Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/kernel/kprobes/Makefile b/arch/x86/kernel/kprobes/Makefile
index 0d33169..8a75343 100644
--- a/arch/x86/kernel/kprobes/Makefile
+++ b/arch/x86/kernel/kprobes/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
#
# Makefile for kernel probes
#
diff --git a/arch/x86/kernel/kprobes/common.h b/arch/x86/kernel/kprobes/common.h
index 2b949f4..7d3a2e2 100644
--- a/arch/x86/kernel/kprobes/common.h
+++ b/arch/x86/kernel/kprobes/common.h
@@ -5,15 +5,10 @@
/* Kprobes and Optprobes common header */
#include <asm/asm.h>
-
-#ifdef CONFIG_FRAME_POINTER
-# define SAVE_RBP_STRING " push %" _ASM_BP "\n" \
- " mov %" _ASM_SP ", %" _ASM_BP "\n"
-#else
-# define SAVE_RBP_STRING " push %" _ASM_BP "\n"
-#endif
+#include <asm/frame.h>
#ifdef CONFIG_X86_64
+
#define SAVE_REGS_STRING \
/* Skip cs, ip, orig_ax. */ \
" subq $24, %rsp\n" \
@@ -27,11 +22,13 @@
" pushq %r10\n" \
" pushq %r11\n" \
" pushq %rbx\n" \
- SAVE_RBP_STRING \
+ " pushq %rbp\n" \
" pushq %r12\n" \
" pushq %r13\n" \
" pushq %r14\n" \
- " pushq %r15\n"
+ " pushq %r15\n" \
+ ENCODE_FRAME_POINTER
+
#define RESTORE_REGS_STRING \
" popq %r15\n" \
" popq %r14\n" \
@@ -51,19 +48,22 @@
/* Skip orig_ax, ip, cs */ \
" addq $24, %rsp\n"
#else
+
#define SAVE_REGS_STRING \
/* Skip cs, ip, orig_ax and gs. */ \
- " subl $16, %esp\n" \
+ " subl $4*4, %esp\n" \
" pushl %fs\n" \
" pushl %es\n" \
" pushl %ds\n" \
" pushl %eax\n" \
- SAVE_RBP_STRING \
+ " pushl %ebp\n" \
" pushl %edi\n" \
" pushl %esi\n" \
" pushl %edx\n" \
" pushl %ecx\n" \
- " pushl %ebx\n"
+ " pushl %ebx\n" \
+ ENCODE_FRAME_POINTER
+
#define RESTORE_REGS_STRING \
" popl %ebx\n" \
" popl %ecx\n" \
@@ -72,8 +72,8 @@
" popl %edi\n" \
" popl %ebp\n" \
" popl %eax\n" \
- /* Skip ds, es, fs, gs, orig_ax, and ip. Note: don't pop cs here*/\
- " addl $24, %esp\n"
+ /* Skip ds, es, fs, gs, orig_ax, ip, and cs. */\
+ " addl $7*4, %esp\n"
#endif
/* Ensure if the instruction can be boostable */
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index b0d1e81..43fc13c 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Kernel Probes (KProbes)
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
* Copyright (C) IBM Corporation, 2002, 2004
*
* 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
@@ -69,7 +56,7 @@
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
-#define stack_addr(regs) ((unsigned long *)kernel_stack_pointer(regs))
+#define stack_addr(regs) ((unsigned long *)regs->sp)
#define W(row, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, ba, bb, bc, bd, be, bf)\
(((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
@@ -431,8 +418,21 @@
void *page;
page = module_alloc(PAGE_SIZE);
- if (page)
- set_memory_ro((unsigned long)page & PAGE_MASK, 1);
+ if (!page)
+ return NULL;
+
+ set_vm_flush_reset_perms(page);
+ /*
+ * First make the page read-only, and only then make it executable to
+ * prevent it from being W+X in between.
+ */
+ set_memory_ro((unsigned long)page, 1);
+
+ /*
+ * TODO: Once additional kernel code protection mechanisms are set, ensure
+ * that the page was not maliciously altered and it is still zeroed.
