RE: [PATCH 5.2 02/45] smb3: fix unmount hang in open_shroot
-Original Message- From: Sasha Levin Sent: Tuesday, October 1, 2019 3:49 PM > On Tue, Oct 01, 2019 at 08:41:43PM +, Pavel Shilovskiy wrote: > >Hi Greg, > > > >Are you going to apply this patch to the 5.3.y stable kernel? The patch is > >applicable there too. > > I will, yes. Thanks! Best regards, Pavel Shilovsky
Re: [PATCH 5.2 02/45] smb3: fix unmount hang in open_shroot
On Tue, Oct 01, 2019 at 08:41:43PM +, Pavel Shilovskiy wrote: Hi Greg, Are you going to apply this patch to the 5.3.y stable kernel? The patch is applicable there too. I will, yes. -- Thanks, Sasha
RE: [PATCH 5.2 02/45] smb3: fix unmount hang in open_shroot
Hi Greg,
Are you going to apply this patch to the 5.3.y stable kernel? The patch is
applicable there too.
Best regards,
Pavel Shilovsky
-Original Message-
From: Greg Kroah-Hartman
Sent: Sunday, September 29, 2019 6:56 AM
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman ; sta...@vger.kernel.org;
kbuild test robot ; Dan Carpenter ;
Pavel Shilovskiy ; Steven French
; Aurelien Aptel ; Sasha Levin
Subject: [PATCH 5.2 02/45] smb3: fix unmount hang in open_shroot
From: Steve French
[ Upstream commit 96d9f7ed00b86104bf03adeffc8980897e9694ab ]
An earlier patch "CIFS: fix deadlock in cached root handling"
did not completely address the deadlock in open_shroot. This patch addresses
the deadlock.
In testing the recent patch:
smb3: improve handling of share deleted (and share recreated) we were able to
reproduce the open_shroot deadlock to one of the target servers in unmount in a
delete share scenario.
Fixes: 7e5a70ad88b1e ("CIFS: fix deadlock in cached root handling")
This is version 2 of this patch. An earlier version of this patch "smb3: fix
unmount hang in open_shroot" had a problem found by Dan.
Reported-by: kbuild test robot
Reported-by: Dan Carpenter
Suggested-by: Pavel Shilovsky
Reviewed-by: Pavel Shilovsky
Signed-off-by: Steve French
CC: Aurelien Aptel
CC: Stable
Signed-off-by: Sasha Levin
---
fs/cifs/smb2ops.c | 21 +++--
1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index
42de31d206169..8ae8ef526b4a5 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -656,6 +656,15 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
return 0;
}
+ /*
+* We do not hold the lock for the open because in case
+* SMB2_open needs to reconnect, it will end up calling
+* cifs_mark_open_files_invalid() which takes the lock again
+* thus causing a deadlock
+*/
+
+ mutex_unlock(>crfid.fid_mutex);
+
if (smb3_encryption_required(tcon))
flags |= CIFS_TRANSFORM_REQ;
@@ -677,7 +686,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
rc = SMB2_open_init(tcon, [0], , , _path);
if (rc)
- goto oshr_exit;
+ goto oshr_free;
smb2_set_next_command(tcon, [0]);
memset(_iov, 0, sizeof(qi_iov));
@@ -690,18 +699,10 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
sizeof(struct smb2_file_all_info) +
PATH_MAX * 2, 0, NULL);
if (rc)
- goto oshr_exit;
+ goto oshr_free;
smb2_set_related([1]);
- /*
-* We do not hold the lock for the open because in case
-* SMB2_open needs to reconnect, it will end up calling
-* cifs_mark_open_files_invalid() which takes the lock again
-* thus causing a deadlock
-*/
-
- mutex_unlock(>crfid.fid_mutex);
rc = compound_send_recv(xid, ses, flags, 2, rqst,
resp_buftype, rsp_iov);
mutex_lock(>crfid.fid_mutex);
--
2.20.1
[PATCH 5.2 02/45] smb3: fix unmount hang in open_shroot
From: Steve French
[ Upstream commit 96d9f7ed00b86104bf03adeffc8980897e9694ab ]
An earlier patch "CIFS: fix deadlock in cached root handling"
did not completely address the deadlock in open_shroot. This
patch addresses the deadlock.
In testing the recent patch:
smb3: improve handling of share deleted (and share recreated)
we were able to reproduce the open_shroot deadlock to one
of the target servers in unmount in a delete share scenario.
Fixes: 7e5a70ad88b1e ("CIFS: fix deadlock in cached root handling")
This is version 2 of this patch. An earlier version of this
patch "smb3: fix unmount hang in open_shroot" had a problem
found by Dan.
Reported-by: kbuild test robot
Reported-by: Dan Carpenter
Suggested-by: Pavel Shilovsky
Reviewed-by: Pavel Shilovsky
Signed-off-by: Steve French
CC: Aurelien Aptel
CC: Stable
Signed-off-by: Sasha Levin
---
fs/cifs/smb2ops.c | 21 +++--
1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 42de31d206169..8ae8ef526b4a5 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -656,6 +656,15 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
return 0;
}
+ /*
+* We do not hold the lock for the open because in case
+* SMB2_open needs to reconnect, it will end up calling
+* cifs_mark_open_files_invalid() which takes the lock again
+* thus causing a deadlock
+*/
+
+ mutex_unlock(>crfid.fid_mutex);
+
if (smb3_encryption_required(tcon))
flags |= CIFS_TRANSFORM_REQ;
@@ -677,7 +686,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
rc = SMB2_open_init(tcon, [0], , , _path);
if (rc)
- goto oshr_exit;
+ goto oshr_free;
smb2_set_next_command(tcon, [0]);
memset(_iov, 0, sizeof(qi_iov));
@@ -690,18 +699,10 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid)
sizeof(struct smb2_file_all_info) +
PATH_MAX * 2, 0, NULL);
if (rc)
- goto oshr_exit;
+ goto oshr_free;
smb2_set_related([1]);
- /*
-* We do not hold the lock for the open because in case
-* SMB2_open needs to reconnect, it will end up calling
-* cifs_mark_open_files_invalid() which takes the lock again
-* thus causing a deadlock
-*/
-
- mutex_unlock(>crfid.fid_mutex);
rc = compound_send_recv(xid, ses, flags, 2, rqst,
resp_buftype, rsp_iov);
mutex_lock(>crfid.fid_mutex);
--
2.20.1
