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 D7BB33769FF for ; Thu, 10 Sep 2026 02:11:16 +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=1789006278; cv=none; b=BnOUEP1FGNtER19eZIvFKqcKEusq2q6WHP1H8RZJ8Vx1FpZ8JMOdzRZLpJKQwsEL27wpMl57B/STAkIErYsGrah2GbPoQMhBflpEvCXICwSVx9hvGLxSd9DuEn2A65QaJfJk7sjwekHovRWnYZu03UxPzRj8AO2XnsiTZwUPgpI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789006278; c=relaxed/simple; bh=IaIk2IQosx/h56aHBvb1dmYfPLpodhU0q+8MTD6kMFc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mCE4HkS4d406wmdRTKcGcdPuKUMEoExTF4qi6/qLIQqdPrNotYCwhf4WYssTW4JLP6L1HMXn35sqos/Nw28Esc69k4R0yWhrGPWPnYeD4UYR4xbxYIjD95DrqbpwQSqATASuOb7AufX1vbnfsMUpvFFXFuDiZAvfBxcR/trgNRA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mCmNhgKI; 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="mCmNhgKI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 227F61F00898; Thu, 10 Sep 2026 02:11:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789006276; bh=AevA6saFGdrtRbN5x/w21/6vccVd43KaktrP2sdWKWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mCmNhgKI2VdTxfKZSm3kL98R8RRMdDs3ytbvmtBpj81ZRjhmQ8gGj+Q4Z+4DIhxj1 wIcaeuZCA5fJ01hB9Wwm5pNqjmbLKtnjbInvY4uIy1d/oiWrsEUUHpTozdLcXl6m2v LG1pu4h23j+f68MIFHfiai/Uez+6x3DAeQff/cd47FNRuI2AFFZOnevAbv14YVvPPP n4d2ep300LxSmCuQf/+hnYYH2YzmweJqTGsAx9xAuGucEpJSqc1T38usVPTbKDZq9h VcBDGEhXaYWD+/zZ5MOBFmETKmIUEeNjdlImXDf/1t9Aio3nHs8dudXKkZpfnuO92d ELn06QmcjBnMA== From: Sasha Levin To: stable@vger.kernel.org Cc: Myeonghun Pak , stable , Ijae Kim , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 6.6.y] usb: storage: realtek_cr: fix use-after-free on disconnect Date: Wed, 9 Sep 2026 22:11:14 -0400 Message-ID: <20260910021114.3989473-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090831-imbecile-crinkle-7c3e@gregkh> References: <2026090831-imbecile-crinkle-7c3e@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: Myeonghun Pak [ Upstream commit 4ffee1aebb0c0ffcda9faffd17834ea9b00d42cc ] realtek_cr_destructor() calls timer_delete() before the chip containing the timer is freed. The timer callback may still be running and can rearm itself, resulting in a use-after-free. Use timer_shutdown_sync() to wait for the callback and prevent further rearming. Do this unconditionally because ss_en may be changed after the timer is armed. Move timer_setup() into init_realtek_cr() so the timer is initialized before any failure path can invoke the destructor. Found by static analysis. Fixes: e931830bb877 ("Realtek cr: Add autosuspend function.") Cc: stable Co-developed-by: Ijae Kim Signed-off-by: Ijae Kim Signed-off-by: Myeonghun Pak Link: https://patch.msgid.link/20260727123414.44700-1-mhun512@gmail.com Signed-off-by: Greg Kroah-Hartman [ adapted the timer_delete() removal to the branch’s del_timer() spelling. ] Signed-off-by: Sasha Levin --- drivers/usb/storage/realtek_cr.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/usb/storage/realtek_cr.c b/drivers/usb/storage/realtek_cr.c index a026c6cb6e684..de82d8260d729 100644 --- a/drivers/usb/storage/realtek_cr.c +++ b/drivers/usb/storage/realtek_cr.c @@ -915,7 +915,6 @@ static int realtek_cr_autosuspend_setup(struct us_data *us) us->proto_handler = rts51x_invoke_transport; chip->timer_expires = 0; - timer_setup(&chip->rts51x_suspend_timer, rts51x_suspend_timer_fn, 0); fw5895_init(us); /* enable autosuspend function of the usb device */ @@ -933,10 +932,7 @@ static void realtek_cr_destructor(void *extra) return; #ifdef CONFIG_REALTEK_AUTOPM - if (ss_en) { - del_timer(&chip->rts51x_suspend_timer); - chip->timer_expires = 0; - } + timer_shutdown_sync(&chip->rts51x_suspend_timer); #endif kfree(chip->status); } @@ -981,6 +977,9 @@ static int init_realtek_cr(struct us_data *us) us->extra = chip; us->extra_destructor = realtek_cr_destructor; +#ifdef CONFIG_REALTEK_AUTOPM + timer_setup(&chip->rts51x_suspend_timer, rts51x_suspend_timer_fn, 0); +#endif us->max_lun = chip->max_lun = rts51x_get_max_lun(us); chip->us = us; -- 2.53.0