From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 12AA7285404; Wed, 4 Feb 2026 15:01:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770217303; cv=none; b=GhwPSgiRta5dmYWtObS5dcGAeHZN4dmkdcoG3maCDCIO/51tLnZal5bcuWTfpO+k9BAP5/MoNRli505vBF/FlRmtfxOGOyoJogBTEFY4+pTuE7I5sdQ0I+Ai5yq6aLDDs9QisDCO7V99VuWcozdvpe+ni6bJVfCfO7/0t1OoLkQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770217303; c=relaxed/simple; bh=8V8D4l2dzhmg6/GRhObbgTrF+syftXFtWre9W8aFE60=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=s5FxPaWyBmbWgXS8N3mhEzqPn7UGQ4o1lID/JVlgwwcSfYxqln6e7MnAoAPqEVWEO9s9GkMmy+cB2UIiipXgpZKj1HcmA7Y3vXzbGfJGCiHHXJV0/A/E9nsA9yZoazDQ5ngCh2FElURUjRq0zG73nL2Yumc/k5IrbdyjSFJSAoI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Y04N6Jqz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Y04N6Jqz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41269C4CEF7; Wed, 4 Feb 2026 15:01:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1770217302; bh=8V8D4l2dzhmg6/GRhObbgTrF+syftXFtWre9W8aFE60=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y04N6Jqz5BGSpb6M4Pju8/vTnvpDbfNosL9rMzhrOQpsniDVdfkFNst+dqY31JbaL MF1nmOip+7f2XFz3z7tbDDJl10oe6Xg9e5L/ReGlUAY5Mu/cnHEASWmM3VJMth/X6/ tg3cmbAbv1mjjqWD8aII57kxSb3osSySGATTcYoQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ying Hsu , Luiz Augusto von Dentz , Wenshan Lan Subject: [PATCH 5.15 184/206] Bluetooth: Fix hci_suspend_sync crash Date: Wed, 4 Feb 2026 15:40:15 +0100 Message-ID: <20260204143904.847167191@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260204143858.193781818@linuxfoundation.org> References: <20260204143858.193781818@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ying Hsu [ Upstream commit 573ebae162111063eedc6c838a659ba628f66a0f ] If hci_unregister_dev() frees the hci_dev object but hci_suspend_notifier may still be accessing it, it can cause the program to crash. Here's the call trace: <4>[102152.653246] Call Trace: <4>[102152.653254] hci_suspend_sync+0x109/0x301 [bluetooth] <4>[102152.653259] hci_suspend_dev+0x78/0xcd [bluetooth] <4>[102152.653263] hci_suspend_notifier+0x42/0x7a [bluetooth] <4>[102152.653268] notifier_call_chain+0x43/0x6b <4>[102152.653271] __blocking_notifier_call_chain+0x48/0x69 <4>[102152.653273] __pm_notifier_call_chain+0x22/0x39 <4>[102152.653276] pm_suspend+0x287/0x57c <4>[102152.653278] state_store+0xae/0xe5 <4>[102152.653281] kernfs_fop_write+0x109/0x173 <4>[102152.653284] __vfs_write+0x16f/0x1a2 <4>[102152.653287] ? selinux_file_permission+0xca/0x16f <4>[102152.653289] ? security_file_permission+0x36/0x109 <4>[102152.653291] vfs_write+0x114/0x21d <4>[102152.653293] __x64_sys_write+0x7b/0xdb <4>[102152.653296] do_syscall_64+0x59/0x194 <4>[102152.653299] entry_SYSCALL_64_after_hwframe+0x5c/0xc1 This patch holds the reference count of the hci_dev object while processing it in hci_suspend_notifier to avoid potential crash caused by the race condition. Signed-off-by: Ying Hsu Signed-off-by: Luiz Augusto von Dentz [ Adjust context ] Signed-off-by: Wenshan Lan Signed-off-by: Greg Kroah-Hartman --- net/bluetooth/hci_core.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3706,6 +3706,9 @@ static int hci_suspend_notifier(struct n int ret = 0; u8 state = BT_RUNNING; + /* To avoid a potential race with hci_unregister_dev. */ + hci_dev_hold(hdev); + /* If powering down, wait for completion. */ if (mgmt_powering_down(hdev)) { set_bit(SUSPEND_POWERING_DOWN, hdev->suspend_tasks); @@ -3757,6 +3760,7 @@ done: bt_dev_err(hdev, "Suspend notifier action (%lu) failed: %d", action, ret); + hci_dev_put(hdev); return NOTIFY_DONE; }