From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ziqian SUN , Heiko Carstens , Martin Schwidefsky Subject: [PATCH 4.9 73/74] s390/uprobes: implement arch_uretprobe_is_alive() Date: Fri, 27 Apr 2018 15:59:03 +0200 Message-Id: <20180427135712.969357908@linuxfoundation.org> In-Reply-To: <20180427135709.899303463@linuxfoundation.org> References: <20180427135709.899303463@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiko Carstens commit 783c3b53b9506db3e05daacfe34e0287eebb09d8 upstream. Implement s390 specific arch_uretprobe_is_alive() to avoid SIGSEGVs observed with uretprobes in combination with setjmp/longjmp. See commit 2dea1d9c38e4 ("powerpc/uprobes: Implement arch_uretprobe_is_alive()") for more details. With this implemented all test cases referenced in the above commit pass. Reported-by: Ziqian SUN Cc: # v4.3+ Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman --- arch/s390/kernel/uprobes.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/arch/s390/kernel/uprobes.c +++ b/arch/s390/kernel/uprobes.c @@ -147,6 +147,15 @@ unsigned long arch_uretprobe_hijack_retu return orig; } +bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx, + struct pt_regs *regs) +{ + if (ctx == RP_CHECK_CHAIN_CALL) + return user_stack_pointer(regs) <= ret->stack; + else + return user_stack_pointer(regs) < ret->stack; +} + /* Instruction Emulation */ static void adjust_psw_addr(psw_t *psw, unsigned long len)