From: "Eric W. Biederman" <ebiederm@xmission.com>

Date: Fri, 28 May 2021 13:38:19 -0500

Subject: signal/sparc: si_trapno is only used with SIGILL ILL_ILLTRP

Git-commit: 2c9f7eaf08659fa23d25b93a446f74306b3abea8

Patch-mainline: v5.15-rc1

References: jsc#PED-1755 (dependent patch)

While reviewing the signal handlers on sparc it became clear that

si_trapno is only set to a non-zero value when sending SIGILL with

si_code ILL_ILLTRP.

Add force_sig_fault_trapno and send SIGILL ILL_ILLTRP with it.

Remove the define of __ARCH_SI_TRAPNO and remove the always zero

si_trapno parameter from send_sig_fault and force_sig_fault.

v1: https://lkml.kernel.org/r/m1eeers7q7.fsf_-_@fess.ebiederm.org

v2: https://lkml.kernel.org/r/20210505141101.11519-7-ebiederm@xmission.com

Link: https://lkml.kernel.org/r/87mtqnxx89.fsf_-_@disp2133

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Signed-off-by: Tony Jones <tonyj@suse.de>

---

 arch/sparc/include/uapi/asm/siginfo.h |  3 ---

 arch/sparc/kernel/process_64.c        |  2 +-

 arch/sparc/kernel/sys_sparc_32.c      |  2 +-

 arch/sparc/kernel/sys_sparc_64.c      |  2 +-

 arch/sparc/kernel/traps_32.c          | 22 +++++++++---------

 arch/sparc/kernel/traps_64.c          | 44 +++++++++++++++--------------------

 arch/sparc/kernel/unaligned_32.c      |  2 +-

 arch/sparc/mm/fault_32.c              |  2 +-

 arch/sparc/mm/fault_64.c              |  2 +-

 include/linux/sched/signal.h          |  1 +

 kernel/signal.c                       | 19 +++++++++++++++

 11 files changed, 56 insertions(+), 45 deletions(-)

diff --git a/arch/sparc/include/uapi/asm/siginfo.h b/arch/sparc/include/uapi/asm/siginfo.h

index 68bdde4c2a2e..0e7c27522aed 100644

--- a/arch/sparc/include/uapi/asm/siginfo.h

+++ b/arch/sparc/include/uapi/asm/siginfo.h

@@ -8,9 +8,6 @@

 #endif /* defined(__sparc__) && defined(__arch64__) */

-

-#define __ARCH_SI_TRAPNO

-

 #include <asm-generic/siginfo.h>

diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c

index d33c58a58d4f..547b06b49ce3 100644

--- a/arch/sparc/kernel/process_64.c

+++ b/arch/sparc/kernel/process_64.c

@@ -518,7 +518,7 @@ void synchronize_user_stack(void)

 static void stack_unaligned(unsigned long sp)

 {

-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp, 0);

+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp);

 }

 static const char uwfault32[] = KERN_INFO \

diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c

index be77538bc038..082a551897ed 100644

--- a/arch/sparc/kernel/sys_sparc_32.c

+++ b/arch/sparc/kernel/sys_sparc_32.c

@@ -151,7 +151,7 @@ sparc_breakpoint (struct pt_regs *regs)

 #ifdef DEBUG_SPARC_BREAKPOINT

         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);

 #endif

-	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc, 0);

+	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);

 #ifdef DEBUG_SPARC_BREAKPOINT

 	printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c

index 6b92fadb6ec7..1e9a9e016237 100644

--- a/arch/sparc/kernel/sys_sparc_64.c

+++ b/arch/sparc/kernel/sys_sparc_64.c

@@ -514,7 +514,7 @@ asmlinkage void sparc_breakpoint(struct pt_regs *regs)

 #ifdef DEBUG_SPARC_BREAKPOINT

         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);

 #endif

-	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc, 0);

+	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc);

 #ifdef DEBUG_SPARC_BREAKPOINT

 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);

