user/sven/linux.git/include/linux/ptrace.h, branch v4.1.6

exit: ptrace: shift "reap dead" code from exit_ptrace() to forget_original_parent()

2014-12-11T01:41:10Z

Now that forget_original_parent() uses ->ptrace_entry for EXIT_DEAD tasks, we can simply pass "dead_children" list to exit_ptrace() and remove another release_task() loop. Plus this way we do not need to drop and reacquire tasklist_lock. Also shift the list_empty(ptraced) check, if we want this optimization it makes sense to eliminate the function call altogether. Signed-off-by: Oleg Nesterov Cc: Aaron Tomlin Cc: Alexey Dobriyan Cc: "Eric W. Biederman" , Cc: Sterling Alexander Cc: Peter Zijlstra Cc: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ptrace,x86: force IRET path after a ptrace_stop()

2014-07-04T00:27:23Z

The 'sysret' fastpath does not correctly restore even all regular registers, much less any segment registers or reflags values. That is very much part of why it's faster than 'iret'. Normally that isn't a problem, because the normal ptrace() interface catches the process using the signal handler infrastructure, which always returns with an iret. However, some paths can get caught using ptrace_event() instead of the signal path, and for those we need to make sure that we aren't going to return to user space using 'sysret'. Otherwise the modifications that may have been done to the register set by the tracer wouldn't necessarily take effect. Fix it by forcing IRET path by setting TIF_NOTIFY_RESUME from arch_ptrace_stop_needed() which is invoked from ptrace_stop(). Signed-off-by: Tejun Heo Reported-by: Andy Lutomirski Acked-by: Oleg Nesterov Suggested-by: Linus Torvalds Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds

ptrace: fix fork event messages across pid namespaces

2014-06-06T23:08:11Z

When tracing a process in another pid namespace, it's important for fork event messages to contain the child's pid as seen from the tracer's pid namespace, not the parent's. Otherwise, the tracer won't be able to correlate the fork event with later SIGTRAP signals it receives from the child. We still risk a race condition if a ptracer from a different pid namespace attaches after we compute the pid_t value. However, sending a bogus fork event message in this unlikely scenario is still a vast improvement over the status quo where we always send bogus fork event messages to debuggers in a different pid namespace than the forking process. Signed-off-by: Matthew Dempsky Acked-by: Oleg Nesterov Cc: Kees Cook Cc: Julien Tinnes Cc: Roland McGrath Cc: Jan Kratochvil Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ptrace: revert "Prepare to fix racy accesses on task breakpoints"

2013-07-09T17:33:26Z

This reverts commit bf26c018490c ("Prepare to fix racy accesses on task breakpoints"). The patch was fine but we can no longer race with SIGKILL after commit 9899d11f6544 ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL"), the __TASK_TRACED tracee can't be woken up and ->ptrace_bps[] can't go away. Now that ptrace_get_breakpoints/ptrace_put_breakpoints have no callers, we can kill them and remove task->ptrace_bp_refcnt. Signed-off-by: Oleg Nesterov Acked-by: Frederic Weisbecker Acked-by: Michael Neuling Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Jan Kratochvil Cc: Paul Mackerras Cc: Paul Mundt Cc: Will Deacon Cc: Prasad Cc: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ia64: kill thread_matches(), unexport ptrace_check_attach()

2013-01-20T20:26:05Z

The ia64 function "thread_matches()" has no users since commit e868a55c2a8c ("[IA64] remove find_thread_for_addr()"). Remove it. This allows us to make ptrace_check_attach() static to kernel/ptrace.c, which is good since we'll need to change the semantics of it and fix up all the callers. Signed-off-by: Oleg Nesterov Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

2012-12-21T02:05:28Z

Pull signal handling cleanups from Al Viro: "sigaltstack infrastructure + conversion for x86, alpha and um, COMPAT_SYSCALL_DEFINE infrastructure. Note that there are several conflicts between "unify SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline; resolution is trivial - just remove definitions of SS_ONSTACK and SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and include/uapi/linux/signal.h contains the unified variant." Fixed up conflicts as per Al. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: alpha: switch to generic sigaltstack new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those generic compat_sys_sigaltstack() introduce generic sys_sigaltstack(), switch x86 and um to it new helper: compat_user_stack_pointer() new helper: restore_altstack() unify SS_ONSTACK/SS_DISABLE definitions new helper: current_user_stack_pointer() missing user_stack_pointer() instances Bury the conditionals from kernel_thread/kernel_execve series COMPAT_SYSCALL_DEFINE: infrastructure

new helper: current_user_stack_pointer()

2012-12-19T23:07:39Z

Cross-architecture equivalent of rdusp(); default is user_stack_pointer(current_pt_regs()) - that works for almost all platforms that have usp saved in pt_regs. The only exception from that is ia64 - we want memory stack, not the backing store for register one. Signed-off-by: Al Viro

ptrace: introduce PTRACE_O_EXITKILL

2012-12-18T01:15:22Z

Ptrace jailers want to be sure that the tracee can never escape from the control. However if the tracer dies unexpectedly the tracee continues to run in potentially unsafe mode. Add the new ptrace option PTRACE_O_EXITKILL. If the tracer exits it sends SIGKILL to every tracee which has this bit set. Note that the new option is not equal to the last-option << 1. Because currently all options have an event, and the new one starts the eventless group. It uses the random 20 bit, so we have the room for 12 more events, but we can also add the new eventless options below this one. Suggested by Amnon Shiloh. Signed-off-by: Oleg Nesterov Tested-by: Amnon Shiloh Cc: Denys Vlasenko Cc: Michael Kerrisk Cc: Serge Hallyn Cc: Chris Evans Cc: David Howells Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

get rid of ptrace_signal_deliver() arguments

2012-11-29T05:01:24Z

the first one is equal to signal_pt_regs(), the second is never used (and always NULL, while we are at it). Signed-off-by: Al Viro

new helper: signal_pt_regs()

2012-11-29T05:01:23Z

Always equal to task_pt_regs(current); defined only when we are in signal delivery. It may be different from current_pt_regs() - e.g. architectures like m68k may have pt_regs location on exception different from that on a syscall and signals (just as ptrace handling) may happen on exceptions as well as on syscalls. When they are equal, it's often better to have signal_pt_regs defined (in asm/ptrace.h) as current_pt_regs - that tends to be optimized better than default would be. However, optimisation is the only reason why we might want an arch-specific definition; if current_pt_regs() and task_pt_regs(current) have different values, the latter one is right. Signed-off-by: Al Viro