linux/arch/mips/kernel/scall64-o32.S
Markos Chandras d218af7849 MIPS: scall: Always run the seccomp syscall filters
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>
2015-10-04 12:10:56 +02:00

581 lines
14 KiB
ArmAsm

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1995 - 2000, 2001 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2001 MIPS Technologies, Inc.
* Copyright (C) 2004 Thiemo Seufer
*
* Hairy, the userspace application uses a different argument passing
* convention than the kernel, so we have to translate things from o32
* to ABI64 calling convention. 64-bit syscalls are also processed
* here for now.
*/
#include <linux/errno.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/irqflags.h>
#include <asm/mipsregs.h>
#include <asm/regdef.h>
#include <asm/stackframe.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
#include <asm/sysmips.h>
.align 5
NESTED(handle_sys, PT_SIZE, sp)
.set noat
SAVE_SOME
TRACE_IRQS_ON_RELOAD
STI
.set at
ld t1, PT_EPC(sp) # skip syscall on return
dsubu t0, v0, __NR_O32_Linux # check syscall number
sltiu t0, t0, __NR_O32_Linux_syscalls + 1
daddiu t1, 4 # skip to next instruction
sd t1, PT_EPC(sp)
beqz t0, not_o32_scall
#if 0
SAVE_ALL
move a1, v0
PRINT("Scall %ld\n")
RESTORE_ALL
#endif
/* We don't want to stumble over broken sign extensions from
userland. O32 does never use the upper half. */
sll a0, a0, 0
sll a1, a1, 0
sll a2, a2, 0
sll a3, a3, 0
dsll t0, v0, 3 # offset into table
ld t2, (sys32_call_table - (__NR_O32_Linux * 8))(t0)
sd a3, PT_R26(sp) # save a3 for syscall restarting
/*
* More than four arguments. Try to deal with it by copying the
* stack arguments from the user stack to the kernel stack.
* This Sucks (TM).
*
* We intentionally keep the kernel stack a little below the top of
* userspace so we don't have to do a slower byte accurate check here.
*/
ld t0, PT_R29(sp) # get old user stack pointer
daddu t1, t0, 32
bltz t1, bad_stack
load_a4: lw a4, 16(t0) # argument #5 from usp
load_a5: lw a5, 20(t0) # argument #6 from usp
load_a6: lw a6, 24(t0) # argument #7 from usp
load_a7: lw a7, 28(t0) # argument #8 from usp
loads_done:
.section __ex_table,"a"
PTR load_a4, bad_stack_a4
PTR load_a5, bad_stack_a5
PTR load_a6, bad_stack_a6
PTR load_a7, bad_stack_a7
.previous
li t1, _TIF_WORK_SYSCALL_ENTRY
LONG_L t0, TI_FLAGS($28) # syscall tracing enabled?
and t0, t1, t0
bnez t0, trace_a_syscall
syscall_common:
jalr t2 # Do The Real Thing (TM)
li t0, -EMAXERRNO - 1 # error?