 #endif

diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c

index 247a0d9683b2..5630e5a395e0 100644

--- a/arch/sparc/kernel/traps_32.c

+++ b/arch/sparc/kernel/traps_32.c

@@ -102,8 +102,8 @@ void do_hw_interrupt(struct pt_regs *regs, unsigned long type)

 	if(regs->psr & PSR_PS)

 		die_if_kernel("Kernel bad trap", regs);

-	force_sig_fault(SIGILL, ILL_ILLTRP,

-			(void __user *)regs->pc, type - 0x80);

+	force_sig_fault_trapno(SIGILL, ILL_ILLTRP,

+			       (void __user *)regs->pc, type - 0x80);

 }

 void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,

@@ -116,7 +116,7 @@ void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned lon

 	       regs->pc, *(unsigned long *)regs->pc);

 #endif

-	send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, 0, current);

+	send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, current);

 }

 void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,

@@ -124,7 +124,7 @@ void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long n

 {

 	if(psr & PSR_PS)

 		die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);

-	send_sig_fault(SIGILL, ILL_PRVOPC, (void __user *)pc, 0, current);

+	send_sig_fault(SIGILL, ILL_PRVOPC, (void __user *)pc, current);

 }

 /* XXX User may want to be allowed to do this. XXX */

@@ -145,7 +145,7 @@ void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned lon

 #endif

 	send_sig_fault(SIGBUS, BUS_ADRALN,

 		       /* FIXME: Should dig out mna address */ (void *)0,

-		       0, current);

+		       current);

 }

 static unsigned long init_fsr = 0x0UL;

@@ -291,7 +291,7 @@ void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,

 		else if (fsr & 0x01)

 			code = FPE_FLTRES;

 	}

-	send_sig_fault(SIGFPE, code, (void __user *)pc, 0, fpt);

+	send_sig_fault(SIGFPE, code, (void __user *)pc, fpt);

 #ifndef CONFIG_SMP

 	last_task_used_math = NULL;

 #endif

@@ -305,7 +305,7 @@ void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long n

 {

 	if(psr & PSR_PS)

 		die_if_kernel("Penguin overflow trap from kernel mode", regs);

-	send_sig_fault(SIGEMT, EMT_TAGOVF, (void __user *)pc, 0, current);

+	send_sig_fault(SIGEMT, EMT_TAGOVF, (void __user *)pc, current);

 }

 void handle_watchpoint(struct pt_regs *regs, unsigned long pc, unsigned long npc,

@@ -327,13 +327,13 @@ void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc

 	printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",

 	       pc, npc, psr);

 #endif

-	force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc, 0);

+	force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc);

 }

 void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,

 			unsigned long psr)

 {

-	send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, 0, current);

+	send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);

 }

 void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long npc,

@@ -343,13 +343,13 @@ void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long n

 	printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",

 	       pc, npc, psr);

 #endif

-	send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, 0, current);

+	send_sig_fault(SIGILL, ILL_COPROC, (void __user *)pc, current);

 }

 void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc,

 		       unsigned long psr)

 {

-	send_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)pc, 0, current);

+	send_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)pc, current);

 }

 #ifdef CONFIG_DEBUG_BUGVERBOSE

diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c

index a850dccd78ea..6863025ed56d 100644

--- a/arch/sparc/kernel/traps_64.c

+++ b/arch/sparc/kernel/traps_64.c

@@ -107,8 +107,8 @@ void bad_trap(struct pt_regs *regs, long lvl)

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGILL, ILL_ILLTRP,

-			(void __user *)regs->tpc, lvl);

+	force_sig_fault_trapno(SIGILL, ILL_ILLTRP,

+			       (void __user *)regs->tpc, lvl);

 }

 void bad_trap_tl1(struct pt_regs *regs, long lvl)

@@ -201,8 +201,7 @@ void spitfire_insn_access_exception(struct pt_regs *regs, unsigned long sfsr, un

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGSEGV, SEGV_MAPERR,

-			(void __user *)regs->tpc, 0);

+	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)regs->tpc);

 out:

 	exception_exit(prev_state);

 }

@@ -237,7 +236,7 @@ void sun4v_insn_access_exception(struct pt_regs *regs, unsigned long addr, unsig

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *) addr, 0);

+	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *) addr);

