The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x d3ca9f7aeba793d74361d88a8800b2f205c9236b # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '16781022287459@kroah.com' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

d3ca9f7aeba7 ("ksmbd: fix possible memory leak in smb2_lock()") edf5f0548fbb ("ksmbd: replace usage of found with dedicated list iterator variable") cb4517201b8a ("ksmbd: remove smb2_buf_length in smb2_hdr") 341b16014bf8 ("ksmdb: use cmd helper variable in smb2_get_ksmbd_tcon()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d3ca9f7aeba793d74361d88a8800b2f205c9236b Mon Sep 17 00:00:00 2001 From: Hangyu Hua hbh25y@gmail.com Date: Fri, 17 Feb 2023 22:29:34 +0900 Subject: [PATCH] ksmbd: fix possible memory leak in smb2_lock()

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") Cc: stable@vger.kernel.org Signed-off-by: Hangyu Hua hbh25y@gmail.com Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index a225727d4bc1..33cfc8d80c2c 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -6626,7 +6626,7 @@ 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", @@ -6648,7 +6648,9 @@ 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); @@ -6667,18 +6669,12 @@ 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; @@ -7043,6 +7039,14 @@ int smb2_lock(struct ksmbd_work *work)

ksmbd_vfs_posix_lock_wait(flock);

+ spin_lock(&work->conn->request_lock); + spin_lock(&fp->f_lock); + list_del(&work->fp_entry); + work->cancel_fn = NULL; + kfree(argv); + spin_unlock(&fp->f_lock); + spin_unlock(&work->conn->request_lock); + if (work->state != KSMBD_WORK_ACTIVE) { list_del(&smb_lock->llist); spin_lock(&work->conn->llist_lock); @@ -7051,9 +7055,6 @@ int smb2_lock(struct ksmbd_work *work) locks_free_lock(flock);

if (work->state == KSMBD_WORK_CANCELLED) { - spin_lock(&fp->f_lock); - list_del(&work->fp_entry); - spin_unlock(&fp->f_lock); rsp->hdr.Status = STATUS_CANCELLED; kfree(smb_lock); @@ -7075,9 +7076,6 @@ int smb2_lock(struct ksmbd_work *work) list_del(&smb_lock->clist); spin_unlock(&work->conn->llist_lock);

- spin_lock(&fp->f_lock); - list_del(&work->fp_entry); - spin_unlock(&fp->f_lock); 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..0ae5dd0829e9 100644 --- a/fs/ksmbd/vfs_cache.c +++ b/fs/ksmbd/vfs_cache.c @@ -364,12 +364,11 @@ static void __put_fd_final(struct ksmbd_work *work, struct ksmbd_file *fp)

static void set_close_state_blocked_works(struct ksmbd_file *fp) { - struct ksmbd_work *cancel_work, *ctmp; + struct ksmbd_work *cancel_work;

spin_lock(&fp->f_lock); - list_for_each_entry_safe(cancel_work, ctmp, &fp->blocked_works, + list_for_each_entry(cancel_work, &fp->blocked_works, fp_entry) { - list_del(&cancel_work->fp_entry); cancel_work->state = KSMBD_WORK_CLOSED; cancel_work->cancel_fn(cancel_work->cancel_argv); }