sltu t0, t0, v0
sd t0, PT_R7(sp) # set error flag
beqz t0, 1f
ld t1, PT_R2(sp) # syscall number
dnegu v0 # error
sd t1, PT_R0(sp) # save it for syscall restarting
1: sd v0, PT_R2(sp) # result
o32_syscall_exit:
j syscall_exit_partial
/* ------------------------------------------------------------------------ */
trace_a_syscall:
SAVE_STATIC
sd a4, PT_R8(sp) # Save argument registers
sd a5, PT_R9(sp)
sd a6, PT_R10(sp)
sd a7, PT_R11(sp) # For indirect syscalls
move s0, t2 # Save syscall pointer
move a0, sp
/*
* absolute syscall number is in v0 unless we called syscall(__NR_###)
* where the real syscall number is in a0
* note: NR_syscall is the first O32 syscall but the macro is
* only defined when compiling with -mabi=32 (CONFIG_32BIT)
* therefore __NR_O32_Linux is used (4000)
*/
.set push
.set reorder
subu t1, v0, __NR_O32_Linux
move a1, v0
bnez t1, 1f /* __NR_syscall at offset 0 */
lw a1, PT_R4(sp) /* Arg1 for __NR_syscall case */
.set pop
1: jal syscall_trace_enter
bltz v0, 1f # seccomp failed? Skip syscall
move t2, s0
RESTORE_STATIC
ld a0, PT_R4(sp) # Restore argument registers
ld a1, PT_R5(sp)
ld a2, PT_R6(sp)
ld a3, PT_R7(sp)
ld a4, PT_R8(sp)
ld a5, PT_R9(sp)
ld a6, PT_R10(sp)
ld a7, PT_R11(sp) # For indirect syscalls
j syscall_common
1: j syscall_exit
/* ------------------------------------------------------------------------ */
/*
* The stackpointer for a call with more than 4 arguments is bad.
*/
bad_stack:
li v0, EFAULT
sd v0, PT_R2(sp)
li t0, 1 # set error flag
sd t0, PT_R7(sp)
j o32_syscall_exit
bad_stack_a4:
li a4, 0
b load_a5
bad_stack_a5:
li a5, 0
b load_a6
bad_stack_a6:
li a6, 0
b load_a7
bad_stack_a7:
li a7, 0
b loads_done
not_o32_scall:
/*
* This is not an o32 compatibility syscall, pass it on
* to the 64-bit syscall handlers.
*/
#ifdef CONFIG_MIPS32_N32
j handle_sysn32
#else
j handle_sys64
#endif
END(handle_sys)
LEAF(sys32_syscall)
subu t0, a0, __NR_O32_Linux # check syscall number
sltiu v0, t0, __NR_O32_Linux_syscalls + 1
beqz t0, einval # do not recurse
dsll t1, t0, 3
beqz v0, einval
ld t2, sys32_call_table(t1) # syscall routine
sd a0, PT_R2(sp) # call routine directly on restart
move a0, a1 # shift argument registers
move a1, a2
move a2, a3
move a3, a4
move a4, a5
move a5, a6
move a6, a7
sd a0, PT_R4(sp) # ... and push back a0 - a3, some
sd a1, PT_R5(sp) # syscalls expect them there
sd a2, PT_R6(sp)
sd a3, PT_R7(sp)
sd a3, PT_R26(sp) # update a3 for syscall restarting
jr t2
/* Unreached */
einval: li v0, -ENOSYS
jr ra
END(sys32_syscall)
.align 3
.type sys32_call_table,@object
EXPORT(sys32_call_table)
PTR sys32_syscall /* 4000 */
PTR sys_exit
PTR __sys_fork
PTR sys_read
PTR sys_write
PTR compat_sys_open /* 4005 */
PTR sys_close
PTR sys_waitpid
PTR sys_creat
PTR sys_link
