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.
This reapplies 3a522ba1bc with a fix for
the static assertion failure on i386.
Approved by: markj (mentor)
Reviewed by: kib, bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D29185
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
This makes it easier to compare the two. This involves moving
the mutex slightly lower down, but there should be no functional
changes.
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D30541
For now the Linux emulation layer uses in kernel ppoll(2) without
conversion of user supplied fd 'events', and does not convert the
kernel supplied fd 'revents'.
At least POLLRDHUP is handled by FreeBSD differently than by
Linux. Seems that Linux silencly ignores POLLRDHUP on non socket fd's
unlike FreeBSD, which does more strictly check and fails.
Rework the Linux ppoll, using kern_poll and converting 'events'
and 'revents' values.
While here, move poll events defines to the MI part of code as they
mostly identical on all arches except arm.
Differential Revision: https://reviews.freebsd.org/D30716
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
Retire ksiginfo_to_lsiginfo function, use siginfo_to_lsiginfo instead.
Convert rt_sigtimedwait siginfo variables to well known names.
MFC after: 2 weeks
If copyin family of routines fault, kernel does clear PSL.AC on the
fault entry, but the AC flag of the faulted frame is kept intact. Since
onfault handler is effectively jump, AC survives until syscall exit.
Reported by: m00nbsd, via Sony
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
admbugs: 975
Some of them were dereferencing the user pointer before disabling SMAP.
PR: 255591
Reviewed by: kib
Tested by: pitwuu@gmail.com
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30276
This fixes strace(1) erroneously reporting return values
as "Function not implemented", combined with reporting the binary
ABI as X32.
Very similar code in linux_ptrace_getregs() is left as it is - it's
probably wrong too, but I don't have a way to test it.
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29927
Previously we've returned the error from native ptrace(2), ENOMEM.
This confused Linux strace(2).
Reviewed By: emaste
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29925
This should be a no-op; the purpose of this is to reduce
a spurious difference between Linuxulator and Linux, to make
debugging core dumps slightly easier.
Note that AT_HWCAP2 we pass to Linux binaries is always 0,
instead of being equal to 'cpu_feature2'. This matches what
I've observed under Ubuntu Focal VM.
Reviewed By: chuck, dchagin
Sponsored By: EPSRC
Differential Revision: https://reviews.freebsd.org/D29609
instead of manually inlining it
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29687
- Use update_pcb_bases() when updating FS or GS base addresses to
permit use of FSBASE and GSBASE in Linux processes. This also sets
PCB_FULL_IRET. linux32 was setting PCB_32BIT which should be a
no-op (exec sets it).
- Remove write-only variables to construct unused segment descriptors
for linux32.
Reviewed by: kib
MFC after: 1 week
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D29026
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 ptrace(2) Linux man page claims the syscall returns ESRCH,
if the tracee is not stopped; the native ptrace(2) returns EBUSY.
Sponsored by: The FreeBSD Foundation
Foundation copyrights, approved by emaste@. It does not include
files which carry other people's copyrights; if you're one
of those people, feel free to make similar change.
Reviewed by: emaste, imp, gbe (manpages)
Differential Revision: https://reviews.freebsd.org/D26980
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
The former clobbers some registers that shouldn't be touched.
Reviewed by: kib (earlier version)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26406
