On 2018-05-09 11:46, Paul Moore wrote: > On Fri, May 4, 2018 at 4:54 PM, Richard Guy Briggs <rgb@xxxxxxxxxx> wrote: > > The audit-related parameters in struct task_struct should ideally be > > collected together and accessed through a standard audit API. > > > > Collect the existing loginuid, sessionid and audit_context together in a > > new struct audit_task_info pointer called "audit" in struct task_struct. > > > > Use kmem_cache to manage this pool of memory. > > Un-inline audit_free() to be able to always recover that memory. > > > > See: https://github.com/linux-audit/audit-kernel/issues/81 > > > > Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx> > > --- > > MAINTAINERS | 2 +- > > include/linux/audit.h | 8 ++++---- > > include/linux/audit_task.h | 31 +++++++++++++++++++++++++++++++ > > include/linux/sched.h | 6 ++---- > > init/init_task.c | 8 ++++++-- > > kernel/auditsc.c | 4 ++-- > > 6 files changed, 46 insertions(+), 13 deletions(-) > > create mode 100644 include/linux/audit_task.h > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index 0a1410d..8c7992d 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -2510,7 +2510,7 @@ L: linux-audit@xxxxxxxxxx (moderated for non-subscribers) > > W: https://github.com/linux-audit > > T: git git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit.git > > S: Supported > > -F: include/linux/audit.h > > +F: include/linux/audit*.h > > F: include/uapi/linux/audit.h > > F: kernel/audit* > > > > diff --git a/include/linux/audit.h b/include/linux/audit.h > > index dba0d45..1324969 100644 > > --- a/include/linux/audit.h > > +++ b/include/linux/audit.h > > @@ -237,11 +237,11 @@ extern void __audit_inode_child(struct inode *parent, > > > > static inline void audit_set_context(struct task_struct *task, struct audit_context *ctx) > > { > > - task->audit_context = ctx; > > + task->audit.ctx = ctx; > > } > > static inline struct audit_context *audit_context(struct task_struct *task) > > { > > - return task->audit_context; > > + return task->audit.ctx; > > } > > static inline bool audit_dummy_context(void) > > { > > @@ -330,12 +330,12 @@ extern int auditsc_get_stamp(struct audit_context *ctx, > > > > static inline kuid_t audit_get_loginuid(struct task_struct *tsk) > > { > > - return tsk->loginuid; > > + return tsk->audit.loginuid; > > } > > > > static inline unsigned int audit_get_sessionid(struct task_struct *tsk) > > { > > - return tsk->sessionid; > > + return tsk->audit.sessionid; > > } > > > > extern void __audit_ipc_obj(struct kern_ipc_perm *ipcp); > > diff --git a/include/linux/audit_task.h b/include/linux/audit_task.h > > new file mode 100644 > > index 0000000..d4b3a20 > > --- /dev/null > > +++ b/include/linux/audit_task.h > > @@ -0,0 +1,31 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* audit_task.h -- definition of audit_task_info structure > > + * > > + * Copyright 2018 Red Hat Inc., Raleigh, North Carolina. > > + * 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 as published by > > + * the Free Software Foundation; either version 2 of the License, or > > + * (at your option) any later version. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * Written by Richard Guy Briggs <rgb@xxxxxxxxxx> > > + * > > + */ > > + > > +#ifndef _LINUX_AUDIT_TASK_H_ > > +#define _LINUX_AUDIT_TASK_H_ > > + > > +struct audit_context; > > +struct audit_task_info { > > + kuid_t loginuid; > > + unsigned int sessionid; > > + struct audit_context *ctx; > > +}; > > + > > +#endif > > diff --git a/include/linux/sched.h b/include/linux/sched.h > > index b3d697f..b58eca0 100644 > > --- a/include/linux/sched.h > > +++ b/include/linux/sched.h > > @@ -27,9 +27,9 @@ > > #include <linux/signal_types.h> > > #include <linux/mm_types_task.h> > > #include <linux/task_io_accounting.h> > > +#include <linux/audit_task.h> > > > > /* task_struct member predeclarations (sorted alphabetically): */ > > -struct audit_context; > > struct backing_dev_info; > > struct bio_list; > > struct blk_plug; > > @@ -832,10 +832,8 @@ struct task_struct { > > > > struct callback_head *task_works; > > > > - struct audit_context *audit_context; > > #ifdef CONFIG_AUDITSYSCALL > > - kuid_t loginuid; > > - unsigned int sessionid; > > + struct audit_task_info audit; > > #endif > > Considering that the audit_context pointer is now in the > audit_task_info struct, should the audit_task_info struct be placed > outside the CONFIG_AUDITSYSCALL protections? Or rather, shouldn't the > CONFIG_AUDITSYSCALL protections be moved inside audit_task_info or > removed entirely? Well, I wondered about that anyways. audit_context is only meaningful in CONFIG_AUDIT_SYSCALL, and loginuid and sessionid were already there, so the whole thing should be inside, but given that CONFIG_AUDIT_SYSCALL is forced on when CONFIG_AUDIT is set I don't see that it matters. Perhaps CONFIG_AUDIT_SYSCALL should be ripped out completely and the code flattenned to the CONFIG_AUDIT case. I see your point though, moving CONFIG_AUDIT_SYSCALL protections to within the audit_task_info struct definition makes more sense than this above. > > diff --git a/init/init_task.c b/init/init_task.c > > index c788f91..d33260d 100644 > > --- a/init/init_task.c > > +++ b/init/init_task.c > > @@ -9,6 +9,7 @@ > > #include <linux/init.h> > > #include <linux/fs.h> > > #include <linux/mm.h> > > +#include <linux/audit.h> > > > > #include <asm/pgtable.h> > > #include <linux/uaccess.h> > > @@ -118,8 +119,11 @@ struct task_struct init_task > > .thread_group = LIST_HEAD_INIT(init_task.thread_group), > > .thread_node = LIST_HEAD_INIT(init_signals.thread_head), > > #ifdef CONFIG_AUDITSYSCALL > > - .loginuid = INVALID_UID, > > - .sessionid = AUDIT_SID_UNSET, > > + .audit = { > > + .loginuid = INVALID_UID, > > + .sessionid = AUDIT_SID_UNSET, > > + .ctx = NULL, > > + }, > > #endif > > #ifdef CONFIG_PERF_EVENTS > > .perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex), > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index f294e4a..b5d8bff 100644 > > --- a/kernel/auditsc.c > > +++ b/kernel/auditsc.c > > @@ -2068,8 +2068,8 @@ int audit_set_loginuid(kuid_t loginuid) > > sessionid = (unsigned int)atomic_inc_return(&session_id); > > } > > > > - task->sessionid = sessionid; > > - task->loginuid = loginuid; > > + task->audit.sessionid = sessionid; > > + task->audit.loginuid = loginuid; > > out: > > audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc); > > return rc; > > -- > > 1.8.3.1 > > -- > paul moore > www.paul-moore.com - RGB -- Richard Guy Briggs <rgb@xxxxxxxxxx> Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada IRC: rgb, SunRaycer Voice: +1.647.777.2635, Internal: (81) 32635