 }

 void sun4v_insn_access_exception_tl1(struct pt_regs *regs, unsigned long addr, unsigned long type_ctx)

@@ -321,7 +320,7 @@ void spitfire_data_access_exception(struct pt_regs *regs, unsigned long sfsr, un

 	if (is_no_fault_exception(regs))

 		return;

-	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)sfar, 0);

+	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)sfar);

 out:

 	exception_exit(prev_state);

 }

@@ -385,13 +384,13 @@ void sun4v_data_access_exception(struct pt_regs *regs, unsigned long addr, unsig

 	 */

 	switch (type) {

 	case HV_FAULT_TYPE_INV_ASI:

-		force_sig_fault(SIGILL, ILL_ILLADR, (void __user *)addr, 0);

+		force_sig_fault(SIGILL, ILL_ILLADR, (void __user *)addr);

 		break;

 	case HV_FAULT_TYPE_MCD_DIS:

-		force_sig_fault(SIGSEGV, SEGV_ACCADI, (void __user *)addr, 0);

+		force_sig_fault(SIGSEGV, SEGV_ACCADI, (void __user *)addr);

 		break;

 	default:

-		force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)addr, 0);

+		force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)addr);

 		break;

 	}

 }

@@ -568,7 +567,7 @@ static void spitfire_ue_log(unsigned long afsr, unsigned long afar, unsigned lon

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGBUS, BUS_OBJERR, (void *)0, 0);

+	force_sig_fault(SIGBUS, BUS_OBJERR, (void *)0);

 }

 void spitfire_access_error(struct pt_regs *regs, unsigned long status_encoded, unsigned long afar)

@@ -2069,8 +2068,7 @@ void do_mcd_err(struct pt_regs *regs, struct sun4v_error_entry ent)

 	/* Send SIGSEGV to the userspace process with the right signal

 	 * code

 	 */

-	force_sig_fault(SIGSEGV, SEGV_ADIDERR, (void __user *)ent.err_raddr,

-			0);

+	force_sig_fault(SIGSEGV, SEGV_ADIDERR, (void __user *)ent.err_raddr);

 }

 /* We run with %pil set to PIL_NORMAL_MAX and PSTATE_IE enabled in %pstate.

@@ -2184,7 +2182,7 @@ bool sun4v_nonresum_error_user_handled(struct pt_regs *regs,

 	}

 	if (attrs & SUN4V_ERR_ATTRS_PIO) {

 		force_sig_fault(SIGBUS, BUS_ADRERR,

-				(void __user *)sun4v_get_vaddr(regs), 0);

+				(void __user *)sun4v_get_vaddr(regs));

 		return true;

 	}

@@ -2340,8 +2338,7 @@ static void do_fpe_common(struct pt_regs *regs)

 			else if (fsr & 0x01)

 				code = FPE_FLTRES;

 		}

-		force_sig_fault(SIGFPE, code,

-				(void __user *)regs->tpc, 0);

+		force_sig_fault(SIGFPE, code, (void __user *)regs->tpc);

 	}

 }

@@ -2395,8 +2392,7 @@ void do_tof(struct pt_regs *regs)

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGEMT, EMT_TAGOVF,

-			(void __user *)regs->tpc, 0);

+	force_sig_fault(SIGEMT, EMT_TAGOVF, (void __user *)regs->tpc);

 out:

 	exception_exit(prev_state);

 }

@@ -2415,8 +2411,7 @@ void do_div0(struct pt_regs *regs)

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGFPE, FPE_INTDIV,

-			(void __user *)regs->tpc, 0);

+	force_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)regs->tpc);

 out:

 	exception_exit(prev_state);

 }

@@ -2612,7 +2607,7 @@ void do_illegal_instruction(struct pt_regs *regs)

 			}

 		}

 	}

-	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, 0);

+	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc);

 out:

 	exception_exit(prev_state);

 }

@@ -2632,7 +2627,7 @@ void mem_address_unaligned(struct pt_regs *regs, unsigned long sfar, unsigned lo

 	if (is_no_fault_exception(regs))

 		return;

-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)sfar, 0);

+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)sfar);

 out:

 	exception_exit(prev_state);

