From fb610f2a2006322bebeb30408fefce6a01df09ea Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 26 Feb 2019 15:37:09 +0000 Subject: [PATCH] arm64: debug: Remove redundant user_mode(regs) checks from debug handlers Now that the debug hook dispatching code takes the triggering exception level into account, there's no need for the hooks themselves to poke around with user_mode(regs). Reviewed-by: Mark Rutland Signed-off-by: Will Deacon --- arch/arm64/kernel/kgdb.c | 8 +------- arch/arm64/kernel/probes/kprobes.c | 6 ------ arch/arm64/kernel/probes/uprobes.c | 12 ++++-------- arch/arm64/kernel/traps.c | 6 ------ 4 files changed, 5 insertions(+), 27 deletions(-) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index 4c01f299aeb2..30853d5b7859 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -244,9 +244,6 @@ int kgdb_arch_handle_exception(int exception_vector, int signo, static int kgdb_brk_fn(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs)) - return DBG_HOOK_ERROR; - kgdb_handle_exception(1, SIGTRAP, 0, regs); return DBG_HOOK_HANDLED; } @@ -254,9 +251,6 @@ NOKPROBE_SYMBOL(kgdb_brk_fn) static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs)) - return DBG_HOOK_ERROR; - compiled_break = 1; kgdb_handle_exception(1, SIGTRAP, 0, regs); @@ -266,7 +260,7 @@ NOKPROBE_SYMBOL(kgdb_compiled_brk_fn); static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs) || !kgdb_single_step) + if (!kgdb_single_step) return DBG_HOOK_ERROR; kgdb_handle_exception(1, SIGTRAP, 0, regs); diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index baf97f47aec0..000f32d1a756 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -445,9 +445,6 @@ kprobe_single_step_handler(struct pt_regs *regs, unsigned int esr) struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); int retval; - if (user_mode(regs)) - return DBG_HOOK_ERROR; - /* return error if this is not our step */ retval = kprobe_ss_hit(kcb, instruction_pointer(regs)); @@ -468,9 +465,6 @@ static struct step_hook kprobes_step_hook = { static int __kprobes kprobe_breakpoint_handler(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs)) - return DBG_HOOK_ERROR; - kprobe_handler(regs); return DBG_HOOK_HANDLED; } diff --git a/arch/arm64/kernel/probes/uprobes.c b/arch/arm64/kernel/probes/uprobes.c index 7d6ea88796a6..f37ab9567676 100644 --- a/arch/arm64/kernel/probes/uprobes.c +++ b/arch/arm64/kernel/probes/uprobes.c @@ -171,7 +171,7 @@ int arch_uprobe_exception_notify(struct notifier_block *self, static int uprobe_breakpoint_handler(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs) && uprobe_pre_sstep_notifier(regs)) + if (uprobe_pre_sstep_notifier(regs)) return DBG_HOOK_HANDLED; return DBG_HOOK_ERROR; @@ -182,13 +182,9 @@ static int uprobe_single_step_handler(struct pt_regs *regs, { struct uprobe_task *utask = current->utask; - if (user_mode(regs)) { - WARN_ON(utask && - (instruction_pointer(regs) != utask->xol_vaddr + 4)); - - if (uprobe_post_sstep_notifier(regs)) - return DBG_HOOK_HANDLED; - } + WARN_ON(utask && (instruction_pointer(regs) != utask->xol_vaddr + 4)); + if (uprobe_post_sstep_notifier(regs)) + return DBG_HOOK_HANDLED; return DBG_HOOK_ERROR; } diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 85fdc3d7c556..091379744d2f 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -947,9 +947,6 @@ int is_valid_bugaddr(unsigned long addr) static int bug_handler(struct pt_regs *regs, unsigned int esr) { - if (user_mode(regs)) - return DBG_HOOK_ERROR; - switch (report_bug(regs->pc, regs)) { case BUG_TRAP_TYPE_BUG: die("Oops - BUG", regs, 0); @@ -988,9 +985,6 @@ static int kasan_handler(struct pt_regs *regs, unsigned int esr) u64 addr = regs->regs[0]; u64 pc = regs->pc; - if (user_mode(regs)) - return DBG_HOOK_ERROR; - kasan_report(addr, size, write, pc); /* -- 2.30.2