From patchwork Wed Mar 31 11:56:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Bogendoerfer X-Patchwork-Id: 12175355 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F260C433E1 for ; Wed, 31 Mar 2021 11:57:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 02F8761985 for ; Wed, 31 Mar 2021 11:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235347AbhCaL4h (ORCPT ); Wed, 31 Mar 2021 07:56:37 -0400 Received: from mx2.suse.de ([195.135.220.15]:51760 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235115AbhCaL4H (ORCPT ); Wed, 31 Mar 2021 07:56:07 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 5A645B1E7; Wed, 31 Mar 2021 11:56:06 +0000 (UTC) From: Thomas Bogendoerfer To: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Cc: hch@lst.de Subject: [PATCH v2 3/4] MIPS: uaccess: Remove get_fs/set_fs call sites Date: Wed, 31 Mar 2021 13:56:00 +0200 Message-Id: <20210331115603.146159-4-tsbogend@alpha.franken.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210331115603.146159-1-tsbogend@alpha.franken.de> References: <20210331115603.146159-1-tsbogend@alpha.franken.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Use new helpers to access user/kernel for functions, which are used with user/kernel pointers. Instead of dealing with get_fs/set_fs select user/kernel access via parameter. Signed-off-by: Thomas Bogendoerfer --- arch/mips/kernel/access-helper.h | 53 ++++++++ arch/mips/kernel/traps.c | 105 +++++++--------- arch/mips/kernel/unaligned.c | 199 +++++++++++-------------------- 3 files changed, 171 insertions(+), 186 deletions(-) create mode 100644 arch/mips/kernel/access-helper.h diff --git a/arch/mips/kernel/access-helper.h b/arch/mips/kernel/access-helper.h new file mode 100644 index 000000000000..04e93203f165 --- /dev/null +++ b/arch/mips/kernel/access-helper.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include + +#define __get_user_nofault(dst, src, type, err_label) \ +do { \ + int __gu_err; \ + \ + __get_user_common(*((type *)(dst)), sizeof(type), \ + (__force type *)(src)); \ + if (unlikely(__gu_err)) \ + goto err_label; \ +} while (0) + + +static inline int __get_addr(unsigned long *a, unsigned long *p, bool user) +{ + if (user) + __get_user_nofault(a, p, unsigned long, fault); + else + __get_kernel_nofault(a, p, unsigned long, fault); + + return 0; + +fault: + return -EFAULT; +} + +static inline int __get_inst16(u16 *i, u16 *p, bool user) +{ + if (user) + __get_user_nofault(i, p, u16, fault); + else + __get_kernel_nofault(i, p, u16, fault); + + return 0; + +fault: + return -EFAULT; +} + +static inline int __get_inst32(u32 *i, u32 *p, bool user) +{ + if (user) + __get_user_nofault(i, p, u32, fault); + else + __get_kernel_nofault(i, p, u32, fault); + + return 0; + +fault: + return -EFAULT; +} diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 808b8b61ded1..0b4e06303c55 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -72,6 +72,8 @@ #include +#include "access-helper.h" + extern void check_wait(void); extern asmlinkage void rollback_handle_int(void); extern asmlinkage void handle_int(void); @@ -108,7 +110,8 @@ void (*board_bind_eic_interrupt)(int irq, int regset); void (*board_ebase_setup)(void); void(*board_cache_error_setup)(void); -static void show_raw_backtrace(unsigned long reg29, const char *loglvl) +static void show_raw_backtrace(unsigned long reg29, const char *loglvl, + bool user) { unsigned long *sp = (unsigned long *)(reg29 & ~3); unsigned long addr; @@ -118,9 +121,7 @@ static void show_raw_backtrace(unsigned long reg29, const char *loglvl) printk("%s\n", loglvl); #endif while (!kstack_end(sp)) { - unsigned long __user *p = - (unsigned long __user *)(unsigned long)sp++; - if (__get_user(addr, p)) { + if (__get_addr(&addr, sp++, user)) { printk("%s (Bad stack address)", loglvl); break; } @@ -141,7 +142,7 @@ __setup("raw_show_trace", set_raw_show_trace); #endif static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, - const char *loglvl) + const char *loglvl, bool user) { unsigned long sp = regs->regs[29]; unsigned long ra = regs->regs[31]; @@ -151,7 +152,7 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, task = current; if (raw_show_trace || user_mode(regs) || !