From 53d07e21854de064d9625853b8303357482b25b1 Mon Sep 17 00:00:00 2001 From: Pratyush Anand Date: Wed, 2 Nov 2016 14:40:44 +0530 Subject: [PATCH] arm64: Handle TRAP_BRKPT for user mode as well uprobe is registered at break_hook with a unique ESR code. So, when a TRAP_BRKPT occurs, call_break_hook checks if it was for uprobe. If not, then send a SIGTRAP to user. Signed-off-by: Pratyush Anand Signed-off-by: Catalin Marinas --- arch/arm64/kernel/debug-monitors.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index a8f8de012250..605df76f0a06 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -306,16 +306,20 @@ NOKPROBE_SYMBOL(call_break_hook); static int brk_handler(unsigned long addr, unsigned int esr, struct pt_regs *regs) { - if (user_mode(regs)) { - send_user_sigtrap(TRAP_BRKPT); - } + bool handler_found = false; + #ifdef CONFIG_KPROBES - else if ((esr & BRK64_ESR_MASK) == BRK64_ESR_KPROBES) { - if (kprobe_breakpoint_handler(regs, esr) != DBG_HOOK_HANDLED) - return -EFAULT; + if ((esr & BRK64_ESR_MASK) == BRK64_ESR_KPROBES) { + if (kprobe_breakpoint_handler(regs, esr) == DBG_HOOK_HANDLED) + handler_found = true; } #endif - else if (call_break_hook(regs, esr) != DBG_HOOK_HANDLED) { + if (!handler_found && call_break_hook(regs, esr) == DBG_HOOK_HANDLED) + handler_found = true; + + if (!handler_found && user_mode(regs)) { + send_user_sigtrap(TRAP_BRKPT); + } else if (!handler_found) { pr_warn("Unexpected kernel BRK exception at EL1\n"); return -EFAULT; } -- 2.39.5