+ */
+ set_memory_x((unsigned long)page, 1);
return page;
}
@@ -440,8 +440,6 @@
/* Recover page to RW mode before releasing it */
void free_insn_page(void *page)
{
- set_memory_nx((unsigned long)page & PAGE_MASK, 1);
- set_memory_rw((unsigned long)page & PAGE_MASK, 1);
module_memfree(page);
}
@@ -569,6 +567,7 @@
unsigned long *sara = stack_addr(regs);
ri->ret_addr = (kprobe_opcode_t *) *sara;
+ ri->fp = sara;
/* Replace the return addr with trampoline addr */
*sara = (unsigned long) &kretprobe_trampoline;
@@ -581,7 +580,7 @@
if (setup_detour_execution(p, regs, reenter))
return;
-#if !defined(CONFIG_PREEMPT)
+#if !defined(CONFIG_PREEMPTION)
if (p->ainsn.boostable && !p->post_handler) {
/* Boost up -- we can execute copied instructions directly */
if (!reenter)
@@ -715,32 +714,31 @@
* calls trampoline_handler() runs, which calls the kretprobe's handler.
*/
asm(
+ ".text\n"
".global kretprobe_trampoline\n"
".type kretprobe_trampoline, @function\n"
"kretprobe_trampoline:\n"
-#ifdef CONFIG_X86_64
/* We don't bother saving the ss register */
+#ifdef CONFIG_X86_64
" pushq %rsp\n"
" pushfq\n"
SAVE_REGS_STRING
" movq %rsp, %rdi\n"
" call trampoline_handler\n"
/* Replace saved sp with true return address. */
- " movq %rax, 152(%rsp)\n"
+ " movq %rax, 19*8(%rsp)\n"
RESTORE_REGS_STRING
" popfq\n"
#else
- " pushf\n"
+ " pushl %esp\n"
+ " pushfl\n"
SAVE_REGS_STRING
" movl %esp, %eax\n"
" call trampoline_handler\n"
- /* Move flags to cs */
- " movl 56(%esp), %edx\n"
- " movl %edx, 52(%esp)\n"
- /* Replace saved flags with true return address. */
- " movl %eax, 56(%esp)\n"
+ /* Replace saved sp with true return address. */
+ " movl %eax, 15*4(%esp)\n"
RESTORE_REGS_STRING
- " popf\n"
+ " popfl\n"
#endif
" ret\n"
".size kretprobe_trampoline, .-kretprobe_trampoline\n"
@@ -748,27 +746,46 @@
NOKPROBE_SYMBOL(kretprobe_trampoline);
STACK_FRAME_NON_STANDARD(kretprobe_trampoline);
+static struct kprobe kretprobe_kprobe = {
+ .addr = (void *)kretprobe_trampoline,
+};
+
/*
* Called from kretprobe_trampoline
*/
-__visible __used void *trampoline_handler(struct pt_regs *regs)
+__used __visible void *trampoline_handler(struct pt_regs *regs)
{
+ struct kprobe_ctlblk *kcb;
struct kretprobe_instance *ri = NULL;
struct hlist_head *head, empty_rp;
struct hlist_node *tmp;
unsigned long flags, orig_ret_address = 0;
unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline;
kprobe_opcode_t *correct_ret_addr = NULL;
+ void *frame_pointer;
+ bool skipped = false;
+
+ preempt_disable();
+
+ /*
+ * Set a dummy kprobe for avoiding kretprobe recursion.
+ * Since kretprobe never run in kprobe handler, kprobe must not
+ * be running at this point.
+ */
+ kcb = get_kprobe_ctlblk();
+ __this_cpu_write(current_kprobe, &kretprobe_kprobe);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
INIT_HLIST_HEAD(&empty_rp);
kretprobe_hash_lock(current, &head, &flags);
/* fixup registers */
-#ifdef CONFIG_X86_64
regs->cs = __KERNEL_CS;
-#else
- regs->cs = __KERNEL_CS | get_kernel_rpl();
+#ifdef CONFIG_X86_32
+ regs->cs |= get_kernel_rpl();
regs->gs = 0;
#endif
+ /* We use pt_regs->sp for return address holder. */
+ frame_pointer = ®s->sp;
regs->ip = trampoline_address;
regs->orig_ax = ~0UL;
@@ -789,8 +806,25 @@
if (ri->task != current)
/* another task is sharing our hash bucket */
continue;
+ /*
+ * Return probes must be pushed on this hash list correct
+ * order (same as return order) so that it can be popped
+ * correctly. However, if we find it is pushed it incorrect
+ * order, this means we find a function which should not be
+ * probed, because the wrong order entry is pushed on the
+ * path of processing other kretprobe itself.
