Merge branch 'parisc-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

torvalds · torvalds · commit c05c2ec96bb8 · 2016-03-31T07:55:14.000-05:00
Pull parisc fixes from Helge Deller:
 "Fix seccomp filter support and SIGSYS signals on compat kernel.

  Both patches are tagged for v4.5 stable kernel"

* 'parisc-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix and enable seccomp filter support
  parisc: Fix SIGSYS signals in compat case
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
@@ -30,6 +30,7 @@ config PARISC
 	select TTY # Needed for pdc_cons.c
 	select HAVE_DEBUG_STACKOVERFLOW
 	select HAVE_ARCH_AUDITSYSCALL
+	select HAVE_ARCH_SECCOMP_FILTER
 	select ARCH_NO_COHERENT_DMA_MMAP
 
 	help
diff --git a/arch/parisc/include/asm/compat.h b/arch/parisc/include/asm/compat.h
@@ -183,6 +183,13 @@ typedef struct compat_siginfo {
 			int _band;      /* POLL_IN, POLL_OUT, POLL_MSG */
 			int _fd;
 		} _sigpoll;
+
+		/* SIGSYS */
+		struct {
+			compat_uptr_t _call_addr; /* calling user insn */
+			int _syscall;	/* triggering system call number */
+			compat_uint_t _arch;	/* AUDIT_ARCH_* of syscall */
+		} _sigsys;
 	} _sifields;
 } compat_siginfo_t;
 
diff --git a/arch/parisc/include/asm/syscall.h b/arch/parisc/include/asm/syscall.h
@@ -39,6 +39,19 @@ static inline void syscall_get_arguments(struct task_struct *tsk,
 	}
 }
 
+static inline void syscall_set_return_value(struct task_struct *task,
+					    struct pt_regs *regs,
+					    int error, long val)
+{
+	regs->gr[28] = error ? error : val;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+				    struct pt_regs *regs)
+{
+	/* do nothing */
+}
+
 static inline int syscall_get_arch(void)
 {
 	int arch = AUDIT_ARCH_PARISC;
diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
@@ -270,7 +270,8 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 long do_syscall_trace_enter(struct pt_regs *regs)
 {
 	/* Do the secure computing check first. */
-	secure_computing_strict(regs->gr[20]);
+	if (secure_computing() == -1)
+		return -1;
 
 	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 	    tracehook_report_syscall_entry(regs)) {
@@ -296,7 +297,11 @@ long do_syscall_trace_enter(struct pt_regs *regs)
 			regs->gr[23] & 0xffffffff);
 
 out:
-	return regs->gr[20];
+	/*
+	 * Sign extend the syscall number to 64bit since it may have been
+	 * modified by a compat ptrace call
+	 */
+	return (int) ((u32) regs->gr[20]);
 }
 
 void do_syscall_trace_exit(struct pt_regs *regs)
diff --git a/arch/parisc/kernel/signal32.c b/arch/parisc/kernel/signal32.c
@@ -371,6 +371,11 @@ copy_siginfo_to_user32 (compat_siginfo_t __user *to, const siginfo_t *from)
 			val = (compat_int_t)from->si_int;
 			err |= __put_user(val, &to->si_int);
 			break;
+		case __SI_SYS >> 16:
+			err |= __put_user(ptr_to_compat(from->si_call_addr), &to->si_call_addr);
+			err |= __put_user(from->si_syscall, &to->si_syscall);
+			err |= __put_user(from->si_arch, &to->si_arch);
+			break;
 		}
 	}
 	return err;
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
@@ -329,6 +329,7 @@ tracesys_next:
 
 	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
 	LDREG	TI_TASK(%r1), %r1
+	LDREG   TASK_PT_GR28(%r1), %r28		/* Restore return value */
 	LDREG   TASK_PT_GR26(%r1), %r26		/* Restore the users args */
 	LDREG   TASK_PT_GR25(%r1), %r25
 	LDREG   TASK_PT_GR24(%r1), %r24
@@ -342,6 +343,7 @@ tracesys_next:
 	stw     %r21, -56(%r30)                 /* 6th argument */
 #endif
 
+	cmpib,COND(=),n -1,%r20,tracesys_exit /* seccomp may have returned -1 */
 	comiclr,>>=	__NR_Linux_syscalls, %r20, %r0
 	b,n	.Ltracesys_nosys
 

Original file line number	Diff line number	Diff line change
`@@ -39,6 +39,19 @@ static inline void syscall_get_arguments(struct task_struct *tsk,`
`39`	`39`	`}`
`40`	`40`	`}`
`41`	`41`
	`42`	`+static inline void syscall_set_return_value(struct task_struct *task,`
	`43`	`+ struct pt_regs *regs,`
	`44`	`+ int error, long val)`
	`45`	`+{`
	`46`	`+ regs->gr[28] = error ? error : val;`
	`47`	`+}`
	`48`	`+`
	`49`	`+static inline void syscall_rollback(struct task_struct *task,`
	`50`	`+ struct pt_regs *regs)`
	`51`	`+{`
	`52`	`+ /* do nothing */`
	`53`	`+}`
	`54`	`+`
`42`	`55`	`static inline int syscall_get_arch(void)`
`43`	`56`	`{`
`44`	`57`	`int arch = AUDIT_ARCH_PARISC;`
Original file line number	Diff line number	Diff line change
`@@ -371,6 +371,11 @@ copy_siginfo_to_user32 (compat_siginfo_t __user to, const siginfo_t from)`
`371`	`371`	`val = (compat_int_t)from->si_int;`
`372`	`372`	`err \|= __put_user(val, &to->si_int);`
`373`	`373`	`break;`
	`374`	`+ case __SI_SYS >> 16:`
	`375`	`+ err \|= __put_user(ptr_to_compat(from->si_call_addr), &to->si_call_addr);`
	`376`	`+ err \|= __put_user(from->si_syscall, &to->si_syscall);`
	`377`	`+ err \|= __put_user(from->si_arch, &to->si_arch);`
	`378`	`+ break;`
`374`	`379`	`}`
`375`	`380`	`}`
`376`	`381`	`return err;`