Without this, the signals are shown seemingly randomly in the output before
the final summary is shown. This is especially noticeable when there is
not much output from the application being traced.
Discussed with: jhb
Relnotes: yes
This is done by changing get_syscall() to either lookup the known syscall
or add it into the list with the default handlers for printing.
This also simplifies some code to not have to check if the syscall variable
is set or NULL.
Reviewed by: jhb
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D3792
- Refactor the interface between the ABI-independent code and the
ABI-specific backends. The backends now provide smaller hooks to
fetch system call arguments and return values. The rest of the
system call entry and exit handling that was previously duplicated
among all the backends has been moved to one place.
- Merge the loop when waiting for an event with the loop for handling stops.
This also means not emulating a procfs-like interface on top of ptrace().
Instead, use a single event loop that fetches process events via waitid().
Among other things this allows us to report the full 32-bit exit value.
- Use PT_FOLLOW_FORK to follow new child processes instead of forking a new
truss process for each new child. This allows one truss process to monitor
a tree of processes and truss -c should now display one total for the
entire tree instead of separate summaries per process.
- Use the recently added fields to ptrace_lwpinfo to determine the current
system call number and argument count. The latter is especially useful
and fixes a regression since the conversion from procfs. truss now
generally prints the correct number of arguments for most system calls
rather than printing extra arguments for any call not listed in the
table in syscalls.c.
- Actually check the new ABI when processes call exec. The comments claimed
that this happened but it was not being done (perhaps this was another
regression in the conversion to ptrace()). If the new ABI after exec
is not supported, truss detaches from the process. If truss does not
support the ABI for a newly executed process the process is killed
before it returns from exec.
- Along with the refactor, teach the various ABI-specific backends to
fetch both return values, not just the first. Use this to properly
report the full 64-bit return value from lseek(). In addition, the
handler for "pipe" now pulls the pair of descriptors out of the
return values (which is the true kernel system call interface) but
displays them as an argument (which matches the interface exported by
libc).
- Each ABI handler adds entries to a linker set rather than requiring
a statically defined table of handlers in main.c.
- The arm and mips system call fetching code was changed to follow the
same pattern as amd64 (and the in-kernel handler) of fetching register
arguments first and then reading any remaining arguments from the
stack. This should fix indirect system call arguments on at least
arm.
- The mipsn32 and n64 ABIs will now look for arguments in A4 through A7.
- Use register %ebp for the 6th system call argument for Linux/i386 ABIs
to match the in-kernel argument fetch code.
- For powerpc binaries on a powerpc64 system, fetch the extra arguments
on the stack as 32-bit values that are then copied into the 64-bit
argument array instead of reading the 32-bit values directly into the
64-bit array.
Reviewed by: kib (earlier version)
Tested on: amd64 (FreeBSD/amd64 & i386), i386, arm (earlier version)
Tested on: powerpc64 (FreeBSD/powerpc64 & powerpc)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D3575
with open_memstream() to build the string for each argument. This allows
for more complicated argument building without resorting to intermediate
malloc's, etc.
Related, the strsig*() functions no longer return allocated strings but
use a static global buffer instead.
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
allows userland application to use the following macros:
timespecclear, timespecisset, timespeccmp, timespecadd,
timespecsub;
timevalclear, timevalisset, timevalcmp.
MFC after: 1 month
When truss is detaching from very active process it is possible to
hang on waitpid(2) in restore_proc() forever, because
ptrace(PT_SYSCALL) must be called before detaching, to allow the
debugging process to continue execution. Also when truss called with
'-c' argument, it does not print anything after detach, because it
immediately exits from restore_proc().
To fix these two problems make detaching deferred, but then it is
impossible to detach from a process which does not do any system call.
To fix this issue use sigaction(2) instead of signal(3) to disable
SA_RESTART flag for waitpid(2) that makes it non-restartable. Remove
global variable child_pid, because now detaching is handled in context
where child's pid is known.
Reported by: mjg
Tested by: mjg, swills
Approved by: kib (mentor)
MFC after: 2 weeks
This matches the constants from <signal.h> with 'SIG' removed, which POSIX
requires kill and trap to accept and 'kill -l' to write.
'kill -l', 'trap', 'trap -l' output is now upper case.
In Turkish locales, signal names with an upper case 'I' are now accepted,
while signal names with a lower case 'i' are no longer accepted, and the
output of 'killall -l' now contains proper capital 'I' without dot instead
of a dotted capital 'I'.
with the -o option. Setting the flag for stderr (the default) could
cause the traced process to redirect stderr to a random file.
PR: bin/152151
Submitted by: ashish
MFC after: 5 days
been extensively tested. And the ELF64 stuff likely is not quite
right...
# There's a lot of cut-n-paste code here that could easily be
# refactored, at least for FreeBSD syscalls.
- Fix logic handling execve(). We will not be able to
obtain information otherwise.
- truss coredump [1].
- truss does not work against itself [2].
PR: bin/58970 [1], bin/45193 [2]
Submitted by: Howard Su
Approved by: re (kensmith)
rename, __getcwd, shutdown, getrlimit, setrlimit, _umtx_lock, _umtx_unlock,
pathconf, truncate, ftruncate, kill
- Decode more arguments of open, mprot, *stat, and fcntl.
- Convert all constant-macro and bitfield decoding to lookup tables; much
cleaner than previous code.
- Print the timestamp of process exit and signal reception when -d or -D are in
use
- Try six times with 1/2 second delay to debug the child
PR: bin/52190 (updated)
Submitted by: Dan Nelson <dnelson@allantgroup.com>
Approved by: alfred
type which is a String type that has no -s limitations applied to it.
Change most Strings in the code to Names and add a few extra syscalls,
namely munmap, read, rename and symlink. This was enough to facilitate
following file descriptor allocations in the code more easily and
getting a hint at what's being read/written from/to files. More
syscalls should really be added.
While here, fix an off-by-one bug in the buffer truncation code and
add a fflush so that truss's output reflects the syscall that the
program is stuck in.
Sponsored by: Sophos/Activestate
MFC after: 2 weeks
In my last change I made sure that the signal as reported from a truss
exit is the same as if truss wasn't between parent and trussed
program. I was smart enough to not have it coredump on SIGQUIT but it
didn't ocur to me SIGSEGV might cause a coredump, too :-)
So get rid of SIGQUIT extra hack and limit coredumpsize to zero
instead.
Tested: still works, correct signal reported. No more codedumps from
SIGSEGV in the trussed proces. This file compiles cleanly on AMD64
(sledge).
PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from:
MFC after:
o Syscall return values do not fit in int on 64-bit architectures.
Change the type of retval in <arch>_syscall_exit() to long and
change the prototype of said function to return a long as well.
o Change the prototype of print_syscall_ret() to take a long for
the return address and change the format string accordingly.
o Replace the code sequence
tmp = malloc(X);
sprintf(tmp, format, ...);
with X by definition too small on 64-bit platforms by
asprintf(&tmp, format, ...);
With these changes the output makes sense again, although it does
mess up the tabulation on ia64. Go widescreen...
Not tested on: alpha, sparc64.
depend on namespace pollution in <signal.h>. (truss shouldn't be
using timevals anyway, since it was implemented long after timevals
were obsoleted by timespecs.)