From: Omar Sandoval Date: Fri, 1 Aug 2014 17:14:06 +0000 (+0100) Subject: ARM: 8124/1: don't enter kgdb when userspace executes a kgdb break instruction X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=6bf755db4d5e7ccea61fb17727a183b9bd8945b1;p=deliverable%2Flinux.git ARM: 8124/1: don't enter kgdb when userspace executes a kgdb break instruction The kgdb breakpoint hooks (kgdb_brk_fn and kgdb_compiled_brk_fn) should only be entered when a kgdb break instruction is executed from the kernel. Otherwise, if kgdb is enabled, a userspace program can cause the kernel to drop into the debugger by executing either KGDB_BREAKINST or KGDB_COMPILED_BREAK. Acked-by: Will Deacon Signed-off-by: Omar Sandoval Signed-off-by: Russell King --- diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c index 778c2f7024ff..a74b53c1b7df 100644 --- a/arch/arm/kernel/kgdb.c +++ b/arch/arm/kernel/kgdb.c @@ -160,12 +160,16 @@ static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int instr) static struct undef_hook kgdb_brkpt_hook = { .instr_mask = 0xffffffff, .instr_val = KGDB_BREAKINST, + .cpsr_mask = MODE_MASK, + .cpsr_val = SVC_MODE, .fn = kgdb_brk_fn }; static struct undef_hook kgdb_compiled_brkpt_hook = { .instr_mask = 0xffffffff, .instr_val = KGDB_COMPILED_BREAK, + .cpsr_mask = MODE_MASK, + .cpsr_val = SVC_MODE, .fn = kgdb_compiled_brk_fn };