1 files changed, 86 insertions, 23 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index a3229add4455..952741f6d0f9 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -54,6 +54,7 @@
 #include <asm/unistd.h>
 #include <asm/siginfo.h>
 #include <asm/cacheflush.h>
+#include <asm/syscall.h>	/* for syscall_get_* */
 
 /*
  * SLAB caches for signal bits.
@@ -1213,7 +1214,7 @@ static inline bool has_si_pid_and_uid(struct kernel_siginfo *info)
 	case SIL_FAULT_MCEERR:
 	case SIL_FAULT_BNDERR:
 	case SIL_FAULT_PKUERR:
-	case SIL_PERF_EVENT:
+	case SIL_FAULT_PERF_EVENT:
 	case SIL_SYS:
 		ret = false;
 		break;
@@ -1322,7 +1323,7 @@ int do_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p
  * that is why we also clear SIGNAL_UNKILLABLE.
  */
 static int
-force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
+force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t, bool sigdfl)
 {
 	unsigned long int flags;
 	int ret, blocked, ignored;
@@ -1333,7 +1334,7 @@ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
 	action = &t->sighand->action[sig-1];
 	ignored = action->sa.sa_handler == SIG_IGN;
 	blocked = sigismember(&t->blocked, sig);
-	if (blocked || ignored) {
+	if (blocked || ignored || sigdfl) {
 		action->sa.sa_handler = SIG_DFL;
 		if (blocked) {
 			sigdelset(&t->blocked, sig);
@@ -1354,7 +1355,7 @@ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
 
 int force_sig_info(struct kernel_siginfo *info)
 {
-	return force_sig_info_to_task(info, current);
+	return force_sig_info_to_task(info, current, false);
 }
 
 /*
@@ -1413,6 +1414,21 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
 	return sighand;
 }
 
+#ifdef CONFIG_LOCKDEP
+void lockdep_assert_task_sighand_held(struct task_struct *task)
+{
+	struct sighand_struct *sighand;
+
+	rcu_read_lock();
+	sighand = rcu_dereference(task->sighand);
+	if (sighand)
+		lockdep_assert_held(&sighand->siglock);
+	else
+		WARN_ON_ONCE(1);
+	rcu_read_unlock();
+}
+#endif
+
 /*
  * send signal info to all the members of a group
  */
@@ -1666,7 +1682,6 @@ void force_sigsegv(int sig)
 }
 
 int force_sig_fault_to_task(int sig, int code, void __user *addr
-	___ARCH_SI_TRAPNO(int trapno)
 	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
 	, struct task_struct *t)
 {
@@ -1677,28 +1692,22 @@ int force_sig_fault_to_task(int sig, int code, void __user *addr
 	info.si_errno = 0;
 	info.si_code  = code;
 	info.si_addr  = addr;
-#ifdef __ARCH_SI_TRAPNO
-	info.si_trapno = trapno;
-#endif
 #ifdef __ia64__
 	info.si_imm = imm;
 	info.si_flags = flags;
 	info.si_isr = isr;
 #endif
-	return force_sig_info_to_task(&info, t);
+	return force_sig_info_to_task(&info, t, false);
 }
 
 int force_sig_fault(int sig, int code, void __user *addr
-	___ARCH_SI_TRAPNO(int trapno)
 	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr))
 {
 	return force_sig_fault_to_task(sig, code, addr
-				       ___ARCH_SI_TRAPNO(trapno)
 				       ___ARCH_SI_IA64(imm, flags, isr), current);
 }
 
 int send_sig_fault(int sig, int code, void __user *addr
-	___ARCH_SI_TRAPNO(int trapno)
 	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
 	, struct task_struct *t)
 {
@@ -1709,9 +1718,6 @@ int send_sig_fault(int sig, int code, void __user *addr
 	info.si_errno = 0;
 	info.si_code  = code;
 	info.si_addr  = addr;
-#ifdef __ARCH_SI_TRAPNO
-	info.si_trapno = trapno;
-#endif
 #ifdef __ia64__
 	info.si_imm = imm;
 	info.si_flags = flags;
@@ -1793,6 +1799,27 @@ int force_sig_perf(void __user *addr, u32 type, u64 sig_data)
 	return force_sig_info(&info);
 }
 
