user/sven/linux.git/include/linux/tracehook.h, branch v3.12.33

trim task_work: get rid of hlist

2012-07-22T19:57:55Z

layout based on Oleg's suggestion; single-linked list, task->task_works points to the last element, forward pointer from said last element points to head. I'd still prefer much more regular scheme with two pointers in task_work, but... Signed-off-by: Al Viro

keys: kill the dummy key_replace_session_keyring()

2012-05-24T02:11:31Z

After the previouse change key_replace_session_keyring() becomes a nop. Remove the dummy definition in key.h and update the callers in arch/*/kernel/signal.c. Signed-off-by: Oleg Nesterov Acked-by: David Howells Cc: Thomas Gleixner Cc: Richard Kuo Cc: Linus Torvalds Cc: Alexander Gordeev Cc: Chris Zankel Cc: David Smith Cc: "Frank Ch. Eigler" Cc: Geert Uytterhoeven Cc: Larry Woodman Cc: Peter Zijlstra Cc: Tejun Heo Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Al Viro

task_work_add: generic process-context callbacks

2012-05-24T02:09:21Z

Provide a simple mechanism that allows running code in the (nonatomic) context of the arbitrary task. The caller does task_work_add(task, task_work) and this task executes task_work->func() either from do_notify_resume() or from do_exit(). The callback can rely on PF_EXITING to detect the latter case. "struct task_work" can be embedded in another struct, still it has "void *data" to handle the most common/simple case. This allows us to kill the ->replacement_session_keyring hack, and potentially this can have more users. Performance-wise, this adds 2 "unlikely(!hlist_empty())" checks into tracehook_notify_resume() and do_exit(). But at the same time we can remove the "replacement_session_keyring != NULL" checks from arch/*/signal.c and exit_creds(). Note: task_work_add/task_work_run abuses ->pi_lock. This is only because this lock is already used by lookup_pi_state() to synchronize with do_exit() setting PF_EXITING. Fortunately the scope of this lock in task_work.c is really tiny, and the code is unlikely anyway. Signed-off-by: Oleg Nesterov Acked-by: David Howells Cc: Thomas Gleixner Cc: Richard Kuo Cc: Linus Torvalds Cc: Alexander Gordeev Cc: Chris Zankel Cc: David Smith Cc: "Frank Ch. Eigler" Cc: Geert Uytterhoeven Cc: Larry Woodman Cc: Peter Zijlstra Cc: Tejun Heo Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Al Viro

move key_repace_session_keyring() into tracehook_notify_resume()

2012-05-24T02:09:20Z

Signed-off-by: Al Viro

TIF_NOTIFY_RESUME is defined on all targets now

2012-05-24T02:09:19Z

Signed-off-by: Al Viro

ptrace: the killed tracee should not enter the syscall

2012-03-23T23:58:40Z

Another old/known problem. If the tracee is killed after it reports syscall_entry, it starts the syscall and debugger can't control this. This confuses the users and this creates the security problems for ptrace jailers. Change tracehook_report_syscall_entry() to return non-zero if killed, this instructs syscall_trace_enter() to abort the syscall. Reported-by: Chris Evans Tested-by: Indan Zupancic Signed-off-by: Oleg Nesterov Cc: Denys Vlasenko Cc: Tejun Heo Cc: Pedro Alves Cc: Jan Kratochvil Cc: Steven Rostedt Cc: Frederic Weisbecker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kill tracehook_notify_death()

2011-06-27T18:30:08Z

Kill tracehook_notify_death(), reimplement the logic in its caller, exit_notify(). Also, change the exec_id's check to use thread_group_leader() instead of task_detached(), this is more clear. This logic only applies to the exiting leader, a sub-thread must never change its exit_signal. Note: when the traced group leader exits the exit_signal-or-SIGCHLD logic looks really strange: - we notify the tracer even if !thread_group_empty() but do_wait(WEXITED) can't work until all threads exit - if the tracer is real_parent, it is not clear why can't we use ->exit_signal event if !thread_group_empty() -v2: do not try to fix the 2nd oddity to avoid the subtle behavior change mixed with reorganization, suggested by Tejun. Signed-off-by: Oleg Nesterov Reviewed-by: Tejun Heo

ptrace: s/tracehook_tracer_task()/ptrace_parent()/

2011-06-22T17:26:29Z

tracehook.h is on the way out. Rename tracehook_tracer_task() to ptrace_parent() and move it from tracehook.h to ptrace.h. Signed-off-by: Tejun Heo Cc: Christoph Hellwig Cc: John Johansen Cc: Stephen Smalley Signed-off-by: Oleg Nesterov

ptrace: kill clone/exec tracehooks

2011-06-22T17:26:29Z

At this point, tracehooks aren't useful to mainline kernel and mostly just add an extra layer of obfuscation. Although they have comments, without actual in-kernel users, it is difficult to tell what are their assumptions and they're actually trying to achieve. To mainline kernel, they just aren't worth keeping around. This patch kills the following clone and exec related tracehooks. tracehook_prepare_clone() tracehook_finish_clone() tracehook_report_clone() tracehook_report_clone_complete() tracehook_unsafe_exec() The changes are mostly trivial - logic is moved to the caller and comments are merged and adjusted appropriately. The only exception is in check_unsafe_exec() where LSM_UNSAFE_PTRACE* are OR'd to bprm->unsafe instead of setting it, which produces the same result as the field is always zero on entry. It also tests p->ptrace instead of (p->ptrace & PT_PTRACED) for consistency, which also gives the same result. This doesn't introduce any behavior change. Signed-off-by: Tejun Heo Cc: Christoph Hellwig Signed-off-by: Oleg Nesterov

ptrace: kill trivial tracehooks

2011-06-22T17:26:28Z

At this point, tracehooks aren't useful to mainline kernel and mostly just add an extra layer of obfuscation. Although they have comments, without actual in-kernel users, it is difficult to tell what are their assumptions and they're actually trying to achieve. To mainline kernel, they just aren't worth keeping around. This patch kills the following trivial tracehooks. * Ones testing whether task is ptraced. Replace with ->ptrace test. tracehook_expect_breakpoints() tracehook_consider_ignored_signal() tracehook_consider_fatal_signal() * ptrace_event() wrappers. Call directly. tracehook_report_exec() tracehook_report_exit() tracehook_report_vfork_done() * ptrace_release_task() wrapper. Call directly. tracehook_finish_release_task() * noop tracehook_prepare_release_task() tracehook_report_death() This doesn't introduce any behavior change. Signed-off-by: Tejun Heo Cc: Christoph Hellwig Cc: Martin Schwidefsky Signed-off-by: Oleg Nesterov