+ */
+ if (ri->fp != frame_pointer) {
+ if (!skipped)
+ pr_warn("kretprobe is stacked incorrectly. Trying to fixup.\n");
+ skipped = true;
+ continue;
+ }
orig_ret_address = (unsigned long)ri->ret_addr;
+ if (skipped)
+ pr_warn("%ps must be blacklisted because of incorrect kretprobe order\n",
+ ri->rp->kp.addr);
if (orig_ret_address != trampoline_address)
/*
@@ -808,14 +842,15 @@
if (ri->task != current)
/* another task is sharing our hash bucket */
continue;
+ if (ri->fp != frame_pointer)
+ continue;
orig_ret_address = (unsigned long)ri->ret_addr;
if (ri->rp && ri->rp->handler) {
__this_cpu_write(current_kprobe, &ri->rp->kp);
- get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE;
ri->ret_addr = correct_ret_addr;
ri->rp->handler(ri, regs);
- __this_cpu_write(current_kprobe, NULL);
+ __this_cpu_write(current_kprobe, &kretprobe_kprobe);
}
recycle_rp_inst(ri, &empty_rp);
@@ -831,6 +866,9 @@
kretprobe_hash_unlock(current, &flags);
+ __this_cpu_write(current_kprobe, NULL);
+ preempt_enable();
+
hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
hlist_del(&ri->hlist);
kfree(ri);
@@ -1020,64 +1058,23 @@
*/
if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
return 1;
-
- /*
- * In case the user-specified fault handler returned
- * zero, try to fix up.
- */
- if (fixup_exception(regs, trapnr))
- return 1;
-
- /*
- * fixup routine could not handle it,
- * Let do_page_fault() fix it.
- */
}
return 0;
}
NOKPROBE_SYMBOL(kprobe_fault_handler);
-/*
- * Wrapper routine for handling exceptions.
- */
-int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
- void *data)
+int __init arch_populate_kprobe_blacklist(void)
{
- struct die_args *args = data;
- int ret = NOTIFY_DONE;
+ int ret;
- if (args->regs && user_mode(args->regs))
+ ret = kprobe_add_area_blacklist((unsigned long)__irqentry_text_start,
+ (unsigned long)__irqentry_text_end);
+ if (ret)
return ret;
- if (val == DIE_GPF) {
- /*
- * To be potentially processing a kprobe fault and to
- * trust the result from kprobe_running(), we have
- * be non-preemptible.
- */
- if (!preemptible() && kprobe_running() &&
- kprobe_fault_handler(args->regs, args->trapnr))
- ret = NOTIFY_STOP;
- }
- return ret;
-}
-NOKPROBE_SYMBOL(kprobe_exceptions_notify);
-
-bool arch_within_kprobe_blacklist(unsigned long addr)
-{
- bool is_in_entry_trampoline_section = false;
-
-#ifdef CONFIG_X86_64
- is_in_entry_trampoline_section =
- (addr >= (unsigned long)__entry_trampoline_start &&
- addr < (unsigned long)__entry_trampoline_end);
-#endif
- return (addr >= (unsigned long)__kprobes_text_start &&
- addr < (unsigned long)__kprobes_text_end) ||
- (addr >= (unsigned long)__entry_text_start &&
- addr < (unsigned long)__entry_text_end) ||
- is_in_entry_trampoline_section;
+ return kprobe_add_area_blacklist((unsigned long)__entry_text_start,
+ (unsigned long)__entry_text_end);
}
int __init arch_init_kprobes(void)
diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c
index ef819e1..681a4b3 100644
--- a/arch/x86/kernel/kprobes/ftrace.c
+++ b/arch/x86/kernel/kprobes/ftrace.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Dynamic Ftrace based Kprobes Optimization
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
* Copyright (C) Hitachi Ltd., 2012
*/
#include <linux/kprobes.h>