PTR sys_unlink /* 4010 */
PTR compat_sys_execve
PTR sys_chdir
PTR compat_sys_time
PTR sys_mknod
PTR sys_chmod /* 4015 */
PTR sys_lchown
PTR sys_ni_syscall
PTR sys_ni_syscall /* was sys_stat */
PTR sys_lseek
PTR sys_getpid /* 4020 */
PTR compat_sys_mount
PTR sys_oldumount
PTR sys_setuid
PTR sys_getuid
PTR compat_sys_stime /* 4025 */
PTR compat_sys_ptrace
PTR sys_alarm
PTR sys_ni_syscall /* was sys_fstat */
PTR sys_pause
PTR compat_sys_utime /* 4030 */
PTR sys_ni_syscall
PTR sys_ni_syscall
PTR sys_access
PTR sys_nice
PTR sys_ni_syscall /* 4035 */
PTR sys_sync
PTR sys_kill
PTR sys_rename
PTR sys_mkdir
PTR sys_rmdir /* 4040 */
PTR sys_dup
PTR sysm_pipe
PTR compat_sys_times
PTR sys_ni_syscall
PTR sys_brk /* 4045 */
PTR sys_setgid
PTR sys_getgid
PTR sys_ni_syscall /* was signal 2 */
PTR sys_geteuid
PTR sys_getegid /* 4050 */
PTR sys_acct
PTR sys_umount
PTR sys_ni_syscall
PTR compat_sys_ioctl
PTR compat_sys_fcntl /* 4055 */
PTR sys_ni_syscall
PTR sys_setpgid
PTR sys_ni_syscall
PTR sys_olduname
PTR sys_umask /* 4060 */
PTR sys_chroot
PTR compat_sys_ustat
PTR sys_dup2
PTR sys_getppid
PTR sys_getpgrp /* 4065 */
PTR sys_setsid
PTR sys_32_sigaction
PTR sys_sgetmask
PTR sys_ssetmask
PTR sys_setreuid /* 4070 */
PTR sys_setregid
PTR sys32_sigsuspend
PTR compat_sys_sigpending
PTR sys_sethostname
PTR compat_sys_setrlimit /* 4075 */
PTR compat_sys_getrlimit
PTR compat_sys_getrusage
PTR compat_sys_gettimeofday
PTR compat_sys_settimeofday
PTR sys_getgroups /* 4080 */
PTR sys_setgroups
PTR sys_ni_syscall /* old_select */
PTR sys_symlink
PTR sys_ni_syscall /* was sys_lstat */
PTR sys_readlink /* 4085 */
PTR sys_uselib
PTR sys_swapon
PTR sys_reboot
PTR compat_sys_old_readdir
PTR sys_mips_mmap /* 4090 */
PTR sys_munmap
PTR compat_sys_truncate
PTR compat_sys_ftruncate
PTR sys_fchmod
PTR sys_fchown /* 4095 */
PTR sys_getpriority
PTR sys_setpriority
PTR sys_ni_syscall
PTR compat_sys_statfs
PTR compat_sys_fstatfs /* 4100 */
PTR sys_ni_syscall /* sys_ioperm */
PTR compat_sys_socketcall
PTR sys_syslog
PTR compat_sys_setitimer
PTR compat_sys_getitimer /* 4105 */
PTR compat_sys_newstat
PTR compat_sys_newlstat
PTR compat_sys_newfstat
PTR sys_uname
PTR sys_ni_syscall /* sys_ioperm *//* 4110 */
PTR sys_vhangup
PTR sys_ni_syscall /* was sys_idle */
PTR sys_ni_syscall /* sys_vm86 */
PTR compat_sys_wait4
PTR sys_swapoff /* 4115 */
PTR compat_sys_sysinfo
PTR compat_sys_ipc
PTR sys_fsync
PTR sys32_sigreturn
PTR __sys_clone /* 4120 */
PTR sys_setdomainname
PTR sys_newuname
PTR sys_ni_syscall /* sys_modify_ldt */
PTR compat_sys_adjtimex
PTR sys_mprotect /* 4125 */
PTR compat_sys_sigprocmask
PTR sys_ni_syscall /* was creat_module */
PTR sys_init_module
PTR sys_delete_module
PTR sys_ni_syscall /* 4130, get_kernel_syms */
PTR sys_quotactl