__kernel_text_address(pc)) { - show_raw_backtrace(sp, loglvl); + show_raw_backtrace(sp, loglvl, user); return; } printk("%sCall Trace:\n", loglvl); @@ -167,12 +168,12 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, * with at least a bit of error checking ... */ static void show_stacktrace(struct task_struct *task, - const struct pt_regs *regs, const char *loglvl) + const struct pt_regs *regs, const char *loglvl, bool user) { const int field = 2 * sizeof(unsigned long); - long stackdata; + unsigned long stackdata; int i; - unsigned long __user *sp = (unsigned long __user *)regs->regs[29]; + unsigned long *sp = (unsigned long *)regs->regs[29]; printk("%sStack :", loglvl); i = 0; @@ -186,7 +187,7 @@ static void show_stacktrace(struct task_struct *task, break; } - if (__get_user(stackdata, sp++)) { + if (__get_addr(&stackdata, sp++, user)) { pr_cont(" (Bad stack address)"); break; } @@ -195,13 +196,12 @@ static void show_stacktrace(struct task_struct *task, i++; } pr_cont("\n"); - show_backtrace(task, regs, loglvl); + show_backtrace(task, regs, loglvl, user); } void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl) { struct pt_regs regs; - mm_segment_t old_fs = get_fs(); regs.cp0_status = KSU_KERNEL; if (sp) { @@ -217,33 +217,41 @@ void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl) prepare_frametrace(®s); } } - /* - * show_stack() deals exclusively with kernel mode, so be sure to access - * the stack in the kernel (not user) address space. - */ - set_fs(KERNEL_DS); - show_stacktrace(task, ®s, loglvl); - set_fs(old_fs); + show_stacktrace(task, ®s, loglvl, false); } -static void show_code(unsigned int __user *pc) +static void show_code(void *pc, bool user) { long i; - unsigned short __user *pc16 = NULL; + unsigned short *pc16 = NULL; printk("Code:"); if ((unsigned long)pc & 1) - pc16 = (unsigned short __user *)((unsigned long)pc & ~1); + pc16 = (u16 *)((unsigned long)pc & ~1); + for(i = -3 ; i < 6 ; i++) { - unsigned int insn; - if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) { - pr_cont(" (Bad address in epc)\n"); - break; + if (pc16) { + u16 insn16; + + if (__get_inst16(&insn16, pc16 + i, user)) + goto bad_address; + + pr_cont("%c%04x%c", (i?' ':'<'), insn16, (i?' ':'>')); + } else { + u32 insn32; + + if (__get_inst32(&insn32, (u32 *)pc + i, user)) + goto bad_address; + + pr_cont("%c%08x%c", (i?' ':'<'), insn32, (i?' ':'>')); } - pr_cont("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>')); } pr_cont("\n"); + return; + +bad_address: + pr_cont(" (Bad address in epc)\n\n"); } static void __show_regs(const struct pt_regs *regs) @@ -356,7 +364,6 @@ void show_regs(struct pt_regs *regs) void show_registers(struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); - mm_segment_t old_fs = get_fs(); __show_regs(regs); print_modules(); @@ -371,13 +378,9 @@ void show_registers(struct pt_regs *regs) printk("*HwTLS: %0*lx\n", field, tls); } - if (!user_mode(regs)) - /* Necessary for getting the correct stack content */ - set_fs(KERNEL_DS); - show_stacktrace(current, regs, KERN_DEFAULT); - show_code((unsigned int __user *) regs->cp0_epc); + show_stacktrace(current, regs, KERN_DEFAULT, user_mode(regs)); + show_code((void *)regs->cp0_epc, user_mode(regs)); printk("\n"); - set_fs(old_fs); } static DEFINE_RAW_SPINLOCK(die_lock); @@ -1022,18 +1025,14 @@ asmlinkage void do_bp(struct pt_regs *regs) unsigned long epc = msk_isa16_mode(exception_epc(regs)); unsigned int opcode, bcode; enum ctx_state prev_state; - mm_segment_t seg; - - seg = get_fs(); - if (!user_mode(regs)) - set_fs(KERNEL_DS); + bool user = user_mode(regs); prev_state = exception_enter(); current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; if (get_isa16_mode(regs->cp0_epc)) { u16 instr[2]; - if (__get_user(instr[0], (u16 __user *)epc)) + if (__get_inst16(&instr[0], (u16 *)epc, user)) goto out_sigsegv; if (!cpu_has_mmips) { @@ -1044,13 +1043,13 @@ asmlinkage void do_bp(struct pt_regs *regs) bcode = instr[0] & 0xf; } else { /* 32-bit microMIPS BREAK */ - if (__get_user(instr[1], (u16 __user *)(epc + 2))) + if (__get_inst16(&instr[1], (u16 *)(epc + 2), user)) goto out_sigsegv; opcode = (instr[0] << 16) | instr[1]; bcode = (opcode >> 6) & ((1 << 20) - 1); } } else { - if (__get_user(opcode, (unsigned int __user *)epc)) + if (__get_inst32(&opcode, (u32 *)epc, user)) goto out_sigsegv; bcode = (opcode >> 6) & ((1 << 20) - 1); } @@ -1100,7 +1099,6 @@ asmlinkage void do_bp(struct pt_regs *regs) do_trap_or_bp(regs, bcode, TRAP_BRKPT, "Break"); out: - set_fs(seg); exception_exit(prev_state); return; @@ -1114,25 +1112,21 @@ asmlinkage void do_tr(struct pt_regs *regs) u32 opcode, tcode = 0; enum ctx_state prev_state; u16 instr[2]; - mm_segment_t seg; + bool user = user_mode(regs); unsigned long epc = msk_isa16_mode(exception_epc(regs)); - seg = get_fs(); - if (!user_mode(regs)) - set_fs(KERNEL_DS); - prev_state = exception_enter(); current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; if (get_isa16_mode(regs->cp0_epc)) { - if (__get_user(instr[0], (u16 __user *)(epc + 0)) || - __get_user(instr[1], (u16 __user *)(epc + 2))) + if (__get_inst16(&instr[0], (u16 *)(epc + 0), user) || + __get_inst16(&instr[1], (u16 *)(epc + 2), user)) goto out_sigsegv; opcode = (instr[0] << 16) | instr[1]; /* Immediate versions don't provide a code. */ if (!(opcode & OPCODE)) tcode = (opcode >> 12) & ((1 << 4) - 1); } else { - if (__get_user(opcode, (u32 __user *)epc)) + if (__get_inst32(&opcode, (u32 *)epc, user)) goto out_sigsegv; /* Immediate versions don't provide a code. */ if (!(opcode & OPCODE)) @@ -1142,7 +1136,6 @@ asmlinkage void do_tr(struct pt_regs *regs) do_trap_or_bp(regs, tcode, 0, "Trap"); out: - set_fs(seg); exception_exit(prev_state); return; @@ -1591,7 +1584,6 @@ asmlinkage void do_mcheck(struct pt_regs *regs) { int multi_match = regs->cp0_status & ST0_TS; enum ctx_state prev_state; - mm_segment_t old_fs = get_fs(); prev_state = exception_enter(); show_regs(regs); @@ -1602,12 +1594,7 @@ asmlinkage void do_mcheck(struct pt_regs *regs) dump_tlb_all(); } - if (!user_mode(regs)) - set_fs(KERNEL_DS); - - show_code((unsigned int __user *) regs->cp0_epc); - - set_fs(old_fs); + show_code((void *)regs->cp0_epc, user_mode(regs)); /* * Some chips may have other causes of machine check (e.g. SB1 diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c index 126a5f3f4e4c..1f3b20a8c377 100644 --- a/arch/mips/kernel/unaligned.c +++ b/arch/mips/kernel/unaligned.c @@ -93,6 +93,8 @@ #include #include +#include "access-helper.h" + enum { UNALIGNED_ACTION_QUIET, UNALIGNED_ACTION_SIGNAL, @@ -112,9 +114,8 @@ static void emulate_load_store_insn(struct pt_regs *regs, unsigned long origpc, orig31, value; union mips_instruction insn; unsigned int res; -#ifdef CONFIG_EVA - mm_segment_t seg; -#endif + bool user = user_mode(regs); + origpc = (unsigned long)pc; orig31 = regs->regs[31]; @@ -123,7 +124,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, /* * This load never faults. */ - __get_user(insn.word, pc); + __get_inst32(&insn.word, pc, user); switch (insn.i_format.opcode) { /* @@ -163,7 +164,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, if (insn.dsp_format.func == lx_op) { switch (insn.dsp_format.op) { case lwx_op: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadW(addr, value, res); if (res) @@ -172,7 +173,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, regs->regs[insn.dsp_format.rd] = value; break; case lhx_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; LoadHW(addr, value, res); if (res) @@ -191,93 +192,66 @@ static void emulate_load_store_insn(struct pt_regs *regs, * memory, so we need to "switch" the address limit to * user space, so that address check can work properly. */ - seg = force_uaccess_begin(); switch (insn.spec3_format.func) { case lhe_op: - if (!access_ok(addr, 2)) { - force_uaccess_end(seg); + if (!access_ok(addr, 2)) goto sigbus; - } LoadHWE(addr, value, res); - if (res) { - force_uaccess_end(seg); + if (res) goto fault; - } compute_return_epc(regs); regs->regs[insn.spec3_format.rt] = value; break; case lwe_op: - if (!access_ok(addr, 4)) { - force_uaccess_end(seg); + if (!access_ok(addr, 4)) goto sigbus; - } LoadWE(addr, value, res); - if (res) { - force_uaccess_end(seg); + if (res) goto fault; - } compute_return_epc(regs); regs->regs[insn.spec3_format.rt] = value; break; case lhue_op: - if (!access_ok(addr, 2)) { - force_uaccess_end(seg); + if (!access_ok(addr, 2)) goto sigbus; - } LoadHWUE(addr, value, res); - if (res) { - force_uaccess_end(seg); + if (res) goto fault; - } compute_return_epc(regs); regs->regs[insn.spec3_format.rt] = value; break; case she_op: - if (!access_ok(addr, 2)) { - force_uaccess_end(seg); + if (!access_ok(addr, 2)) goto sigbus; - } compute_return_epc(regs); value = regs->regs[insn.spec3_format.rt]; StoreHWE(addr, value, res); - if (res) { - force_uaccess_end(seg); + if (res) goto fault; - } break; case swe_op: - if (!access_ok(addr, 4)) { - force_uaccess_end(seg); + if (!access_ok(addr, 4)) goto sigbus; - } compute_return_epc(regs); value = regs->regs[insn.spec3_format.rt]; StoreWE(addr, value, res); - if (res) { - force_uaccess_end(seg); + if (res) goto fault; - } break; default: - force_uaccess_end(seg); goto sigill; } - force_uaccess_end(seg); } #endif break; case lh_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; - if (IS_ENABLED(CONFIG_EVA)) { - if (uaccess_kernel()) - LoadHW(addr, value, res); - else - LoadHWE(addr, value, res); - } else { + if (IS_ENABLED(CONFIG_EVA) && user) + LoadHWE(addr, value, res); + else LoadHW(addr, value, res); - } if (res) goto fault; @@ -286,17 +260,13 @@ static void emulate_load_store_insn(struct pt_regs *regs, break; case lw_op: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; - if (IS_ENABLED(CONFIG_EVA)) { - if (uaccess_kernel()) - LoadW(addr, value, res); - else - LoadWE(addr, value, res); - } else { + if (IS_ENABLED(CONFIG_EVA) && user) + LoadWE(addr, value, res); + else LoadW(addr, value, res); - } if (res) goto fault; @@ -305,17 +275,13 @@ static void emulate_load_store_insn(struct pt_regs *regs, break; case lhu_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; - if (IS_ENABLED(CONFIG_EVA)) { - if (uaccess_kernel()) - LoadHWU(addr, value, res); - else - LoadHWUE(addr, value, res); - } else { + if (IS_ENABLED(CONFIG_EVA) && user) + LoadHWUE(addr, value, res); + else LoadHWU(addr, value, res); - } if (res) goto fault; @@ -332,7 +298,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadWU(addr, value, res); @@ -355,7 +321,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; LoadDW(addr, value, res); @@ -370,40 +336,32 @@ static void emulate_load_store_insn(struct pt_regs *regs, goto sigill; case sh_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; compute_return_epc(regs); value = regs->regs[insn.i_format.rt]; - if (IS_ENABLED(CONFIG_EVA)) { - if (uaccess_kernel()) - StoreHW(addr, value, res); - else - StoreHWE(addr, value, res); - } else { + if (IS_ENABLED(CONFIG_EVA) && user) + StoreHWE(addr, value, res); + else StoreHW(addr, value, res); - } if (res) goto fault; break; case sw_op: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; compute_return_epc(regs); value = regs->regs[insn.i_format.rt]; - if (IS_ENABLED(CONFIG_EVA)) { - if (uaccess_kernel()) - StoreW(addr, value, res); - else - StoreWE(addr, value, res); - } else { + if (IS_ENABLED(CONFIG_EVA) && user) + StoreWE(addr, value, res); + else StoreW(addr, value, res); - } if (res) goto fault; @@ -418,7 +376,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; compute_return_epc(regs); @@ -626,6 +584,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, unsigned long origpc, contpc; union mips_instruction insn; struct mm_decoded_insn mminsn; + bool user = user_mode(regs); origpc = regs->cp0_epc; orig31 = regs->regs[31]; @@ -689,7 +648,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if (reg == 31) goto sigbus; - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; LoadW(addr, value, res); @@ -708,7 +667,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if (reg == 31) goto sigbus; - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; value = regs->regs[reg]; @@ -728,7 +687,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if (reg == 31) goto sigbus; - if (!access_ok(addr, 16)) + if (user && !access_ok(addr, 16)) goto sigbus; LoadDW(addr, value, res); @@ -751,7 +710,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if (reg == 31) goto sigbus; - if (!access_ok(addr, 16)) + if (user && !access_ok(addr, 16)) goto sigbus; value = regs->regs[reg]; @@ -774,10 +733,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if ((rvar > 9) || !reg) goto sigill; if (reg & 0x10) { - if (!access_ok(addr, 4 * (rvar + 1))) + if (user && !access_ok(addr, 4 * (rvar + 1))) goto sigbus; } else { - if (!access_ok(addr, 4 * rvar)) + if (user && !access_ok(addr, 4 * rvar)) goto sigbus; } if (rvar == 9) @@ -810,10 +769,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if ((rvar > 9) || !reg) goto sigill; if (reg & 0x10) { - if (!access_ok(addr, 4 * (rvar + 1))) + if (user && !access_ok(addr, 4 * (rvar + 1))) goto sigbus; } else { - if (!access_ok(addr, 4 * rvar)) + if (user && !access_ok(addr, 4 * rvar)) goto sigbus; } if (rvar == 9) @@ -847,10 +806,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if ((rvar > 9) || !reg) goto sigill; if (reg & 0x10) { - if (!access_ok(addr, 8 * (rvar + 1))) + if (user && !access_ok(addr, 8 * (rvar + 1))) goto sigbus; } else { - if (!access_ok(addr, 8 * rvar)) + if (user && !access_ok(addr, 8 * rvar)) goto sigbus; } if (rvar == 9) @@ -888,10 +847,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, if ((rvar > 9) || !reg) goto sigill; if (reg & 0x10) { - if (!access_ok(addr, 8 * (rvar + 1))) + if (user && !access_ok(addr, 8 * (rvar + 1))) goto sigbus; } else { - if (!access_ok(addr, 8 * rvar)) + if (user && !access_ok(addr, 8 * rvar)) goto sigbus; } if (rvar == 9) @@ -1010,7 +969,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, case mm_lwm16_op: reg = insn.mm16_m_format.rlist; rvar = reg + 1; - if (!access_ok(addr, 4 * rvar)) + if (user && !access_ok(addr, 4 * rvar)) goto sigbus; for (i = 16; rvar; rvar--, i++) { @@ -1030,7 +989,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, case mm_swm16_op: reg = insn.mm16_m_format.rlist; rvar = reg + 1; - if (!access_ok(addr, 4 * rvar)) + if (user && !access_ok(addr, 4 * rvar)) goto sigbus; for (i = 16; rvar; rvar--, i++) { @@ -1084,7 +1043,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, } loadHW: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; LoadHW(addr, value, res); @@ -1094,7 +1053,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, goto