Merge "diag: Fix race condition while accessing mdlog session info" (1743983a) · Commits · e / devices / android_kernel_sony_msm8998

drivers/char/diag/diagchar.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -418,6 +418,7 @@ struct diag_md_session_t {
		struct diag_mask_info *msg_mask;
		struct diag_mask_info *log_mask;
		struct diag_mask_info *event_mask;
		struct thread_info *md_client_thread_info;
		struct task_struct *task;
		};

drivers/char/diag/diagchar_core.c

+16 −4

Original line number	Diff line number	Diff line
		@@ -1237,11 +1237,10 @@ int diag_md_session_create(int mode, int peripheral_mask, int proc)
		mutex_unlock(&driver->md_session_lock);
		return -ENOMEM;
		}

		new_session->peripheral_mask = 0;
		new_session->pid = current->tgid;
		new_session->task = current;

		new_session->md_client_thread_info = current_thread_info();
		new_session->log_mask = kzalloc(sizeof(struct diag_mask_info),
		GFP_KERNEL);
		if (!new_session->log_mask) {
		@@ -1359,7 +1358,6 @@ static void diag_md_session_close(struct diag_md_session_t *session_info)
		struct diag_md_session_t *diag_md_session_get_pid(int pid)
		{
		int i;

		for (i = 0; i < NUM_MD_SESSIONS; i++) {
		if (driver->md_session_map[i] &&
		driver->md_session_map[i]->pid == pid)
		@@ -1475,7 +1473,10 @@ static int diag_md_session_check(int curr_mode, int req_mode,
		* If this session owns all the requested peripherals, then
		* call function to switch the modes/masks for the md_session
		*/
		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);

		if (!session_info) {
		*change_mode = 1;
		return 0;
		@@ -1504,7 +1505,9 @@ static int diag_md_session_check(int curr_mode, int req_mode,
		* owned by this md session
		*/
		change_mask = driver->md_session_mask & param->peripheral_mask;
		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);

		if (session_info) {
		if ((session_info->peripheral_mask & change_mask)
		@@ -1892,8 +1895,9 @@ static int diag_ioctl_hdlc_toggle(unsigned long ioarg)
		{
		uint8_t hdlc_support;
		struct diag_md_session_t *session_info = NULL;

		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);
		if (copy_from_user(&hdlc_support, (void __user *)ioarg,
		sizeof(uint8_t)))
		return -EFAULT;
		@@ -2603,7 +2607,9 @@ static int diag_user_process_raw_data(const char __user *buf, int len)
		} else {
		wait_event_interruptible(driver->wait_q,
		(driver->in_busy_pktdata == 0));
		mutex_lock(&driver->md_session_lock);
		info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);
		ret = diag_process_apps_pkt(user_space_data, len, info);
		if (ret == 1)
		diag_send_error_rsp((void *)(user_space_data), len,
		@@ -2671,7 +2677,9 @@ static int diag_user_process_userspace_data(const char __user *buf, int len)

		/* send masks to local processor now */
		if (!remote_proc) {
		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);
		if (!session_info) {
		pr_err("diag:In %s request came from invalid md session pid:%d",
		__func__, current->tgid);
		@@ -2832,7 +2840,9 @@ static ssize_t diagchar_read(struct file file, char __user buf, size_t count,
		COPY_USER_SPACE_OR_EXIT(buf, data_type, sizeof(int));
		/* place holder for number of data field */
		ret += sizeof(int);
		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);
		exit_stat = diag_md_copy_to_user(buf, &ret, count,
		session_info);
		goto exit;
		@@ -2846,7 +2856,9 @@ static ssize_t diagchar_read(struct file file, char __user buf, size_t count,
		data_type = driver->data_ready[index] & HDLC_SUPPORT_TYPE;
		driver->data_ready[index] ^= HDLC_SUPPORT_TYPE;
		COPY_USER_SPACE_OR_EXIT(buf, data_type, sizeof(int));
		mutex_lock(&driver->md_session_lock);
		session_info = diag_md_session_get_pid(current->tgid);
		mutex_unlock(&driver->md_session_lock);
		if (session_info)
		COPY_USER_SPACE_OR_EXIT(buf+4,
		session_info->hdlc_disabled,

drivers/char/diag/diagfwd_cntl.c

+4 −2

Original line number	Diff line number	Diff line
		/* Copyright (c) 2011-2016, The Linux Foundation. All rights reserved.
		/* Copyright (c) 2011-2017, The Linux Foundation. All rights reserved.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 and
		@@ -124,7 +124,9 @@ void diag_notify_md_client(uint8_t peripheral, int data)
		info.si_signo = SIGCONT;
		if (driver->md_session_map[peripheral] &&
		driver->md_session_map[peripheral]->task) {
		if (driver->md_session_map[peripheral]->pid ==
		if (driver->md_session_map[peripheral]->
		md_client_thread_info->task != NULL
		&& driver->md_session_map[peripheral]->pid ==
		driver->md_session_map[peripheral]->task->tgid) {
		DIAG_LOG(DIAG_DEBUG_PERIPHERALS,
		"md_session %d pid = %d, md_session %d task tgid = %d\n",