 }

@@ -2650,7 +2645,7 @@ void sun4v_do_mna(struct pt_regs *regs, unsigned long addr, unsigned long type_c

 	if (is_no_fault_exception(regs))

 		return;

-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) addr, 0);

+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) addr);

 }

 /* sun4v_mem_corrupt_detect_precise() - Handle precise exception on an ADI

@@ -2697,7 +2692,7 @@ void sun4v_mem_corrupt_detect_precise(struct pt_regs *regs, unsigned long addr,

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGSEGV, SEGV_ADIPERR, (void __user *)addr, 0);

+	force_sig_fault(SIGSEGV, SEGV_ADIPERR, (void __user *)addr);

 }

 void do_privop(struct pt_regs *regs)

@@ -2712,8 +2707,7 @@ void do_privop(struct pt_regs *regs)

 		regs->tpc &= 0xffffffff;

 		regs->tnpc &= 0xffffffff;

 	}

-	force_sig_fault(SIGILL, ILL_PRVOPC,

-			(void __user *)regs->tpc, 0);

+	force_sig_fault(SIGILL, ILL_PRVOPC, (void __user *)regs->tpc);

 out:

 	exception_exit(prev_state);

 }

diff --git a/arch/sparc/kernel/unaligned_32.c b/arch/sparc/kernel/unaligned_32.c

index ef5c5207c9ff..455f0258c745 100644

--- a/arch/sparc/kernel/unaligned_32.c

+++ b/arch/sparc/kernel/unaligned_32.c

@@ -278,5 +278,5 @@ asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)

 {

 	send_sig_fault(SIGBUS, BUS_ADRALN,

 		       (void __user *)safe_compute_effective_address(regs, insn),

-		       0, current);

+		       current);

 }

diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c

index de2031c2b2d7..fa858626b85b 100644

--- a/arch/sparc/mm/fault_32.c

+++ b/arch/sparc/mm/fault_32.c

@@ -83,7 +83,7 @@ static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs,

 		show_signal_msg(regs, sig, code,

 				addr, current);

-	force_sig_fault(sig, code, (void __user *) addr, 0);

+	force_sig_fault(sig, code, (void __user *) addr);

 }

 static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault)

diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c

index 0a6bcc85fba7..9a9652a15fed 100644

--- a/arch/sparc/mm/fault_64.c

+++ b/arch/sparc/mm/fault_64.c

@@ -176,7 +176,7 @@ static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,

 	if (unlikely(show_unhandled_signals))

 		show_signal_msg(regs, sig, code, addr, current);

-	force_sig_fault(sig, code, (void __user *) addr, 0);

+	force_sig_fault(sig, code, (void __user *) addr);

 }

 static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn)

diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h

index b9126fe06c3f..99a9ab2b169a 100644

--- a/include/linux/sched/signal.h

+++ b/include/linux/sched/signal.h

@@ -329,6 +329,7 @@ int force_sig_pkuerr(void __user *addr, u32 pkey);

 int force_sig_perf(void __user *addr, u32 type, u64 sig_data);

 int force_sig_ptrace_errno_trap(int errno, void __user *addr);

+int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno);

 extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);

 extern void force_sigsegv(int sig);

diff --git a/kernel/signal.c b/kernel/signal.c

index a3229add4455..87a374225277 100644

--- a/kernel/signal.c

+++ b/kernel/signal.c

@@ -1808,6 +1808,22 @@ 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;;

+}

+

 int kill_pgrp(struct pid *pid, int sig, int priv)

 {

 	int ret;

@@ -3243,6 +3259,9 @@ enum siginfo_layout siginfo_layout(unsigned sig, int si_code)

 #endif

 			else if ((sig == SIGTRAP) && (si_code == TRAP_PERF))

 				layout = SIL_PERF_EVENT;

+			else if (IS_ENABLED(CONFIG_SPARC) &&

+				 (sig == SIGILL) && (si_code == ILL_ILLTRP))

+				layout = SIL_FAULT_TRAPNO;

 #ifdef __ARCH_SI_TRAPNO

 			else if (layout == SIL_FAULT)

 				layout = SIL_FAULT_TRAPNO;