From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Guy Briggs Subject: [RFC PATCH ghak32 V2 13/13] debug audit: read container ID of a process Date: Fri, 16 Mar 2018 05:00:40 -0400 Message-ID: <1081821010c124fe4e35984ec3dac1654453bb7c.1521179281.git.rgb@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: In-Reply-To: References: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-audit-bounces@redhat.com Errors-To: linux-audit-bounces@redhat.com To: cgroups@vger.kernel.org, containers@lists.linux-foundation.org, linux-api@vger.kernel.org, Linux-Audit Mailing List , linux-fsdevel@vger.kernel.org, LKML , netdev@vger.kernel.org Cc: ebiederm@xmission.com, luto@kernel.org, jlayton@redhat.com, carlos@redhat.com, Richard Guy Briggs , dhowells@redhat.com, viro@zeniv.linux.org.uk, simo@redhat.com, eparis@parisplace.org, serge@hallyn.com List-Id: linux-api@vger.kernel.org Add support for reading the container ID from the proc filesystem. This is a read from the proc entry of the form /proc/PID/containerid where PID is the process ID of the task whose container ID is sought. The read expects up to a u64 value (unset: 18446744073709551615). Signed-off-by: Richard Guy Briggs --- fs/proc/base.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 6ce4fbe..f66d1e2 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1300,6 +1300,21 @@ static ssize_t proc_sessionid_read(struct file * file, char __user * buf, .llseek = generic_file_llseek, }; +static ssize_t proc_containerid_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct inode *inode = file_inode(file); + struct task_struct *task = get_proc_task(inode); + ssize_t length; + char tmpbuf[TMPBUFLEN*2]; + + if (!task) + return -ESRCH; + length = scnprintf(tmpbuf, TMPBUFLEN*2, "%llu", audit_get_containerid(task)); + put_task_struct(task); + return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); +} + static ssize_t proc_containerid_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { @@ -1330,6 +1345,7 @@ static ssize_t proc_containerid_write(struct file *file, const char __user *buf, } static const struct file_operations proc_containerid_operations = { + .read = proc_containerid_read, .write = proc_containerid_write, .llseek = generic_file_llseek, }; @@ -2996,7 +3012,7 @@ static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, #ifdef CONFIG_AUDITSYSCALL REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), - REG("containerid", S_IWUSR, proc_containerid_operations), + REG("containerid", S_IWUSR|S_IRUSR, proc_containerid_operations), #endif #ifdef CONFIG_FAULT_INJECTION REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), @@ -3391,7 +3407,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask) #ifdef CONFIG_AUDITSYSCALL REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), - REG("containerid", S_IWUSR, proc_containerid_operations), + REG("containerid", S_IWUSR|S_IRUSR, proc_containerid_operations), #endif #ifdef CONFIG_FAULT_INJECTION REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), -- 1.8.3.1