From 65d47fd4a37cbd60d0737cdae09edf1d208364d7 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 19 Jul 2017 14:49:33 +1000 Subject: [PATCH] powerpc/mm: Simplify returns from __do_page_fault Now that we moved the exception state handling to a wrapper, we can just directly return rather than "goto bail" Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman --- arch/powerpc/mm/fault.c | 39 ++++++++++++++++----------------------- 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 2f825ae..e8d6acc 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -233,39 +233,36 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, if (error_code & ICSWX_DSI_UCT) { rc = acop_handle_fault(regs, address, error_code); if (rc) - goto bail; + return rc; } #endif /* CONFIG_PPC_ICSWX */ if (notify_page_fault(regs)) - goto bail; + return 0; if (unlikely(page_fault_is_bad(error_code))) { - if (is_user) + if (is_user) { _exception(SIGBUS, regs, BUS_OBJERR, address); - else - rc = SIGBUS; - goto bail; + return 0; + } + return SIGBUS; } /* * The kernel should never take an execute fault nor should it * take a page fault to a kernel address. */ - if (!is_user && (is_exec || (address >= TASK_SIZE))) { - rc = SIGSEGV; - goto bail; - } + if (!is_user && (is_exec || (address >= TASK_SIZE))) + return SIGSEGV; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); if (faulthandler_disabled() || mm == NULL) { - if (!is_user) { - rc = SIGSEGV; - goto bail; - } + if (!is_user) + return SIGSEGV; + /* faulthandler_disabled() in user mode is really bad, as is current->mm == NULL. */ printk(KERN_EMERG "Page fault in user mode with " @@ -454,9 +451,8 @@ good_area: goto bad_area_nosemaphore; rc = mm_fault_error(regs, address, fault); if (rc >= MM_FAULT_RETURN) - goto bail; - else - rc = 0; + return rc; + rc = 0; } /* @@ -483,7 +479,7 @@ good_area: regs, address); } - goto bail; + return rc; bad_area: up_read(&mm->mmap_sem); @@ -492,7 +488,7 @@ bad_area_nosemaphore: /* User mode accesses cause a SIGSEGV */ if (is_user) { _exception(SIGSEGV, regs, code, address); - goto bail; + return 0; } if (is_exec && (error_code & DSISR_PROTFAULT)) @@ -500,10 +496,7 @@ bad_area_nosemaphore: " page (%lx) - exploit attempt? (uid: %d)\n", address, from_kuid(&init_user_ns, current_uid())); - rc = SIGSEGV; - -bail: - return rc; + return SIGSEGV; } NOKPROBE_SYMBOL(__do_page_fault); -- 2.7.4