From 56037369ad379224ca2f7d9e1f51add157edd55a Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Mon, 29 Mar 2010 06:59:16 +0100 Subject: [PATCH] --- yaml --- r: 189413 b: refs/heads/master c: 782a0fd16723bfc0e765d789e82853d5dc424e76 h: refs/heads/master i: 189411: 25984360051fad637ec8d57125e52484d7503978 v: v3 --- [refs] | 2 +- trunk/arch/arm/kernel/kprobes.c | 10 +++++++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/[refs] b/[refs] index 76361e9e440b..58fdb398a889 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: 367d6acceaacff1adc44f121543effb9c060e575 +refs/heads/master: 782a0fd16723bfc0e765d789e82853d5dc424e76 diff --git a/trunk/arch/arm/kernel/kprobes.c b/trunk/arch/arm/kernel/kprobes.c index 60c62c377fa9..610e0f561c32 100644 --- a/trunk/arch/arm/kernel/kprobes.c +++ b/trunk/arch/arm/kernel/kprobes.c @@ -393,6 +393,14 @@ void __kprobes jprobe_return(void) /* * Setup an empty pt_regs. Fill SP and PC fields as * they're needed by longjmp_break_handler. + * + * We allocate some slack between the original SP and start of + * our fabricated regs. To be precise we want to have worst case + * covered which is STMFD with all 16 regs so we allocate 2 * + * sizeof(struct_pt_regs)). + * + * This is to prevent any simulated instruction from writing + * over the regs when they are accessing the stack. */ "sub sp, %0, %1 \n\t" "ldr r0, ="__stringify(JPROBE_MAGIC_ADDR)"\n\t" @@ -410,7 +418,7 @@ void __kprobes jprobe_return(void) "ldmia sp, {r0 - pc} \n\t" : : "r" (kcb->jprobe_saved_regs.ARM_sp), - "I" (sizeof(struct pt_regs)), + "I" (sizeof(struct pt_regs) * 2), "J" (offsetof(struct pt_regs, ARM_sp)), "J" (offsetof(struct pt_regs, ARM_pc)), "J" (offsetof(struct pt_regs, ARM_cpsr))