+/**
+ * force_sig_seccomp - signals the task to allow in-process syscall emulation
+ * @syscall: syscall number to send to userland
+ * @reason: filter-supplied reason code to send to userland (via si_errno)
+ *
+ * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info.
+ */
+int force_sig_seccomp(int syscall, int reason, bool force_coredump)
+{
+	struct kernel_siginfo info;
+
+	clear_siginfo(&info);
+	info.si_signo = SIGSYS;
+	info.si_code = SYS_SECCOMP;
+	info.si_call_addr = (void __user *)KSTK_EIP(current);
+	info.si_errno = reason;
+	info.si_arch = syscall_get_arch(current);
+	info.si_syscall = syscall;
+	return force_sig_info_to_task(&info, current, force_coredump);
+}
+
 /* For the crazy architectures that include trap information in
  * the errno field, instead of an actual errno value.
  */
@@ -1808,6 +1835,39 @@ int force_sig_ptrace_errno_trap(int errno, void __user *addr)
 	return force_sig_info(&info);
 }
 
+/* For the rare architectures that include trap information using
+ * si_trapno.
+ */
+int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno)
+{
+	struct kernel_siginfo info;
+
+	clear_siginfo(&info);
+	info.si_signo = sig;
+	info.si_errno = 0;
+	info.si_code  = code;
+	info.si_addr  = addr;
+	info.si_trapno = trapno;
+	return force_sig_info(&info);
+}
+
+/* For the rare architectures that include trap information using
+ * si_trapno.
+ */
+int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno,
+			  struct task_struct *t)
+{
+	struct kernel_siginfo info;
+
+	clear_siginfo(&info);
+	info.si_signo = sig;
+	info.si_errno = 0;
+	info.si_code  = code;
+	info.si_addr  = addr;
+	info.si_trapno = trapno;
+	return send_sig_info(info.si_signo, &info, t);
+}
+
 int kill_pgrp(struct pid *pid, int sig, int priv)
 {
 	int ret;
@@ -2557,7 +2617,7 @@ static void hide_si_addr_tag_bits(struct ksignal *ksig)
 	case SIL_FAULT_MCEERR:
 	case SIL_FAULT_BNDERR:
 	case SIL_FAULT_PKUERR:
-	case SIL_PERF_EVENT:
+	case SIL_FAULT_PERF_EVENT:
 		ksig->info.si_addr = arch_untagged_si_addr(
 			ksig->info.si_addr, ksig->sig, ksig->info.si_code);
 		break;
@@ -3242,11 +3302,14 @@ enum siginfo_layout siginfo_layout(unsigned sig, int si_code)
 				layout = SIL_FAULT_PKUERR;
 #endif
 			else if ((sig == SIGTRAP) && (si_code == TRAP_PERF))
-				layout = SIL_PERF_EVENT;
-#ifdef __ARCH_SI_TRAPNO
-			else if (layout == SIL_FAULT)
+				layout = SIL_FAULT_PERF_EVENT;
+			else if (IS_ENABLED(CONFIG_SPARC) &&
+				 (sig == SIGILL) && (si_code == ILL_ILLTRP))
+				layout = SIL_FAULT_TRAPNO;
+			else if (IS_ENABLED(CONFIG_ALPHA) &&
+				 ((sig == SIGFPE) ||
+				  ((sig == SIGTRAP) && (si_code == TRAP_UNK))))
 				layout = SIL_FAULT_TRAPNO;
-#endif
 		}
 		else if (si_code <= NSIGPOLL)
 			layout = SIL_POLL;
@@ -3368,7 +3431,7 @@ void copy_siginfo_to_external32(struct compat_siginfo *to,
 		to->si_addr = ptr_to_compat(from->si_addr);
 		to->si_pkey = from->si_pkey;
 		break;
-	case SIL_PERF_EVENT:
+	case SIL_FAULT_PERF_EVENT:
 		to->si_addr = ptr_to_compat(from->si_addr);
 		to->si_perf_data = from->si_perf_data;
 		to->si_perf_type = from->si_perf_type;
@@ -3445,7 +3508,7 @@ static int post_copy_siginfo_from_user32(kernel_siginfo_t *to,
 		to->si_addr = compat_ptr(from->si_addr);
 		to->si_pkey = from->si_pkey;
 		break;
-	case SIL_PERF_EVENT:
+	case SIL_FAULT_PERF_EVENT:
 		to->si_addr = compat_ptr(from->si_addr);
 		to->si_perf_data = from->si_perf_data;
 		to->si_perf_type = from->si_perf_type;
@@ -4663,7 +4726,7 @@ void __init signals_init(void)
 {
 	siginfo_buildtime_checks();
 
-	sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC);
+	sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC | SLAB_ACCOUNT);
 }
 
 #ifdef CONFIG_KGDB_KDB