Merge 3.17-rc5 into tty-next

We want those fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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 */