From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E43D43C5DDB for ; Mon, 20 Jul 2026 13:51:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784555462; cv=none; b=a+iugpbFjBQfSrKvq4suli7oiYI9VASyfGFWMS12b24VnB0u8yXsVDsdAb2l7S3B4IEvaflDctMOFksyKFIT1GaQrKBG793xYTbKyoykd2pDqZuGcXS6M2nnXSW9XA3usUYbiHrzaxY0PWe0CnaHFzHcLWYwhSKXZWW7cbQGblg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784555462; c=relaxed/simple; bh=+iD8aoMh/OUDC//lKDNd7AYT8jnqE6O6FJXnryZj7K8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=m5qOSxWDwXdlPo4jvEJRBTWUJagLi+pu9ylQx87lxRXP/PKn0p0CrTsEPt8PclMJV+SPchPUBwbtmBGst39duhkx+/S4UTXv/uMFsIwShrOl8d8DE84LumZtEbzUCr46Fl+4SP4fV8W9WYLJiqlC/FrJq6+alg9oGt2F5Rq7IqA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cy7NA0SK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cy7NA0SK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1CBC1F000E9; Mon, 20 Jul 2026 13:50:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784555460; bh=xJW8pkk4DYLB3VTdn/X+xXw5mshIyvn/idcV1dggv6c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cy7NA0SK9Yz/FjfsentdSHpvtc049TLyHTfQ+fGI4BqPtwfuAgwD0WCKkN0OAdiY2 IojCh0UJCBK5b61aD41dgq3U/IAJ+MYJpvxAaI4H7E7YN4SsJZUkKovz7Fvqh6lwwx ug6yOwHAffTNv6ZEAL/GQPRUtmlocJBfqQ+OrxO7OeLddkpTRLdNhkS76ShXG4W3cj BrM+DcpFgkD4pfSljiIiJ/NotuaaH0ks9AsOMi5hUGSEK59g6MptfBD4A5XCXuAGo8 AS8F0eP3usOPn0SPVAF2X9WIKV7CKl+UOUjc9bLnCnXLTbe3odHBmV29ODH8D3Gz81 FxOMktJIqb/9Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Tyler Baker , stable , Loic Poulain , Dmitry Baryshkov , Srinivas Kandagatla , Peter Chen , =?UTF-8?q?Micha=C5=82=20Nazarewicz?= , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 6.1.y] usb: gadget: f_fs: initialize reset_work at allocation time Date: Mon, 20 Jul 2026 09:50:57 -0400 Message-ID: <20260720135057.1305612-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026071456-vertigo-moonstone-5301@gregkh> References: <2026071456-vertigo-moonstone-5301@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Tyler Baker [ Upstream commit 3137b243c93982fe3460335e12f9247739766e10 ] ffs_fs_kill_sb() unconditionally calls cancel_work_sync() on ffs->reset_work when a functionfs instance is unmounted: ffs_data_reset(ffs); cancel_work_sync(&ffs->reset_work); However ffs->reset_work is only ever initialized via INIT_WORK() in ffs_func_set_alt() and ffs_func_disable(), and only on the FFS_DEACTIVATED path. That state is reached solely by ffs_data_closed() when the instance is mounted with the "no_disconnect" option, so for the common case (no "no_disconnect", or mounted and unmounted without ever being deactivated) reset_work is never initialized. ffs_data_new() allocates the ffs_data with kzalloc_obj() and does not initialize reset_work, and ffs_data_reset()/ffs_data_clear() do not touch it either, so reset_work.func is left NULL. cancel_work_sync() on such a work then trips the WARN_ON(!work->func) guard in __flush_work(): WARNING: kernel/workqueue.c:4301 at __flush_work+0x330/0x360, CPU#3: umount Call trace: __flush_work cancel_work_sync ffs_fs_kill_sb [usb_f_fs] deactivate_locked_super deactivate_super cleanup_mnt __cleanup_mnt task_work_run exit_to_user_mode_loop el0_svc On older kernels cancel_work_sync() on a zero-initialized work struct was a silent no-op, which hid the missing initialization. Initialize reset_work once in ffs_data_new() so it is always valid for the lifetime of the ffs_data, and drop the now-redundant INIT_WORK() calls from the two deactivation paths. Fixes: 18d6b32fca38 ("usb: gadget: f_fs: add "no_disconnect" mode") Cc: stable Signed-off-by: Tyler Baker Cc: Loic Poulain Cc: Dmitry Baryshkov Cc: Srinivas Kandagatla Tested-by: Loic Poulain Reviewed-by: Peter Chen Acked-by: Michał Nazarewicz Link: https://patch.msgid.link/20260609193635.2284430-1-tyler.baker@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman [ dropped the ffs_func_disable hunk since 6.6 predates the disable-body split and routes disable through ffs_func_set_alt, so removing the single lazy INIT_WORK there covers both paths ] Signed-off-by: Sasha Levin --- drivers/usb/gadget/function/f_fs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index e88da01620b072..3cba6ff806dc0e 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -255,6 +255,7 @@ static int ffs_acquire_dev(const char *dev_name, struct ffs_data *ffs_data); static void ffs_release_dev(struct ffs_dev *ffs_dev); static int ffs_ready(struct ffs_data *ffs); static void ffs_closed(struct ffs_data *ffs); +static void ffs_reset_work(struct work_struct *work); /* Misc helper functions ****************************************************/ @@ -1786,6 +1787,7 @@ static struct ffs_data *ffs_data_new(const char *dev_name) init_waitqueue_head(&ffs->ev.waitq); init_waitqueue_head(&ffs->wait); init_completion(&ffs->ep0req_completion); + INIT_WORK(&ffs->reset_work, ffs_reset_work); /* XXX REVISIT need to update it in some places, or do we? */ ffs->ev.can_stall = 1; @@ -3342,7 +3344,6 @@ static int ffs_func_set_alt(struct usb_function *f, if (ffs->state == FFS_DEACTIVATED) { ffs->state = FFS_CLOSING; - INIT_WORK(&ffs->reset_work, ffs_reset_work); schedule_work(&ffs->reset_work); return -ENODEV; } -- 2.53.0