1 files changed, 54 insertions, 62 deletions

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index ab2568996ddb..e07f359254c3 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -9,7 +9,7 @@
 #include <linux/signal.h>
 #include <linux/personality.h>
 #include <linux/uaccess.h>
-#include <linux/tracehook.h>
+#include <linux/resume_user_mode.h>
 #include <linux/uprobes.h>
 #include <linux/syscalls.h>
 
@@ -25,40 +25,6 @@ extern const unsigned long sigreturn_codes[17];
 
 static unsigned long signal_return_offset;
 
-#ifdef CONFIG_CRUNCH
-static int preserve_crunch_context(struct crunch_sigframe __user *frame)
-{
-	char kbuf[sizeof(*frame) + 8];
-	struct crunch_sigframe *kframe;
-
-	/* the crunch context must be 64 bit aligned */
-	kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
-	kframe->magic = CRUNCH_MAGIC;
-	kframe->size = CRUNCH_STORAGE_SIZE;
-	crunch_task_copy(current_thread_info(), &kframe->storage);
-	return __copy_to_user(frame, kframe, sizeof(*frame));
-}
-
-static int restore_crunch_context(char __user **auxp)
-{
-	struct crunch_sigframe __user *frame =
-		(struct crunch_sigframe __user *)*auxp;
-	char kbuf[sizeof(*frame) + 8];
-	struct crunch_sigframe *kframe;
-
-	/* the crunch context must be 64 bit aligned */
-	kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
-	if (__copy_from_user(kframe, frame, sizeof(*frame)))
-		return -1;
-	if (kframe->magic != CRUNCH_MAGIC ||
-	    kframe->size != CRUNCH_STORAGE_SIZE)
-		return -1;
-	*auxp += CRUNCH_STORAGE_SIZE;
-	crunch_task_restore(current_thread_info(), &kframe->storage);
-	return 0;
-}
-#endif
-
 #ifdef CONFIG_IWMMXT
 
 static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame)
@@ -205,10 +171,6 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 	err |= !valid_user_regs(regs);
 
 	aux = (char __user *) sf->uc.uc_regspace;
-#ifdef CONFIG_CRUNCH
-	if (err == 0)
-		err |= restore_crunch_context(&aux);
-#endif
 #ifdef CONFIG_IWMMXT
 	if (err == 0)
 		err |= restore_iwmmxt_context(&aux);
@@ -321,10 +283,6 @@ setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
 	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
 
 	aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
-#ifdef CONFIG_CRUNCH
-	if (err == 0)
-		err |= preserve_crunch_context(&aux->crunch);
-#endif
 #ifdef CONFIG_IWMMXT
 	if (err == 0)
 		err |= preserve_iwmmxt_context(&aux->iwmmxt);
@@ -596,7 +554,7 @@ static int do_signal(struct pt_regs *regs, int syscall)
 		switch (retval) {
 		case -ERESTART_RESTARTBLOCK:
 			restart -= 2;
-			/* Fall through */
+			fallthrough;
 		case -ERESTARTNOHAND:
 		case -ERESTARTSYS:
 		case -ERESTARTNOINTR:
@@ -655,7 +613,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
 			if (unlikely(!user_mode(regs)))
 				return 0;
 			local_irq_enable();
-			if (thread_flags & _TIF_SIGPENDING) {
+			if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) {
 				int restart = do_signal(regs, syscall);
 				if (unlikely(restart)) {
 					/*
@@ -669,13 +627,11 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
 			} else if (thread_flags & _TIF_UPROBE) {
 				uprobe_notify_resume(regs);
 			} else {
-				clear_thread_flag(TIF_NOTIFY_RESUME);
-				tracehook_notify_resume(regs);
-				rseq_handle_notify_resume(NULL, regs);
+				resume_user_mode_work(regs);
 			}
 		}
 		local_irq_disable();
-		thread_flags = current_thread_info()->flags;
+		thread_flags = read_thread_flags();
 	} while (thread_flags & _TIF_WORK_MASK);
 	return 0;
 }
@@ -694,31 +650,67 @@ struct page *get_signal_page(void)
 
 	addr = page_address(page);
 
