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-rw-r--r--arch/parisc/Kconfig16
-rw-r--r--arch/parisc/hpux/sys_hpux.c2
-rw-r--r--arch/parisc/include/asm/seccomp.h16
-rw-r--r--arch/parisc/include/asm/thread_info.h5
-rw-r--r--arch/parisc/include/uapi/asm/unistd.h5
-rw-r--r--arch/parisc/kernel/ptrace.c6
-rw-r--r--arch/parisc/kernel/syscall.S233
-rw-r--r--arch/parisc/kernel/syscall_table.S3
8 files changed, 279 insertions, 7 deletions
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 6e75e2030927..1554a6f2a5bb 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -321,6 +321,22 @@ source "fs/Kconfig"
source "arch/parisc/Kconfig.debug"
+config SECCOMP
+ def_bool y
+ prompt "Enable seccomp to safely compute untrusted bytecode"
+ ---help---
+ This kernel feature is useful for number crunching applications
+ that may need to compute untrusted bytecode during their
+ execution. By using pipes or other transports made available to
+ the process as file descriptors supporting the read/write
+ syscalls, it's possible to isolate those applications in
+ their own address space using seccomp. Once seccomp is
+ enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
+ and the task is only allowed to execute a few safe syscalls
+ defined by each seccomp mode.
+
+ If unsure, say Y. Only embedded should say N here.
+
source "security/Kconfig"
source "crypto/Kconfig"
diff --git a/arch/parisc/hpux/sys_hpux.c b/arch/parisc/hpux/sys_hpux.c
index d9dc6cd3b7d2..e5c4da035810 100644
--- a/arch/parisc/hpux/sys_hpux.c
+++ b/arch/parisc/hpux/sys_hpux.c
@@ -456,7 +456,7 @@ int hpux_sysfs(int opcode, unsigned long arg1, unsigned long arg2)
}
/* String could be altered by userspace after strlen_user() */
- fsname[len] = '\0';
+ fsname[len - 1] = '\0';
printk(KERN_DEBUG "that is '%s' as (char *)\n", fsname);
if ( !strcmp(fsname, "hfs") ) {
diff --git a/arch/parisc/include/asm/seccomp.h b/arch/parisc/include/asm/seccomp.h
new file mode 100644
index 000000000000..015f7887aa29
--- /dev/null
+++ b/arch/parisc/include/asm/seccomp.h
@@ -0,0 +1,16 @@
+#ifndef _ASM_PARISC_SECCOMP_H
+#define _ASM_PARISC_SECCOMP_H
+
+#include <linux/unistd.h>
+
+#define __NR_seccomp_read __NR_read
+#define __NR_seccomp_write __NR_write
+#define __NR_seccomp_exit __NR_exit
+#define __NR_seccomp_sigreturn __NR_rt_sigreturn
+
+#define __NR_seccomp_read_32 __NR_read
+#define __NR_seccomp_write_32 __NR_write
+#define __NR_seccomp_exit_32 __NR_exit
+#define __NR_seccomp_sigreturn_32 __NR_rt_sigreturn
+
+#endif /* _ASM_PARISC_SECCOMP_H */
diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index 4b9b10ce1f9d..a84611835549 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -60,6 +60,7 @@ struct thread_info {
#define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
#define TIF_SINGLESTEP 9 /* single stepping? */
#define TIF_BLOCKSTEP 10 /* branch stepping? */
+#define TIF_SECCOMP 11 /* secure computing */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
@@ -70,11 +71,13 @@ struct thread_info {
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
#define _TIF_BLOCKSTEP (1 << TIF_BLOCKSTEP)
+#define _TIF_SECCOMP (1 << TIF_SECCOMP)
#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | \
_TIF_NEED_RESCHED)
#define _TIF_SYSCALL_TRACE_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
- _TIF_BLOCKSTEP | _TIF_SYSCALL_AUDIT)
+ _TIF_BLOCKSTEP | _TIF_SYSCALL_AUDIT | \
+ _TIF_SECCOMP)
#ifdef CONFIG_64BIT
# ifdef CONFIG_COMPAT
diff --git a/arch/parisc/include/uapi/asm/unistd.h b/arch/parisc/include/uapi/asm/unistd.h
index 47e0e21d2272..8667f18be238 100644
--- a/arch/parisc/include/uapi/asm/unistd.h
+++ b/arch/parisc/include/uapi/asm/unistd.h
@@ -830,8 +830,11 @@
#define __NR_sched_getattr (__NR_Linux + 335)
#define __NR_utimes (__NR_Linux + 336)
#define __NR_renameat2 (__NR_Linux + 337)
+#define __NR_seccomp (__NR_Linux + 338)
+#define __NR_getrandom (__NR_Linux + 339)
+#define __NR_memfd_create (__NR_Linux + 340)
-#define __NR_Linux_syscalls (__NR_renameat2 + 1)
+#define __NR_Linux_syscalls (__NR_memfd_create + 1)
