 16); }
-static void +static int smb2_close_file(const unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *fid) { - SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid); + return SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid); }
-static void +static int smb2_close_getattr(const unsigned int xid, struct cifs_tcon *tcon, struct cifsFileInfo *cfile) { @@ -1410,7 +1410,7 @@ smb2_close_getattr(const unsigned int xi rc = __SMB2_close(xid, tcon, cfile->fid.persistent_fid, cfile->fid.volatile_fid, &file_inf); if (rc) - return; + return rc;
inode = d_inode(cfile->dentry);
@@ -1436,6 +1436,7 @@ smb2_close_getattr(const unsigned int xi
/* End of file and Attributes should not have to be updated on close */ spin_unlock(&inode->i_lock); + return rc; }
static int --- a/fs/smb/client/smb2pdu.c +++ b/fs/smb/client/smb2pdu.c @@ -3452,9 +3452,9 @@ __SMB2_close(const unsigned int xid, str memcpy(&pbuf->network_open_info, &rsp->network_open_info, sizeof(pbuf->network_open_info)); + atomic_dec(&tcon->num_remote_opens); }
- atomic_dec(&tcon->num_remote_opens); close_exit: SMB2_close_free(&rqst); free_rsp_buf(resp_buftype, rsp);