From 0f2cb928a1547ae8f89e80a4b8df2c6c02ae5f96 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Tue, 13 Sep 2022 11:17:30 +0100 Subject: [PATCH] arm64: consistently pass ESR_ELx to die() Currently, bug_handler() and kasan_handler() call die() with '0' as the 'err' value, whereas die_kernel_fault() passes the ESR_ELx value. For consistency, this patch ensures we always pass the ESR_ELx value to die(). As this is only called for exceptions taken from kernel mode, there should be no user-visible change as a result of this patch. For UNDEFINED exceptions, I've had to modify do_undefinstr() and its callers to pass the ESR_ELx value. In all cases the ESR_ELx value had already been read and was available. Signed-off-by: Mark Rutland Cc: Mark Brown Cc: Alexandru Elisei Cc: Amit Daniel Kachhap Cc: James Morse Cc: Will Deacon Reviewed-by: Anshuman Khandual Reviewed-by: Mark Brown Link: https://lore.kernel.org/r/20220913101732.3925290-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/exception.h | 2 +- arch/arm64/kernel/entry-common.c | 14 +++++++------- arch/arm64/kernel/traps.c | 14 +++++++------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h index d94aecff9690..28c0275666e1 100644 --- a/arch/arm64/include/asm/exception.h +++ b/arch/arm64/include/asm/exception.h @@ -58,7 +58,7 @@ asmlinkage void call_on_irq_stack(struct pt_regs *regs, asmlinkage void asm_exit_to_user_mode(struct pt_regs *regs); void do_mem_abort(unsigned long far, unsigned long esr, struct pt_regs *regs); -void do_undefinstr(struct pt_regs *regs); +void do_undefinstr(struct pt_regs *regs, unsigned long esr); void do_bti(struct pt_regs *regs); void do_debug_exception(unsigned long addr_if_watchpoint, unsigned long esr, struct pt_regs *regs); diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index c75ca36b4a49..3dd17ef6d6d8 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -379,11 +379,11 @@ static void noinstr el1_pc(struct pt_regs *regs, unsigned long esr) exit_to_kernel_mode(regs); } -static void noinstr el1_undef(struct pt_regs *regs) +static void noinstr el1_undef(struct pt_regs *regs, unsigned long esr) { enter_from_kernel_mode(regs); local_daif_inherit(regs); - do_undefinstr(regs); + do_undefinstr(regs, esr); local_daif_mask(); exit_to_kernel_mode(regs); } @@ -425,7 +425,7 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs) break; case ESR_ELx_EC_SYS64: case ESR_ELx_EC_UNKNOWN: - el1_undef(regs); + el1_undef(regs, esr); break; case ESR_ELx_EC_BREAKPT_CUR: case ESR_ELx_EC_SOFTSTP_CUR: @@ -582,11 +582,11 @@ static void noinstr el0_sp(struct pt_regs *regs, unsigned long esr) exit_to_user_mode(regs); } -static void noinstr el0_undef(struct pt_regs *regs) +static void noinstr el0_undef(struct pt_regs *regs, unsigned long esr) { enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); - do_undefinstr(regs); + do_undefinstr(regs, esr); exit_to_user_mode(regs); } @@ -670,7 +670,7 @@ asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs) el0_pc(regs, esr); break; case ESR_ELx_EC_UNKNOWN: - el0_undef(regs); + el0_undef(regs, esr); break; case ESR_ELx_EC_BTI: el0_bti(regs); @@ -788,7 +788,7 @@ asmlinkage void noinstr el0t_32_sync_handler(struct pt_regs *regs) case ESR_ELx_EC_CP14_MR: case ESR_ELx_EC_CP14_LS: case ESR_ELx_EC_CP14_64: - el0_undef(regs); + el0_undef(regs, esr); break; case ESR_ELx_EC_CP15_32: case ESR_ELx_EC_CP15_64: diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index da8ffef6f7c5..05999cde870a 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -485,7 +485,7 @@ void arm64_notify_segfault(unsigned long addr) force_signal_inject(SIGSEGV, code, addr, 0); } -void do_undefinstr(struct pt_regs *regs) +void do_undefinstr(struct pt_regs *regs, unsigned long esr) { /* check for AArch32 breakpoint instructions */ if (!aarch32_break_handler(regs)) @@ -495,7 +495,7 @@ void do_undefinstr(struct pt_regs *regs) return; if (!user_mode(regs)) - die("Oops - Undefined instruction", regs, 0); + die("Oops - Undefined instruction", regs, esr); force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0); } @@ -760,7 +760,7 @@ void do_cp15instr(unsigned long esr, struct pt_regs *regs) hook_base = cp15_64_hooks; break; default: - do_undefinstr(regs); + do_undefinstr(regs, esr); return; } @@ -775,7 +775,7 @@ void do_cp15instr(unsigned long esr, struct pt_regs *regs) * EL0. Fall back to our usual undefined instruction handler * so that we handle these consistently. */ - do_undefinstr(regs); + do_undefinstr(regs, esr); } NOKPROBE_SYMBOL(do_cp15instr); #endif @@ -795,7 +795,7 @@ void do_sysinstr(unsigned long esr, struct pt_regs *regs) * back to our usual undefined instruction handler so that we handle * these consistently. */ - do_undefinstr(regs); + do_undefinstr(regs, esr); } NOKPROBE_SYMBOL(do_sysinstr); @@ -972,7 +972,7 @@ static int bug_handler(struct pt_regs *regs, unsigned long esr) { switch (report_bug(regs->pc, regs)) { case BUG_TRAP_TYPE_BUG: - die("Oops - BUG", regs, 0); + die("Oops - BUG", regs, esr); break; case BUG_TRAP_TYPE_WARN: @@ -1040,7 +1040,7 @@ static int kasan_handler(struct pt_regs *regs, unsigned long esr) * This is something that might be fixed at some point in the future. */ if (!recover) - die("Oops - KASAN", regs, 0); + die("Oops - KASAN", regs, esr); /* If thread survives, skip over the brk instruction and continue: */ arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);