From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794064851; b=2KdZ8fWR44XQXJjSJr2HDV6yPgl6Wjp0GEpEq9xUYfS4j1nahbZbRltxiqEek99+D3uJ 7dHnPunaUTaJogEZ7c/O2KQnWrBcbLYw9IQIKoyOp813/qBEjveT0XsM43M55uKYawtaw pvQzUQyITLY6P4XyC5eKlEgFDLXDxLkvEbdlGBvAx8lzv0RYOKvzTCn0vgpsAJ13r3R8t p6ep5W/YA88A8MQ7jednM1to2cQEqgH1IB/+3rmTUmkxW8KlNxXbIKlWrqoXldzuA4ch4 Zu6k2uyKmnjckc1jJqLUwUDh3uCWZL7DWWg/Nu0HywLN03MCyaf1D+WswPVz2jOVUNQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794064851; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=BhYTQNSBmR/Him6ZZcj78vzrrMWs2a+CBNj74aZoJEU=; b=yFuONkPDdgOxklL8BldpRNJPsHoyTumCHRYyk2AH+ix1ReOIoDNHo7GqIfrifzYE9A6a hWFAGyBQFBWGFm3ZNTV1xdE/PDPqMudpovWyd/GbrMD6MRh54O+G/0DS6reIodXd7udwm g5qNejKUpdplJnwc3D3oxdmytWseU7nYOF701wtP7jp5CaRqQIpwEwwmjCZ5jCMCiF0AA /+yDZA21QFJvKDooBzzdX6k646W2Uc9sH9WRJGKIuV+/lHCS8fduXRrFUOFQbk6KYvAfw FaIjV9trV+AJOvzMY/DzuCzNpM+ySs8M5Zey27c5Hc9ihlBCeY/6ca1FCwxfk2fUN7A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=yEhY6BsC; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DE22606B8B2; Sat, 7 Nov 2026 15:20:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=yEhY6BsC Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC0181F0089F; Sat, 7 Nov 2026 15:20:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794064851; bh=BhYTQNSBmR/Him6ZZcj78vzrrMWs2a+CBNj74aZoJEU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yEhY6BsCLyOuyv1qkodraDlDJNuV0cijoMGHUX35V7tiSBYEmoGF5P7HQdvjSLs9Q roxk1YDtZicY1WApcgOBAEYqDs+/uMHcpp+GxSm6UwJCS6capYkWZO6PvR/bD+wwb3 EO9Xx0yuGSMZ7oMfAOskWbdDO3iF48Jk/mNgsivc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bui Viet Dung , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 7.3 0774/1257] Bluetooth: hci_debugfs: Pin module for debugfs file operations Date: Sat, 7 Nov 2026 08:51:10 -0500 Message-ID: <20261107135000.679509248@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bui Viet Dung [ Upstream commit 2a3e2287877b1ee40ffb80b7d769b633866533f3 ] An open debugfs file retains its file_operations pointer in the debugfs proxy state. However, the file_operations defined in hci_debugfs.c (use_debug_keys_fops, sc_only_mode_fops, ssp_debug_mode_fops, force_bredr_smp_fops, force_static_address_fops, force_no_mitm_fops, dut_mode_fops, vendor_diag_fops, and the DEFINE_QUIRK_ATTRIBUTE macro) have no .owner set to THIS_MODULE. As a result, full_proxy_open_regular() calls fops_get() which succeeds without taking a reference to the bluetooth module. When a userspace process opens any of these debugfs files, a subsequent controller removal and module unload (rmmod bluetooth) can succeed while the file descriptor remains open. When the userspace process subsequently closes the descriptor, full_proxy_release() accesses the already unmapped file_operations structure, triggering a kernel oops in full_proxy_release(): BUG: unable to handle page fault for address: fffffbfff8056f03 #PF: supervisor read access in kernel mode Oops: 0000 [#1] SMP KASAN NOPTI RIP: 0010:full_proxy_release+0x8e/0x140 Call Trace: __fput+0x39f/0xa60 fput_close_sync+0xff/0x200 __x64_sys_close+0x8c/0xf0 do_syscall_64+0x115/0x6a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f The issue was discovered via manual code audit of net/bluetooth/hci_debugfs.c and verified on a Linux 7.3-rc6 test VM with CONFIG_BT=m. Set .owner = THIS_MODULE on all debugfs file_operations tables in hci_debugfs.c so that debugfs keeps the module loaded until close has finished. Fixes: 0886aea6acd2 ("Bluetooth: Expose debug keys usage setting via debugfs") Cc: stable@vger.kernel.org Signed-off-by: Bui Viet Dung Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/hci_debugfs.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/bluetooth/hci_debugfs.c b/net/bluetooth/hci_debugfs.c index 2559fb6324d63..cd5ef398f2382 100644 --- a/net/bluetooth/hci_debugfs.c +++ b/net/bluetooth/hci_debugfs.c @@ -65,6 +65,7 @@ static ssize_t __name ## _write(struct file *file, \ } \ \ static const struct file_operations __name ## _fops = { \ + .owner = THIS_MODULE, \ .open = simple_open, \ .read = __name ## _read, \ .write = __name ## _write, \ @@ -283,6 +284,7 @@ static ssize_t use_debug_keys_read(struct file *file, char __user *user_buf, } static const struct file_operations use_debug_keys_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = use_debug_keys_read, .llseek = default_llseek, @@ -301,6 +303,7 @@ static ssize_t sc_only_mode_read(struct file *file, char __user *user_buf, } static const struct file_operations sc_only_mode_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = sc_only_mode_read, .llseek = default_llseek, @@ -437,6 +440,7 @@ static ssize_t ssp_debug_mode_read(struct file *file, char __user *user_buf, } static const struct file_operations ssp_debug_mode_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = ssp_debug_mode_read, .llseek = default_llseek, @@ -529,6 +533,7 @@ static ssize_t force_bredr_smp_write(struct file *file, } static const struct file_operations force_bredr_smp_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = force_bredr_smp_read, .write = force_bredr_smp_write, @@ -778,6 +783,7 @@ static ssize_t force_static_address_write(struct file *file, } static const struct file_operations force_static_address_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = force_static_address_read, .write = force_static_address_write, @@ -1177,6 +1183,7 @@ static ssize_t force_no_mitm_write(struct file *file, } static const struct file_operations force_no_mitm_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = force_no_mitm_read, .write = force_no_mitm_write, @@ -1315,6 +1322,7 @@ static ssize_t dut_mode_write(struct file *file, const char __user *user_buf, } static const struct file_operations dut_mode_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = dut_mode_read, .write = dut_mode_write, @@ -1371,6 +1379,7 @@ static ssize_t vendor_diag_write(struct file *file, const char __user *user_buf, } static const struct file_operations vendor_diag_fops = { + .owner = THIS_MODULE, .open = simple_open, .read = vendor_diag_read, .write = vendor_diag_write, -- 2.53.0