Commit fd593511 authored by Beau Belgrave's avatar Beau Belgrave Committed by Steven Rostedt (Google)
Browse files

tracing/user_events: Track fork/exec/exit for mm lifetime 

During tracefs discussions it was decided instead of requiring a mapping
within a user-process to track the lifetime of memory descriptors we
should hook the appropriate calls. Do this by adding the minimal stubs
required for task fork, exec, and exit. Currently this is just a NOP.
Future patches will implement these calls fully.

Link: https://lkml.kernel.org/r/20230328235219.203-3-beaub@linux.microsoft.com



Suggested-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: default avatarBeau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent e5a26a40

fs/exec.c

+2 −0
Original line number Diff line number Diff line
@@ -65,6 +65,7 @@ 
#include <linux/syscall_user_dispatch.h>

#include <linux/coredump.h>

#include <linux/time_namespace.h>

#include <linux/user_events.h>



#include <linux/uaccess.h>

#include <asm/mmu_context.h>
@@ -1859,6 +1860,7 @@ static int bprm_execve(struct linux_binprm *bprm, 
	current->fs->in_exec = 0;

	current->in_execve = 0;

	rseq_execve(current);

	user_events_execve(current);

	acct_update_integrals(current);

	task_numa_free(current, false);

	return retval;

include/linux/sched.h

+5 −0
Original line number Diff line number Diff line
@@ -69,6 +69,7 @@ struct sighand_struct; 
struct signal_struct;

struct task_delay_info;

struct task_group;

struct user_event_mm;



/*

 * Task state bitmask. NOTE! These bits are also
@@ -1528,6 +1529,10 @@ struct task_struct { 
	union rv_task_monitor		rv[RV_PER_TASK_MONITORS];

#endif



#ifdef CONFIG_USER_EVENTS

	struct user_event_mm		*user_event_mm;

#endif



	/*

	 * New fields for task_struct should be added above here, so that

	 * they are included in the randomized portion of task_struct.

include/linux/user_events.h

+18 −0
Original line number Diff line number Diff line
@@ -11,4 +11,22 @@ 


#include <uapi/linux/user_events.h>



#ifdef CONFIG_USER_EVENTS

struct user_event_mm {

};

#endif



static inline void user_events_fork(struct task_struct *t,

				    unsigned long clone_flags)

{

}



static inline void user_events_execve(struct task_struct *t)

{

}



static inline void user_events_exit(struct task_struct *t)

{

}



#endif /* _LINUX_USER_EVENTS_H */

kernel/exit.c

+2 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ 
#include <linux/kprobes.h>

#include <linux/rethook.h>

#include <linux/sysfs.h>

#include <linux/user_events.h>



#include <linux/uaccess.h>

#include <asm/unistd.h>
@@ -818,6 +819,7 @@ void __noreturn do_exit(long code) 


	coredump_task_exit(tsk);

	ptrace_event(PTRACE_EVENT_EXIT, code);

	user_events_exit(tsk);



	validate_creds_for_do_exit(tsk);

kernel/fork.c

+2 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ 
#include <linux/io_uring.h>

#include <linux/bpf.h>

#include <linux/stackprotector.h>

#include <linux/user_events.h>



#include <asm/pgalloc.h>

#include <linux/uaccess.h>
@@ -2505,6 +2506,7 @@ static __latent_entropy struct task_struct *copy_process( 


	trace_task_newtask(p, clone_flags);

	uprobe_copy_process(p, clone_flags);

	user_events_fork(p, clone_flags);



	copy_oom_score_adj(clone_flags, p);