Add two new functions, sysdecode_abi_to_freebsd_errno() and
sysdecode_freebsd_to_abi_errno(), which convert errno values between
the native FreeBSD ABI and other supported ABIs. Note that the
mappings are not necessarily perfect meaning in some cases multiple
errors in one ABI might map to a single error in another ABI. In that
case, the reverse mapping will return one of the errors that maps, but
which error is non-deterministic.
Change truss to always report the raw error value to the user but
use libsysdecode to map it to a native errno value that can be used
with strerror() to generate a description. Previously truss reported
the "converted" error value. Now the user will always see the exact
error value that the application sees.
Change kdump to report the truly raw error value to the user. Previously
kdump would report the absolute value of the raw error value (so for
Linux binaries it didn't output the FreeBSD error value, but the positive
value of the Linux error). Now it reports the real (i.e. negative) error
value for Linux binaries. Also, use libsysdecode to convert the native
FreeBSD error reported in the ktrace record to the raw error used by the
ABI. This means that the Linux ABI can now be handled directly in
ktrsysret() and removes the need for linux_ktrsysret().
Reviewed by: bdrewery, kib
Helpful notes: wblock (manpage)
Differential Revision: https://reviews.freebsd.org/D5314
A new sysdecode_syscallname() function accepts a system call code and
returns a string of the corresponding name (or NULL if the code is
unknown). To support different process ABIs, the new function accepts a
value from a new sysdecode_abi enum as its first argument to select the
ABI in use. Current ABIs supported include FREEBSD (native binaries),
FREEBSD32, LINUX, LINUX32, and CLOUDABI64. Note that not all ABIs are
supported by all platforms. In general, a given ABI is only supported
if a platform can execute binaries for that ABI.
To simplify the implementation, libsysdecode's build reuses the
existing pre-generated files from the kernel source tree rather than
duplicating new copies of said files during the build.
kdump(1) and truss(1) now use these functions to map system call
identifiers to names. For kdump(1), a new 'syscallname()' function
consolidates duplicated code from ktrsyscall() and ktrsyscallret().
The Linux ABI no longer requires custom handling for ktrsyscall() and
linux_ktrsyscall() has been removed as a result.
Reviewed by: bdrewery
Differential Revision: https://reviews.freebsd.org/D4823
This is to make the Makefile more easily extendable for new ABIs.
This also makes several other subtle changes:
- The build now is given a list of ABIs to use based on the MACHINE_ARCH or
MACHINE_CPUARCH. These ABIs have a related path in sys/ that is used
to generate their syscalls. For each ABI to build check for a
ABI.c, MACHINE_ARCH-ABI.c, or a MACHINE_CPUARCH-ABI.c. This matches
the old behavior needed for archs such as powerpc* and mips*.
- The ABI source file selection allows for simpler assignment of common
ABIs such as "fbsd32" from sys/compat/freebsd32, or cloudabi64.
- Expand 'fbsd' to 'freebsd' everywhere for consistency.
- Split out the powerpc-fbsd.c file into a powerpc64-freebsd32.c to be more
like the amd64-freebsd32.c file and to more easily allow the auto-generation
of ABI handling to work.
- Rename 'syscalls.h' to 'fbsd_syscalls.h' to lessen the ambiguity and
avoid confusion with syscall.h (such as in r288997).
- For non-native syscall header files, they are now renamed to be
ABI_syscalls.h, where ABI is what ABI the Makefile is building.
- Remove all of the makesyscalls config files. The "native" one being
name i386.conf was a long outstanding bug. They were all the same
except for the data they generated, so now it is just auto-generated
as a build artifact.
- The syscalls array is now fixed to be static in the syscalls header to
remove the compiler warning about non-extern. This was worked around
in the aarch64-fbsd.c file but not the others.
- All syscall table names are now just 'syscallnames' since they don't
need to be different as they are all static in their own ABI files. The
alternative is to name them ABI_syscallnames which does not seem
necessary.
Reviewed by: ed, jhb
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D3851
- 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
arrays generically rather than duplicating a hack in all of the backends.
- Add two new system call argument types and use them instead of StringArray
for the argument and environment arguments execve and linux_execve.
- Honor the -a/-e flags in the handling of these new types.
- Instead of printing "<missing argument>" when the decoding is disabled,
print the raw pointer value.
- 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)
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
result buffer, so we need to format it ourselves. The problem is
that the length is stored as the return value from readlink, so we
need to pass the return value from our syscall into print_arg.
Motivated by: truss garbage on my screen from reading /etc/malloc.conf.
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.
1) Missing include.
2) Constness.
3) ANSIfication.
4) Avoid some shadowing.
5) Add/clarify some error messages.
6) Some int functions were using return without a value.
7) Mark some parameters as unused.
8) Cast a value we know is non-negative to a size_t before comparing.
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.)
some header files (e.g., <err.h>) include <machine/something.h>, and this
will not pick up the right header files, so it may be removed eventually
anyway. But some people who are not willing to build the right way
apparantly want this, so this is for them.
Correct usage: one of {-p pid, command} is required.
Open output file when command line is fully analyzed: incorrect `truss -o f'
command does not create an empty file anymore.