#define __IGNORE_select /* newselect */
diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
index e842ee233db4..3bab72462ab5 100644
--- a/arch/parisc/kernel/ptrace.c
+++ b/arch/parisc/kernel/ptrace.c
@@ -270,6 +270,12 @@ long do_syscall_trace_enter(struct pt_regs *regs)
{
long ret = 0;
+ /* Do the secure computing check first. */
+ if (secure_computing(regs->gr[20])) {
+ /* seccomp failures shouldn't expose any additional code. */
+ return -1;
+ }
+
if (test_thread_flag(TIF_SYSCALL_TRACE) &&
tracehook_report_syscall_entry(regs))
ret = -1L;
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index 838786011037..7ef22e3387e0 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -74,7 +74,7 @@ ENTRY(linux_gateway_page)
/* ADDRESS 0xb0 to 0xb8, lws uses two insns for entry */
/* Light-weight-syscall entry must always be located at 0xb0 */
/* WARNING: Keep this number updated with table size changes */
-#define __NR_lws_entries (2)
+#define __NR_lws_entries (3)
lws_entry:
gate lws_start, %r0 /* increase privilege */
@@ -502,7 +502,7 @@ lws_exit:
/***************************************************
- Implementing CAS as an atomic operation:
+ Implementing 32bit CAS as an atomic operation:
%r26 - Address to examine
%r25 - Old value to check (old)
@@ -659,6 +659,230 @@ cas_action:
ASM_EXCEPTIONTABLE_ENTRY(2b-linux_gateway_page, 3b-linux_gateway_page)
+ /***************************************************
+ New CAS implementation which uses pointers and variable size
+ information. The value pointed by old and new MUST NOT change
+ while performing CAS. The lock only protect the value at %r26.
+
+ %r26 - Address to examine
+ %r25 - Pointer to the value to check (old)
+ %r24 - Pointer to the value to set (new)
+ %r23 - Size of the variable (0/1/2/3 for 8/16/32/64 bit)
+ %r28 - Return non-zero on failure
+ %r21 - Kernel error code
+
+ %r21 has the following meanings:
+
+ EAGAIN - CAS is busy, ldcw failed, try again.
+ EFAULT - Read or write failed.
+
+ Scratch: r20, r22, r28, r29, r1, fr4 (32bit for 64bit CAS only)
+
+ ****************************************************/
+
+ /* ELF32 Process entry path */
+lws_compare_and_swap_2:
+#ifdef CONFIG_64BIT
+ /* Clip the input registers */
+ depdi 0, 31, 32, %r26
+ depdi 0, 31, 32, %r25
+ depdi 0, 31, 32, %r24
+ depdi 0, 31, 32, %r23
+#endif
+
+ /* Check the validity of the size pointer */
+ subi,>>= 4, %r23, %r0
+ b,n lws_exit_nosys
+
+ /* Jump to the functions which will load the old and new values into
+ registers depending on the their size */
+ shlw %r23, 2, %r29
+ blr %r29, %r0
+ nop
+
+ /* 8bit load */
+4: ldb 0(%sr3,%r25), %r25
+ b cas2_lock_start
+5: ldb 0(%sr3,%r24), %r24
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* 16bit load */
+6: ldh 0(%sr3,%r25), %r25
+ b cas2_lock_start
+7: ldh 0(%sr3,%r24), %r24
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* 32bit load */
+8: ldw 0(%sr3,%r25), %r25
+ b cas2_lock_start
+9: ldw 0(%sr3,%r24), %r24
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* 64bit load */
+#ifdef CONFIG_64BIT
+10: ldd 0(%sr3,%r25), %r25
+11: ldd 0(%sr3,%r24), %r24
+#else
+ /* Load new value into r22/r23 - high/low */
+10: ldw 0(%sr3,%r25), %r22
+11: ldw 4(%sr3,%r25), %r23
+ /* Load new value into fr4 for atomic store later */
+12: flddx 0(%sr3,%r24), %fr4
+#endif
+
+cas2_lock_start:
+ /* Load start of lock table */
+ ldil L%lws_lock_start, %r20
+ ldo R%lws_lock_start(%r20), %r28
+
+ /* Extract four bits from r26 and hash lock (Bits 4-7) */
+ extru %r26, 27, 4, %r20
+
+ /* Find lock to use, the hash is either one of 0 to
+ 15, multiplied by 16 (keep it 16-byte aligned)
+ and add to the lock table offset. */
+ shlw %r20, 4, %r20
+ add %r20, %r28, %r20
+
+ rsm PSW_SM_I, %r0 /* Disable interrupts */
+ /* COW breaks can cause contention on UP systems */
+ LDCW 0(%sr2,%r20), %r28 /* Try to acquire the lock */
+ cmpb,<>,n %r0, %r28, cas2_action /* Did we get it? */
+cas2_wouldblock:
+ ldo 2(%r0), %r28 /* 2nd case */
+ ssm PSW_SM_I, %r0
+ b lws_exit /* Contended... */
+ ldo -EAGAIN(%r0), %r21 /* Spin in userspace */
