The syscall number is stored in the same register as the syscall return
on amd64 (and possibly other architectures) and so it is impossible to
recover in the signal handler after the call has returned. This small
tweak delivers it in the `si_value` field of the signal, which is
sufficient to catch capability violations and emulate them with a call
to a more-privileged process in the signal handler.
Approved by: markj (mentor)
Reviewed by: kib, bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D29185
Implement dumping core for Linux binaries on amd64, for both
32- and 64-bit executables. Some bits are still missing.
This is based on a prototype by chuck@.
Reviewed By: kib
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D30019
This adds `sv_elf_core_osabi`, `sv_elf_core_abi_vendor`,
and `sv_elf_core_prepare_notes` fields to `struct sysentvec`,
and modifies imgact_elf.c to make use of them instead
of hardcoding FreeBSD-specific values. It also updates all
of the ABI definitions to preserve current behaviour.
This makes it possible to implement non-native ELF coredump
support without unnecessary code duplication. It will be used
for Linux coredumps.
Reviewed By: kib
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D30921
Assuming we can't run on i486, i586 class cpu, retire linux_kplatform var
and use hardcoded 'machine' value in linux_newuname().
I have added linux_kplatform for consistency with linux_platform which is
placed in to vdso to avoid excess copyout it on stack for AT_PLATFORM at
exec time.
This is the first stage of Linuxulator's vdso revision.
Reviewed by: trasz, imp
Differential Revision: https://reviews.freebsd.org/D30774
MFC after: 2 weeks
Require queueing of the signals with default action, and disable
dequeueing SIGCHLD on wait for live process.
Reported and tested by: dchagin
Reviewed by: dchagin, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D30675
The flag values seem to be the same between Linux and FreeBSD.
Comparing to a Linux VM on the same hardware, we're missing
HWCAP_EVTSTRM, HWCAP_CPUID, HWCAP_DCPOP, HWCAP_USCAT, HWCAP_PACA,
and HWCAP_PACG.
Reviewed By: mhorne, emaste
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D30540
Previously it would return "arm64", which was breaking build
for Linux kernel. While here, reshuffle entries in the auxv
vector to match real Linux.
Reviewed By: emaste
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D30500
This is both intuitive and required, as any previous breakpoint settings
may not be applicable to the new process.
Reported by: arichardson
Reviewed by: kib
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D29672
These are not stored in the trapframe so must be cleared explicitly.
This is similar to one of the MIPS changes in 822d2d6ac9.
Reviewed by: andrew
Obtained from: CheriBSD
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D28711
I noticed that many of the math-related tests were failing on AArch64.
After a lot of debugging, I noticed that the floating point exception flags
were not being reset when starting a new process. This change resets the
VFP inside exec_setregs() to ensure no VFP register state is leaked from
parent processes to children.
This commit also moves the clearing of fpcr that was added in 65618fdda0
from fork() to execve() since that makes more sense: fork() can retain
current register values, but execve() should result in a well-defined
clean state.
Reviewed By: andrew
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D29060
linux_shared_page_init() creates an object and grabs and maps a single
page to back the VDSO. When destroying the VDSO object, we failed to
destroy the mapping and free KVA. Fix this.
Reviewed by: kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28696
The definition was copied from amd64, but the layout of the struct
differs slightly between these platforms. This fixes spurious
`unsupported sigaction flag 0xXXXXXXXX` messages when executing some
Linux binaries on arm64.
Reviewed by: emaste
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D27460
Follow-up to r353959 and r368070: do the same for other architectures.
arm32 already seems to use its own .fnstart/.fnend directives, which
appear to be ARM-specific variants of the same thing. Likewise, MIPS
uses .frame directives.
Reviewed by: arichardson
Differential Revision: https://reviews.freebsd.org/D27387
Linux execve() gets audited as AUE_EXECVE as well, we should also interpret
the return from this correctly for the same reasoning as in r367002.
MFC with: r367002
This is a step towards facilitating jails with only Linux binaries.
Supporting emul_path adds path lookups which are completely spurious
if the binary at hand runs in a Linux-based root directory.
It defaults to on (== current behavior).
make -C /root/linux-5.3-rc8 -s -j 1 bzImage:
use_emul_path=1: 101.65s user 68.68s system 100% cpu 2:49.62 total
use_emul_path=0: 101.41s user 64.32s system 100% cpu 2:45.02 total
This effectively mirrors our libc implementation, but with minor fudging --
name needs to be copied in from userspace, so we just copy it straight into
stack-allocated memfd_name into the correct position rather than allocating
memory that needs to be cleaned up.
The sealing-related fcntl(2) commands, F_GET_SEALS and F_ADD_SEALS, have
also been implemented now that we support them.
Note that this implementation is still not quite at feature parity w.r.t.
the actual Linux version; some caveats, from my foggy memory:
- Need to implement SHM_GROW_ON_WRITE, default for memfd (in progress)
- LTP wants the memfd name exposed to fdescfs
- Linux allows open() of an fdescfs fd with O_TRUNC to truncate after dup.
(?)
Interested parties can install and run LTP from ports (devel/linux-ltp) to
confirm any fixes.
PR: 240874
Reviewed by: kib, trasz
Differential Revision: https://reviews.freebsd.org/D21845
in vanilla Linux git tree.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25385