+	/* Poison the entire page */
+	memset32(addr, __opcode_to_mem_arm(0xe7fddef1),
+		 PAGE_SIZE / sizeof(u32));
+
 	/* Give the signal return code some randomness */
-	offset = 0x200 + (get_random_int() & 0x7fc);
+	offset = 0x200 + (get_random_u16() & 0x7fc);
 	signal_return_offset = offset;
 
-	/*
-	 * Copy signal return handlers into the vector page, and
-	 * set sigreturn to be a pointer to these.
-	 */
+	/* Copy signal return handlers into the page */
 	memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes));
 
-	ptr = (unsigned long)addr + offset;
-	flush_icache_range(ptr, ptr + sizeof(sigreturn_codes));
+	/* Flush out all instructions in this page */
+	ptr = (unsigned long)addr;
+	flush_icache_range(ptr, ptr + PAGE_SIZE);
 
 	return page;
 }
 
-/* Defer to generic check */
-asmlinkage void addr_limit_check_failed(void)
-{
-	addr_limit_user_check();
-}
-
 #ifdef CONFIG_DEBUG_RSEQ
 asmlinkage void do_rseq_syscall(struct pt_regs *regs)
 {
 	rseq_syscall(regs);
 }
 #endif
+
+/*
+ * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
+ * changes likely come with new fields that should be added below.
+ */
+static_assert(NSIGILL	== 11);
+static_assert(NSIGFPE	== 15);
+static_assert(NSIGSEGV	== 9);
+static_assert(NSIGBUS	== 5);
+static_assert(NSIGTRAP	== 6);
+static_assert(NSIGCHLD	== 6);
+static_assert(NSIGSYS	== 2);
+static_assert(sizeof(siginfo_t) == 128);
+static_assert(__alignof__(siginfo_t) == 4);
+static_assert(offsetof(siginfo_t, si_signo)	== 0x00);
+static_assert(offsetof(siginfo_t, si_errno)	== 0x04);
+static_assert(offsetof(siginfo_t, si_code)	== 0x08);
+static_assert(offsetof(siginfo_t, si_pid)	== 0x0c);
+static_assert(offsetof(siginfo_t, si_uid)	== 0x10);
+static_assert(offsetof(siginfo_t, si_tid)	== 0x0c);
+static_assert(offsetof(siginfo_t, si_overrun)	== 0x10);
+static_assert(offsetof(siginfo_t, si_status)	== 0x14);
+static_assert(offsetof(siginfo_t, si_utime)	== 0x18);
+static_assert(offsetof(siginfo_t, si_stime)	== 0x1c);
+static_assert(offsetof(siginfo_t, si_value)	== 0x14);
+static_assert(offsetof(siginfo_t, si_int)	== 0x14);
+static_assert(offsetof(siginfo_t, si_ptr)	== 0x14);
+static_assert(offsetof(siginfo_t, si_addr)	== 0x0c);
+static_assert(offsetof(siginfo_t, si_addr_lsb)	== 0x10);
+static_assert(offsetof(siginfo_t, si_lower)	== 0x14);
+static_assert(offsetof(siginfo_t, si_upper)	== 0x18);
+static_assert(offsetof(siginfo_t, si_pkey)	== 0x14);
+static_assert(offsetof(siginfo_t, si_perf_data)	== 0x10);
+static_assert(offsetof(siginfo_t, si_perf_type)	== 0x14);
+static_assert(offsetof(siginfo_t, si_perf_flags) == 0x18);
+static_assert(offsetof(siginfo_t, si_band)	== 0x0c);
+static_assert(offsetof(siginfo_t, si_fd)	== 0x10);
+static_assert(offsetof(siginfo_t, si_call_addr)	== 0x0c);
+static_assert(offsetof(siginfo_t, si_syscall)	== 0x10);
+static_assert(offsetof(siginfo_t, si_arch)	== 0x14);