PTR sys_getpgid
PTR sys_fchdir
PTR sys_bdflush
PTR sys_sysfs /* 4135 */
PTR sys_32_personality
PTR sys_ni_syscall /* for afs_syscall */
PTR sys_setfsuid
PTR sys_setfsgid
PTR sys_32_llseek /* 4140 */
PTR compat_sys_getdents
PTR compat_sys_select
PTR sys_flock
PTR sys_msync
PTR compat_sys_readv /* 4145 */
PTR compat_sys_writev
PTR sys_cacheflush
PTR sys_cachectl
PTR sys_sysmips
PTR sys_ni_syscall /* 4150 */
PTR sys_getsid
PTR sys_fdatasync
PTR compat_sys_sysctl
PTR sys_mlock
PTR sys_munlock /* 4155 */
PTR sys_mlockall
PTR sys_munlockall
PTR sys_sched_setparam
PTR sys_sched_getparam
PTR sys_sched_setscheduler /* 4160 */
PTR sys_sched_getscheduler
PTR sys_sched_yield
PTR sys_sched_get_priority_max
PTR sys_sched_get_priority_min
PTR compat_sys_sched_rr_get_interval /* 4165 */
PTR compat_sys_nanosleep
PTR sys_mremap
PTR sys_accept
PTR sys_bind
PTR sys_connect /* 4170 */
PTR sys_getpeername
PTR sys_getsockname
PTR compat_sys_getsockopt
PTR sys_listen
PTR compat_sys_recv /* 4175 */
PTR compat_sys_recvfrom
PTR compat_sys_recvmsg
PTR sys_send
PTR compat_sys_sendmsg
PTR sys_sendto /* 4180 */
PTR compat_sys_setsockopt
PTR sys_shutdown
PTR sys_socket
PTR sys_socketpair
PTR sys_setresuid /* 4185 */
PTR sys_getresuid
PTR sys_ni_syscall /* was query_module */
PTR sys_poll
PTR sys_ni_syscall /* was nfsservctl */
PTR sys_setresgid /* 4190 */
PTR sys_getresgid
PTR sys_prctl
PTR sys32_rt_sigreturn
PTR compat_sys_rt_sigaction
PTR compat_sys_rt_sigprocmask /* 4195 */
PTR compat_sys_rt_sigpending
PTR compat_sys_rt_sigtimedwait
PTR compat_sys_rt_sigqueueinfo
PTR compat_sys_rt_sigsuspend
PTR sys_32_pread /* 4200 */
PTR sys_32_pwrite
PTR sys_chown
PTR sys_getcwd
PTR sys_capget
PTR sys_capset /* 4205 */
PTR compat_sys_sigaltstack
PTR compat_sys_sendfile
PTR sys_ni_syscall
PTR sys_ni_syscall
PTR sys_mips_mmap2 /* 4210 */
PTR sys_32_truncate64
PTR sys_32_ftruncate64
PTR sys_newstat
PTR sys_newlstat
PTR sys_newfstat /* 4215 */
PTR sys_pivot_root
PTR sys_mincore
PTR sys_madvise
PTR sys_getdents64
PTR compat_sys_fcntl64 /* 4220 */
PTR sys_ni_syscall
PTR sys_gettid
PTR sys32_readahead
PTR sys_setxattr
PTR sys_lsetxattr /* 4225 */
PTR sys_fsetxattr
PTR sys_getxattr
PTR sys_lgetxattr
PTR sys_fgetxattr
PTR sys_listxattr /* 4230 */
PTR sys_llistxattr
PTR sys_flistxattr
PTR sys_removexattr
PTR sys_lremovexattr
PTR sys_fremovexattr /* 4235 */
PTR sys_tkill
PTR sys_sendfile64
PTR compat_sys_futex
PTR compat_sys_sched_setaffinity
PTR compat_sys_sched_getaffinity /* 4240 */
PTR compat_sys_io_setup
PTR sys_io_destroy
PTR compat_sys_io_getevents
PTR compat_sys_io_submit
PTR sys_io_cancel /* 4245 */
PTR sys_exit_group
PTR compat_sys_lookup_dcookie
PTR sys_epoll_create
PTR sys_epoll_ctl
PTR sys_epoll_wait /* 4250 */
PTR sys_remap_file_pages
