thread_info.syscall is used by syscall_get_nr to supply syscall nr
over a thread stack frame.
Previously, thread_info.syscall is only saved at syscall_trace_enter
when syscall tracing is enabled. However rest of the kernel code do
expect syscall_get_nr to be available without syscall tracing. The
previous design breaks collect_syscall.
Move saving process to syscall entry to fix it.
Reported-by: Xi Ruoyao <xry111@xry111.site>
Link: https://github.com/util-linux/util-linux/issues/2867
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Many architectures duplicate similar shell scripts.
This commit converts mips to use scripts/syscalltbl.sh. This also
unifies syscall_table_32_o32.h and syscall_table_64_o32.h into
syscall_table_o32.h.
The offset parameters are unneeded here; __SYSCALL(nr, entry) is defined
as 'PTR entry', so the parameter 'nr' is not used in the first place.
With this commit, syscall tables and generated files are straight
mapped, which makes things easier to understand.
syscall_n32.tbl --> syscall_table_n32.h
syscall_n64.tbl --> syscall_table_n64.h
syscall_o32.tbl --> syscall_table_o32.h
Then, the abi parameters are also unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
The MIPS sysmips system call handler may return directly from the
MIPS_ATOMIC_SET case (mips_atomic_set()) to syscall_exit. This path
restores the static (callee saved) registers, however they won't have
been saved on entry to the system call.
Use the save_static_function() macro to create a __sys_sysmips wrapper
function which saves the static registers before calling sys_sysmips, so
that the correct static register state is restored by syscall_exit.
Fixes: f1e39a4a61 ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16149/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit d218af7849 ("MIPS: scall: Always run the seccomp syscall
filters") modified the syscall code to always call the seccomp filters,
but missed the case where a filter may redirect the syscall, as
revealed by the seccomp_bpf self test.
The syscall path now restores the syscall from the stack after the
filter rather than saving it locally. Syscall number checking and
syscall function table lookup is done after the filter may have run such
that redirected syscalls are also checked, and executed.
The regular path of syscall number checking and pointer lookup is also
made more consistent between ABIs with scall64-64.S being the reference.
With this patch in place, the seccomp_bpf self test now passes
TRACE_syscall.syscall_redirected and TRACE_syscall.syscall_dropped on
all MIPS ABIs.
Fixes: d218af7849 ("MIPS: scall: Always run the seccomp syscall filters")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Eric B Munson <emunson@akamai.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: IMG-MIPSLinuxKerneldevelopers@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12916/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS syscall handler code used to return -ENOSYS on invalid
syscalls. Whilst this is expected, it caused problems for seccomp
filters because the said filters never had the change to run since
the code returned -ENOSYS before triggering them. This caused
problems on the chromium testsuite for filters looking for invalid
syscalls. This has now changed and the seccomp filters are always
run even if the syscall is invalid. We return -ENOSYS once we
return from the seccomp filters. Moreover, similar codepaths have
been merged in the process which simplifies somewhat the overall
syscall code.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls (o32)")
fixed indirect system calls on O32 but it also introduced a bug for MIPS64
where it erroneously modified the v0 (syscall) register with the assumption
that the sycall offset hasn't been taken into consideration. This breaks
seccomp on MIPS64 n64 and n32 ABIs. We fix this by replacing the addition
with a move instruction.
Fixes: 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls (o32)")
Cc: <stable@vger.kernel.org> # 3.15+
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10951/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for 3.17. It contains:
- misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy updates
- MIPS ptrace updates and cleanups
- various fixes that will also go to -stable
- a number of cleanups and small non-critical fixes.
- NUMA support for the Loongson 3.
- more support for MSA
- support for MAAR
- various FP enhancements and fixes"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
MIPS: jz4740: remove unnecessary null test before debugfs_remove
MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive
MIPS: ZBOOT: implement stack protector in compressed boot phase
MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT
MIPS: Bonito64: remove a duplicate define
MIPS: Malta: initialise MAARs
MIPS: Initialise MAARs
MIPS: detect presence of MAARs
MIPS: define MAAR register accessors & bits
MIPS: mark MSA experimental
MIPS: Don't build MSA support unless it can be used
MIPS: consistently clear MSA flags when starting & copying threads
MIPS: 16 byte align MSA vector context
MIPS: disable preemption whilst initialising MSA
MIPS: ensure MSA gets disabled during boot
MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains
MIPS: fix MSA context for tasks which don't use FP first
MIPS: init upper 64b of vector registers when MSA is first used
MIPS: save/disable MSA in lose_fpu
MIPS: preserve scalar FP CSR when switching vector context
...
Jiaxun Yang
Thomas Bogendoerfer
Masahiro Yamada
Firoz Khan
Paul Burton
James Hogan
Ralf Baechle
David Howells
Matt Redfearn
Eric B Munson
Markos Chandras
Linus Torvalds
Sorin Dumitru