argv needs to be free when setup_async_work fails or when the current
process is woken up.
Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Hangyu Hua <[email protected]>
---
v2: avoid NULL pointer dereference in set_close_state_blocked_works()
v3: avoid race condition between smb2_lock() and smb2_cancel()
fs/ksmbd/smb2pdu.c | 23 ++++++++++++++---------
fs/ksmbd/vfs_cache.c | 2 ++
2 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index d681f91947d9..f4079518eaf6 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -6644,7 +6644,7 @@ int smb2_cancel(struct ksmbd_work *work)
struct ksmbd_conn *conn = work->conn;
struct smb2_hdr *hdr = smb2_get_msg(work->request_buf);
struct smb2_hdr *chdr;
- struct ksmbd_work *cancel_work = NULL, *iter;
+ struct ksmbd_work *iter;
struct list_head *command_list;
ksmbd_debug(SMB, "smb2 cancel called on mid %llu, async flags 0x%x\n",
@@ -6666,7 +6666,9 @@ int smb2_cancel(struct ksmbd_work *work)
"smb2 with AsyncId %llu cancelled command = 0x%x\n",
le64_to_cpu(hdr->Id.AsyncId),
le16_to_cpu(chdr->Command));
- cancel_work = iter;
+ iter->state = KSMBD_WORK_CANCELLED;
+ if (iter->cancel_fn)
+ iter->cancel_fn(iter->cancel_argv);
break;
}
spin_unlock(&conn->request_lock);
@@ -6685,18 +6687,12 @@ int smb2_cancel(struct ksmbd_work *work)
"smb2 with mid %llu cancelled command = 0x%x\n",
le64_to_cpu(hdr->MessageId),
le16_to_cpu(chdr->Command));
- cancel_work = iter;
+ iter->state = KSMBD_WORK_CANCELLED;
break;
}
spin_unlock(&conn->request_lock);
}
- if (cancel_work) {
- cancel_work->state = KSMBD_WORK_CANCELLED;
- if (cancel_work->cancel_fn)
- cancel_work->cancel_fn(cancel_work->cancel_argv);
- }
-
/* For SMB2_CANCEL command itself send no response*/
work->send_no_response = 1;
return 0;
@@ -7050,6 +7046,7 @@ int smb2_lock(struct ksmbd_work *work)
smb2_remove_blocked_lock,
argv);
if (rc) {
+ kfree(argv);
err = -ENOMEM;
goto out;
}
@@ -7061,6 +7058,10 @@ int smb2_lock(struct ksmbd_work *work)
ksmbd_vfs_posix_lock_wait(flock);
+ spin_lock(&work->conn->request_lock);
+ list_del_init(&work->async_request_entry);
+ spin_unlock(&work->conn->request_lock);
+
if (work->state != KSMBD_WORK_ACTIVE) {
list_del(&smb_lock->llist);
spin_lock(&work->conn->llist_lock);
@@ -7072,6 +7073,8 @@ int smb2_lock(struct ksmbd_work *work)
spin_lock(&fp->f_lock);
list_del(&work->fp_entry);
spin_unlock(&fp->f_lock);
+ work->cancel_fn = NULL;
+ kfree(argv);
rsp->hdr.Status =
STATUS_CANCELLED;
kfree(smb_lock);
@@ -7096,6 +7099,8 @@ int smb2_lock(struct ksmbd_work *work)
spin_lock(&fp->f_lock);
list_del(&work->fp_entry);
spin_unlock(&fp->f_lock);
+ work->cancel_fn = NULL;
+ kfree(argv);
goto retry;
} else if (!rc) {
spin_lock(&work->conn->llist_lock);
diff --git a/fs/ksmbd/vfs_cache.c b/fs/ksmbd/vfs_cache.c
index da9163b00350..761a8aa540ce 100644
--- a/fs/ksmbd/vfs_cache.c
+++ b/fs/ksmbd/vfs_cache.c
@@ -372,6 +372,8 @@ static void set_close_state_blocked_works(struct ksmbd_file *fp)
list_del(&cancel_work->fp_entry);
cancel_work->state = KSMBD_WORK_CLOSED;
cancel_work->cancel_fn(cancel_work->cancel_argv);
+ cancel_work->cancel_fn = NULL;
+ kfree(cancel_work->cancel_argv);
}
spin_unlock(&fp->f_lock);
}
--
2.34.1
2023-02-07 17:07 GMT+09:00, Hangyu Hua <[email protected]>:
> argv needs to be free when setup_async_work fails or when the current
> process is woken up.
>
> Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
> Signed-off-by: Hangyu Hua <[email protected]>
> ---
>
> v2: avoid NULL pointer dereference in set_close_state_blocked_works()
> v3: avoid race condition between smb2_lock() and smb2_cancel()
>
> fs/ksmbd/smb2pdu.c | 23 ++++++++++++++---------
> fs/ksmbd/vfs_cache.c | 2 ++
> 2 files changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index d681f91947d9..f4079518eaf6 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -6644,7 +6644,7 @@ int smb2_cancel(struct ksmbd_work *work)
> struct ksmbd_conn *conn = work->conn;
> struct smb2_hdr *hdr = smb2_get_msg(work->request_buf);
> struct smb2_hdr *chdr;
> - struct ksmbd_work *cancel_work = NULL, *iter;
> + struct ksmbd_work *iter;
> struct list_head *command_list;
>
> ksmbd_debug(SMB, "smb2 cancel called on mid %llu, async flags 0x%x\n",
> @@ -6666,7 +6666,9 @@ int smb2_cancel(struct ksmbd_work *work)
> "smb2 with AsyncId %llu cancelled command = 0x%x\n",
> le64_to_cpu(hdr->Id.AsyncId),
> le16_to_cpu(chdr->Command));
> - cancel_work = iter;
> + iter->state = KSMBD_WORK_CANCELLED;
> + if (iter->cancel_fn)
> + iter->cancel_fn(iter->cancel_argv);
> break;
> }
> spin_unlock(&conn->request_lock);
> @@ -6685,18 +6687,12 @@ int smb2_cancel(struct ksmbd_work *work)
> "smb2 with mid %llu cancelled command = 0x%x\n",
> le64_to_cpu(hdr->MessageId),
> le16_to_cpu(chdr->Command));
> - cancel_work = iter;
> + iter->state = KSMBD_WORK_CANCELLED;
> break;
> }
> spin_unlock(&conn->request_lock);
> }
>
> - if (cancel_work) {
> - cancel_work->state = KSMBD_WORK_CANCELLED;
> - if (cancel_work->cancel_fn)
> - cancel_work->cancel_fn(cancel_work->cancel_argv);
> - }
> -
> /* For SMB2_CANCEL command itself send no response*/
> work->send_no_response = 1;
> return 0;
> @@ -7050,6 +7046,7 @@ int smb2_lock(struct ksmbd_work *work)
> smb2_remove_blocked_lock,
> argv);
> if (rc) {
> + kfree(argv);
> err = -ENOMEM;
> goto out;
> }
> @@ -7061,6 +7058,10 @@ int smb2_lock(struct ksmbd_work *work)
>
> ksmbd_vfs_posix_lock_wait(flock);
>
> + spin_lock(&work->conn->request_lock);
> + list_del_init(&work->async_request_entry);
It is called again in ksmbd_conn_try_dequeue_request().
> + spin_unlock(&work->conn->request_lock);
> +