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 6adf6e6..b348dd5 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Kernel Probes Jump Optimization (Optprobes)
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
* Copyright (C) IBM Corporation, 2002, 2004
* Copyright (C) Hitachi Ltd., 2012
*/
@@ -97,6 +84,7 @@
}
asm (
+ ".pushsection .rodata\n"
"optprobe_template_func:\n"
".global optprobe_template_entry\n"
"optprobe_template_entry:\n"
@@ -114,14 +102,15 @@
"optprobe_template_call:\n"
ASM_NOP5
/* Move flags to rsp */
- " movq 144(%rsp), %rdx\n"
- " movq %rdx, 152(%rsp)\n"
+ " movq 18*8(%rsp), %rdx\n"
+ " movq %rdx, 19*8(%rsp)\n"
RESTORE_REGS_STRING
/* Skip flags entry */
" addq $8, %rsp\n"
" popfq\n"
#else /* CONFIG_X86_32 */
- " pushf\n"
+ " pushl %esp\n"
+ " pushfl\n"
SAVE_REGS_STRING
" movl %esp, %edx\n"
".global optprobe_template_val\n"
@@ -130,14 +119,17 @@
".global optprobe_template_call\n"
"optprobe_template_call:\n"
ASM_NOP5
+ /* Move flags into esp */
+ " movl 14*4(%esp), %edx\n"
+ " movl %edx, 15*4(%esp)\n"
RESTORE_REGS_STRING
- " addl $4, %esp\n" /* skip cs */
- " popf\n"
+ /* Skip flags entry */
+ " addl $4, %esp\n"
+ " popfl\n"
#endif
".global optprobe_template_end\n"
"optprobe_template_end:\n"
- ".type optprobe_template_func, @function\n"
- ".size optprobe_template_func, .-optprobe_template_func\n");
+ ".popsection\n");
void optprobe_template_func(void);
STACK_FRAME_NON_STANDARD(optprobe_template_func);
@@ -165,10 +157,9 @@
} else {
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
/* Save skipped registers */
-#ifdef CONFIG_X86_64
regs->cs = __KERNEL_CS;
-#else
- regs->cs = __KERNEL_CS | get_kernel_rpl();
+#ifdef CONFIG_X86_32
+ regs->cs |= get_kernel_rpl();
regs->gs = 0;
#endif
regs->ip = (unsigned long)op->kp.addr + INT3_SIZE;
@@ -412,7 +403,7 @@
(u8 *)op->kp.addr + op->optinsn.size);
len += RELATIVEJUMP_SIZE;
- /* We have to use text_poke for instuction buffer because it is RO */
+ /* We have to use text_poke() for instruction buffer because it is RO */
text_poke(slot, buf, len);
ret = 0;
out:
@@ -431,7 +422,7 @@
void arch_optimize_kprobes(struct list_head *oplist)
{
struct optimized_kprobe *op, *tmp;
- u8 insn_buf[RELATIVEJUMP_SIZE];
+ u8 insn_buff[RELATIVEJUMP_SIZE];
list_for_each_entry_safe(op, tmp, oplist, list) {
s32 rel = (s32)((long)op->optinsn.insn -
@@ -443,10 +434,10 @@
memcpy(op->optinsn.copied_insn, op->kp.addr + INT3_SIZE,
RELATIVE_ADDR_SIZE);
- insn_buf[0] = RELATIVEJUMP_OPCODE;
- *(s32 *)(&insn_buf[1]) = rel;
+ insn_buff[0] = RELATIVEJUMP_OPCODE;
+ *(s32 *)(&insn_buff[1]) = rel;
- text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE,
+ text_poke_bp(op->kp.addr, insn_buff, RELATIVEJUMP_SIZE,
op->optinsn.insn);
list_del_init(&op->list);
@@ -456,12 +447,12 @@
/* Replace a relative jump with a breakpoint (int3). */
void arch_unoptimize_kprobe(struct optimized_kprobe *op)
{
- u8 insn_buf[RELATIVEJUMP_SIZE];
+ u8 insn_buff[RELATIVEJUMP_SIZE];
/* Set int3 to first byte for kprobes */
- insn_buf[0] = BREAKPOINT_INSTRUCTION;
- memcpy(insn_buf + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE);
- text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE,
+ insn_buff[0] = BREAKPOINT_INSTRUCTION;
+ memcpy(insn_buff + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE);
+ text_poke_bp(op->kp.addr, insn_buff, RELATIVEJUMP_SIZE,
op->optinsn.insn);
}