PTR sys_set_tid_address
PTR sys_restart_syscall
PTR sys32_fadvise64_64
PTR compat_sys_statfs64 /* 4255 */
PTR compat_sys_fstatfs64
PTR compat_sys_timer_create
PTR compat_sys_timer_settime
PTR compat_sys_timer_gettime
PTR sys_timer_getoverrun /* 4260 */
PTR sys_timer_delete
PTR compat_sys_clock_settime
PTR compat_sys_clock_gettime
PTR compat_sys_clock_getres
PTR compat_sys_clock_nanosleep /* 4265 */
PTR sys_tgkill
PTR compat_sys_utimes
PTR compat_sys_mbind
PTR compat_sys_get_mempolicy
PTR compat_sys_set_mempolicy /* 4270 */
PTR compat_sys_mq_open
PTR sys_mq_unlink
PTR compat_sys_mq_timedsend
PTR compat_sys_mq_timedreceive
PTR compat_sys_mq_notify /* 4275 */
PTR compat_sys_mq_getsetattr
PTR sys_ni_syscall /* sys_vserver */
PTR compat_sys_waitid
PTR sys_ni_syscall /* available, was setaltroot */
PTR sys_add_key /* 4280 */
PTR sys_request_key
PTR sys_keyctl
PTR sys_set_thread_area
PTR sys_inotify_init
PTR sys_inotify_add_watch /* 4285 */
PTR sys_inotify_rm_watch
PTR compat_sys_migrate_pages
PTR compat_sys_openat
PTR sys_mkdirat
PTR sys_mknodat /* 4290 */
PTR sys_fchownat
PTR compat_sys_futimesat
PTR sys_newfstatat
PTR sys_unlinkat
PTR sys_renameat /* 4295 */
PTR sys_linkat
PTR sys_symlinkat
PTR sys_readlinkat
PTR sys_fchmodat
PTR sys_faccessat /* 4300 */
PTR compat_sys_pselect6
PTR compat_sys_ppoll
PTR sys_unshare
PTR sys_splice
PTR sys32_sync_file_range /* 4305 */
PTR sys_tee
PTR compat_sys_vmsplice
PTR compat_sys_move_pages
PTR compat_sys_set_robust_list
PTR compat_sys_get_robust_list /* 4310 */
PTR compat_sys_kexec_load
PTR sys_getcpu
PTR compat_sys_epoll_pwait
PTR sys_ioprio_set
PTR sys_ioprio_get /* 4315 */
PTR compat_sys_utimensat
PTR compat_sys_signalfd
PTR sys_ni_syscall /* was timerfd */
PTR sys_eventfd
PTR sys32_fallocate /* 4320 */
PTR sys_timerfd_create
PTR compat_sys_timerfd_gettime
PTR compat_sys_timerfd_settime
PTR compat_sys_signalfd4
PTR sys_eventfd2 /* 4325 */
PTR sys_epoll_create1
PTR sys_dup3
PTR sys_pipe2
PTR sys_inotify_init1
PTR compat_sys_preadv /* 4330 */
PTR compat_sys_pwritev
PTR compat_sys_rt_tgsigqueueinfo
PTR sys_perf_event_open
PTR sys_accept4
PTR compat_sys_recvmmsg /* 4335 */
PTR sys_fanotify_init
PTR compat_sys_fanotify_mark
PTR sys_prlimit64
PTR sys_name_to_handle_at
PTR compat_sys_open_by_handle_at /* 4340 */
PTR compat_sys_clock_adjtime
PTR sys_syncfs
PTR compat_sys_sendmmsg
PTR sys_setns
PTR compat_sys_process_vm_readv /* 4345 */
PTR compat_sys_process_vm_writev
PTR sys_kcmp
PTR sys_finit_module
PTR sys_sched_setattr
PTR sys_sched_getattr /* 4350 */
PTR sys_renameat2
PTR sys_seccomp
PTR sys_getrandom
PTR sys_memfd_create
PTR sys_bpf /* 4355 */
PTR compat_sys_execveat
PTR sys_userfaultfd
PTR sys_membarrier
.size sys32_call_table,.-sys32_call_table