If we write a byte character into a pointer, a compiler can emit a
read-modify-write operation, especially when a CPU cannot access directly
a character wide address.
In this scenario calling mmap(2) with PROT_WRITE, without PROT_READ will
emit unexpected trap.
There are two possible workarounds for this issue:
- write register wide memory without rmw sequence,
- mark the region with additional protection PROT_READ
Both work for NetBSD/alpha.
Go for the latter as perhaps more safe for dump compilers emitting rmw
sequences.
Investigated by <martin>
These crash signals are crucial for proper handling of abnormal conditions
in a program. The additional purpose of these tests it to assure the proper
handling of these signals for the coming ptrace(2)-related changes in the
signal routing code.
Add a stub for ILL scenarios.
All tests pass (on amd64).
The shell ATF script contains duplicated code. There should be a way to
deduplicate it, without rewrite to C.
Sponsored by <The NetBSD Foundation>
There are at least four types of SIGTRAP events:
- software/hardware single step (trace trap)
- software breakpoint
- hardware breakpoint/watchpoint
- kernel event (exec, fork, vfork, vfork-done, lwp-create, lwp-exit)
A program can execute software breakpoint without the context of being
traced and this is a regular crash signal emitting SIGTRAP (TRAP_BRKPT).
Rename original trap_* tests (trap_simple, trap_handle, trap_mask,
trap_handle_recurse and trap_ignore) to segv_* tests and restrict them for
SIGSEGV.
Add new tests: trap_* testing the same scenarios as segv_ ones, however
verifying the software breakpoint trap (SIGTRAP).
Keep the original name of h_segv.c, and extend it for software breakpoint
events.
The purpose of these tests is to verify SIGTRAP kernel paths without the
ptrace(2) context.
All tests pass.
Sponsored by <The NetBSD Foundation>
New tests attempting to kill, stop, drop or revive a zombie:
- signal1 (SIGKILL)
- signal2 (SIGSTOP)
- signal3 (SIGABRT)
- signal4 (SIGHUP)
- signal5 (SIGCONT)
New test race1 verifying whether there are any kernel races when processing
signals to zombies, executing in a loop for 5 seconds.
These tests were inspired by a kernel unexpected behavior when a lookup
of a dying process could result in two detected entities once as an alive
process and once as a zombie.
race1 is similar to t_ptrace_wait* race1, however without ptrace(2) involved.
Sponsored by <The NetBSD Foundation>
with FreeBSD)
* Fix a broken call to open(2) with O_CREAT and no permission argument.
* ANSIfy function definitions.
* Improve failure messages.
From freebsd.org via Brooks Davis - Thanks!
This aims to remove MD-specific tests files for ptrace(2).
Prefix i386 and amd64 tests with unique strings "i386_" and "x86_64_".
This removes conflicts with generic tests.
Sponsored by <The NetBSD Foundation>
Change:
Test must be run with securelevel >= 1
To:
Test must be run with securelevel >= 0
In attach_pid1_securelevel.
Sponsored by <The NetBSD Foundation>
Move common function code into shared subroutine.
While there remove checks for defined(HAVE_DBREGS). All x86 ports offer
debug register accessors.
Sponsored by <The NetBSD Foundation>
PR kern/52117 ptrace(2) PTRACE_FORK fails on some platforms
Add message similar to:
We expect two SIGTRAP events, for child 22199 (TRAP_CHLD,
pe_report_event=PTRACE_FORK, state.pe_other_pid=child2) and for child2
(TRAP_CHLD, pe_report_event=PTRACE_FORK, state.pe_other_pid=child)
This should make the expected behavior more clear.
Sponsored by <The NetBSD Foundation>
There is a definition of PT_STEP for userland, but no implementation
in the kernel.
PR kern/52119 PT_STEP not supported on arm 32-bit
Sponsored by <The NetBSD Foundation>
Mark timeout for this test 5 sec. It sometimes works sometimes does not.
Add a local sleep(3) at the end to get consisten report about timeouting
always.