+
+ /*
+ prev = *addr;
+ if ( prev == old )
+ *addr = new;
+ return prev;
+ */
+
+ /* NOTES:
+ This all works becuse intr_do_signal
+ and schedule both check the return iasq
+ and see that we are on the kernel page
+ so this process is never scheduled off
+ or is ever sent any signal of any sort,
+ thus it is wholly atomic from usrspaces
+ perspective
+ */
+cas2_action:
+ /* Jump to the correct function */
+ blr %r29, %r0
+ /* Set %r28 as non-zero for now */
+ ldo 1(%r0),%r28
+
+ /* 8bit CAS */
+13: ldb,ma 0(%sr3,%r26), %r29
+ sub,= %r29, %r25, %r0
+ b,n cas2_end
+14: stb,ma %r24, 0(%sr3,%r26)
+ b cas2_end
+ copy %r0, %r28
+ nop
+ nop
+
+ /* 16bit CAS */
+15: ldh,ma 0(%sr3,%r26), %r29
+ sub,= %r29, %r25, %r0
+ b,n cas2_end
+16: sth,ma %r24, 0(%sr3,%r26)
+ b cas2_end
+ copy %r0, %r28
+ nop
+ nop
+
+ /* 32bit CAS */
+17: ldw,ma 0(%sr3,%r26), %r29
+ sub,= %r29, %r25, %r0
+ b,n cas2_end
+18: stw,ma %r24, 0(%sr3,%r26)
+ b cas2_end
+ copy %r0, %r28
+ nop
+ nop
+
+ /* 64bit CAS */
+#ifdef CONFIG_64BIT
+19: ldd,ma 0(%sr3,%r26), %r29
+ sub,= %r29, %r25, %r0
+ b,n cas2_end
+20: std,ma %r24, 0(%sr3,%r26)
+ copy %r0, %r28
+#else
+ /* Compare first word */
+19: ldw,ma 0(%sr3,%r26), %r29
+ sub,= %r29, %r22, %r0
+ b,n cas2_end
+ /* Compare second word */
+20: ldw,ma 4(%sr3,%r26), %r29
+ sub,= %r29, %r23, %r0
+ b,n cas2_end
+ /* Perform the store */
+21: fstdx %fr4, 0(%sr3,%r26)
+ copy %r0, %r28
+#endif
+
+cas2_end:
+ /* Free lock */
+ stw,ma %r20, 0(%sr2,%r20)
+ /* Enable interrupts */
+ ssm PSW_SM_I, %r0
+ /* Return to userspace, set no error */
+ b lws_exit
+ copy %r0, %r21
+
+22:
+ /* Error occurred on load or store */
+ /* Free lock */
+ stw %r20, 0(%sr2,%r20)
+ ssm PSW_SM_I, %r0
+ ldo 1(%r0),%r28
+ b lws_exit
+ ldo -EFAULT(%r0),%r21 /* set errno */
+ nop
+ nop
+ nop
+
+ /* Exception table entries, for the load and store, return EFAULT.
+ Each of the entries must be relocated. */
+ ASM_EXCEPTIONTABLE_ENTRY(4b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(5b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(6b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(7b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(8b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(9b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(10b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(11b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(13b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(14b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(15b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(16b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(17b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(18b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(19b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(20b-linux_gateway_page, 22b-linux_gateway_page)
+#ifndef CONFIG_64BIT
+ ASM_EXCEPTIONTABLE_ENTRY(12b-linux_gateway_page, 22b-linux_gateway_page)
+ ASM_EXCEPTIONTABLE_ENTRY(21b-linux_gateway_page, 22b-linux_gateway_page)
+#endif
+
/* Make sure nothing else is placed on this page */
.align PAGE_SIZE
END(linux_gateway_page)
@@ -675,8 +899,9 @@ ENTRY(end_linux_gateway_page)
/* Light-weight-syscall table */
/* Start of lws table. */
ENTRY(lws_table)
- LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic compare and swap */
- LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic compare and swap */
+ LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic 32bit CAS */
+ LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic 32bit CAS */
+ LWS_ENTRY(compare_and_swap_2) /* 2 - ELF32 Atomic 64bit CAS */
END(lws_table)
/* End of lws table */
diff --git a/arch/parisc/kernel/syscall_table.S b/arch/parisc/kernel/syscall_table.S
index 84c5d3a58fa1..b563d9c8268b 100644
--- a/arch/parisc/kernel/syscall_table.S
+++ b/arch/parisc/kernel/syscall_table.S
@@ -433,6 +433,9 @@
ENTRY_SAME(sched_getattr) /* 335 */
ENTRY_COMP(utimes)
ENTRY_SAME(renameat2)
+ ENTRY_SAME(seccomp)
+ ENTRY_SAME(getrandom)
+ ENTRY_SAME(memfd_create) /* 340 */
/* Nothing yet */