success; loadHWU: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; LoadHWU(addr, value, res); @@ -1104,7 +1063,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, goto success; loadW: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadW(addr, value, res); @@ -1122,7 +1081,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadWU(addr, value, res); @@ -1144,7 +1103,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; LoadDW(addr, value, res); @@ -1158,7 +1117,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, goto sigill; storeHW: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; value = regs->regs[reg]; @@ -1168,7 +1127,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, goto success; storeW: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; value = regs->regs[reg]; @@ -1186,7 +1145,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs, * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; value = regs->regs[reg]; @@ -1243,6 +1202,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) union mips16e_instruction mips16inst, oldinst; unsigned int opcode; int extended = 0; + bool user = user_mode(regs); origpc = regs->cp0_epc; orig31 = regs->regs[31]; @@ -1344,7 +1304,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) goto sigbus; case MIPS16e_lh_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; LoadHW(addr, value, res); @@ -1355,7 +1315,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) break; case MIPS16e_lhu_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; LoadHWU(addr, value, res); @@ -1368,7 +1328,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) case MIPS16e_lw_op: case MIPS16e_lwpc_op: case MIPS16e_lwsp_op: - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadW(addr, value, res); @@ -1387,7 +1347,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; LoadWU(addr, value, res); @@ -1411,7 +1371,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; LoadDW(addr, value, res); @@ -1426,7 +1386,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) goto sigill; case MIPS16e_sh_op: - if (!access_ok(addr, 2)) + if (user && !access_ok(addr, 2)) goto sigbus; MIPS16e_compute_return_epc(regs, &oldinst); @@ -1439,7 +1399,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) case MIPS16e_sw_op: case MIPS16e_swsp_op: case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */ - if (!access_ok(addr, 4)) + if (user && !access_ok(addr, 4)) goto sigbus; MIPS16e_compute_return_epc(regs, &oldinst); @@ -1459,7 +1419,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) * would blow up, so for now we don't handle unaligned 64-bit * instructions on 32-bit kernels. */ - if (!access_ok(addr, 8)) + if (user && !access_ok(addr, 8)) goto sigbus; MIPS16e_compute_return_epc(regs, &oldinst); @@ -1516,7 +1476,6 @@ asmlinkage void do_ade(struct pt_regs *regs) { enum ctx_state prev_state; unsigned int __user *pc; - mm_segment_t seg; prev_state = exception_enter(); perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, @@ -1551,24 +1510,14 @@ asmlinkage void do_ade(struct pt_regs *regs) show_registers(regs); if (cpu_has_mmips) { - seg = get_fs(); - if (!user_mode(regs)) - set_fs(KERNEL_DS); emulate_load_store_microMIPS(regs, (void __user *)regs->cp0_badvaddr); - set_fs(seg); - return; } if (cpu_has_mips16) { - seg = get_fs(); - if (!user_mode(regs)) - set_fs(KERNEL_DS); emulate_load_store_MIPS16e(regs, (void __user *)regs->cp0_badvaddr); - set_fs(seg); - return; } @@ -1579,11 +1528,7 @@ asmlinkage void do_ade(struct pt_regs *regs) show_registers(regs); pc = (unsigned int __user *)exception_epc(regs); - seg = get_fs(); - if (!user_mode(regs)) - set_fs(KERNEL_DS); emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc); - set_fs(seg); return;