PR kern/51995
Sponsored by <The NetBSD Foundation>
PR kern/52117 ptrace(2) PTRACE_FORK fails on some platforms
These tests work on amd64, i386 and xen.
They are part of t_ptrace_wait*.
Sponsored by <The NetBSD Foundation>
This test is marked as PR kern/51918.
Timeout has been reported on i386, amd64, alpha, sparc, sparc64, evbarm.
xen.
Sponsored by <The NetBSD Foundation>
[v]fork() produces pid==1 (init) (if it were useful to test that, an
entirely different test would be appropriate) change the tests so
they check for [v]fork() failure, as probably intended, instead.
Mark this test broken with kern/52012 as the tracee does not stop on syscall
entry. Check for siginfo(2) in syscall1 and unveil two new bugs.
PR kern/52012: PT_SYSCALL does not stop on syscall entry
PR kern/52018: ptrace(2) PT_SYSCALL generates SIGTRAP without si_code
PR kern/52019: ptrace(2) PT_SYSCALL generate SIGTRAP to the parent but
returns SIGSTOP in PT_GET_SIGINFO
Sponsored by <The NetBSD Foundation>
resume1:
PR kern/51995 ptrace(2) PT_RESUME is not reliable
syscallemu1:
PR kern/52012 PT_SYSCALL does not stop on syscall entry
Sponsored by <The NetBSD Foundation>
syscallemu1:
Verify that exit(2) can be intercepted with PT_SYSCALLEMU
This test is failing as PT_SYSCALL does not stop the process on syscall
entry. This renders PT_SYSCALL broken on NetBSD.
Sponsored by <The NetBSD Foundation>
syscall1:
Verify that getpid(2) can be traced with PT_SYSCALL
Enforce usage of syscall(2), it should prevent failing on any possible
optimizations in future as a libc can ship this information not through
syscall (shared struct with kernel or similar).
Sponsored by <The NetBSD Foundation>
Use proper check for LW_SYSTEM, don't depend on PT_GETREGS/PT_SETREGS.
Don't allow to mask SA_CANTMASK signals with PT_SET_SIGMASK (this covers
SIGSTOP and SIGKILL).
Add new ATF tests:
- setsigmask5
Verify that sigmask cannot be set to SIGKILL
- setsigmask6
Verify that sigmask cannot be set to SIGSTOP
Sponsored by <The NetBSD Foundation>
Introduce new API for debuggers to allow/prevent execution of the specified
thread.
New ptrace(2) operations:
PT_RESUME Allow execution of a specified thread, change its state
from suspended to continued. The addr argument is unused.
The data argument specifies the LWP ID.
This call is equivalent to _lwp_continue(2) called by a
traced process. This call does not change the general
process state from stopped to continued.
PT_SUSPEND Prevent execution of a specified thread, change its state
from continued to suspended. The addr argument is unused.
The data argument specifies the requested LWP ID.
This call is equivalent to _lwp_suspend(2) called by a
traced process. This call does not change the general
process state from continued to stopped.
This interface is modeled after FreeBSD, however with NetBSD specific arguments
passed to ptrace(2) -- FreeBSD passes only thread id, NetBSD passes process and
thread id.
Extend PT_LWPINFO operation in ptrace(2) to report suspended threads. In the
ptrace_lwpinfo structure in pl_event next to PL_EVENT_NONE and PL_EVENT_SIGNAL
add new value PL_EVENT_SUSPENDED.
Add new errno(2) value EDEADLK that might be returned by ptrace(2). It prevents
dead-locking in a scenario of resuming a process or thread that is prevented
from execution. This fixes bug that old API was vulnerable to this scenario.
Kernel bump delayed till introduction of PT_GETDBREGS/PT_SETDBREGS soon.
Add new ATF tests:
- resume1
Verify that a thread can be suspended by a debugger and later
resumed by the debugger
- suspend1
Verify that a thread can be suspended by a debugger and later
resumed by a tracee
- suspend2
Verify that the while the only thread within a process is
suspended, the whole process cannot be unstopped
Sponsored by <The NetBSD Foundation>
kamil