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Diffstat (limited to 'arch/powerpc/kernel/kprobes.c')
-rw-r--r--arch/powerpc/kernel/kprobes.c78
1 files changed, 40 insertions, 38 deletions
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index e8c2a6373157..cbc28d1a2e1b 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -19,11 +19,13 @@
#include <linux/extable.h>
#include <linux/kdebug.h>
#include <linux/slab.h>
+#include <linux/moduleloader.h>
#include <asm/code-patching.h>
#include <asm/cacheflush.h>
#include <asm/sstep.h>
#include <asm/sections.h>
#include <asm/inst.h>
+#include <asm/set_memory.h>
#include <linux/uaccess.h>
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
@@ -103,28 +105,42 @@ kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset)
return addr;
}
+void *alloc_insn_page(void)
+{
+ void *page;
+
+ page = module_alloc(PAGE_SIZE);
+ if (!page)
+ return NULL;
+
+ if (strict_module_rwx_enabled()) {
+ set_memory_ro((unsigned long)page, 1);
+ set_memory_x((unsigned long)page, 1);
+ }
+ return page;
+}
+
int arch_prepare_kprobe(struct kprobe *p)
{
int ret = 0;
struct kprobe *prev;
- struct ppc_inst insn = ppc_inst_read((struct ppc_inst *)p->addr);
+ struct ppc_inst insn = ppc_inst_read(p->addr);
if ((unsigned long)p->addr & 0x03) {
printk("Attempt to register kprobe at an unaligned address\n");
ret = -EINVAL;
- } else if (IS_MTMSRD(insn) || IS_RFID(insn) || IS_RFI(insn)) {
- printk("Cannot register a kprobe on rfi/rfid or mtmsr[d]\n");
+ } else if (IS_MTMSRD(insn) || IS_RFID(insn)) {
+ printk("Cannot register a kprobe on mtmsr[d]/rfi[d]\n");
ret = -EINVAL;
} else if ((unsigned long)p->addr & ~PAGE_MASK &&
- ppc_inst_prefixed(ppc_inst_read((struct ppc_inst *)(p->addr - 1)))) {
+ ppc_inst_prefixed(ppc_inst_read(p->addr - 1))) {
printk("Cannot register a kprobe on the second word of prefixed instruction\n");
ret = -EINVAL;
}
preempt_disable();
prev = get_kprobe(p->addr - 1);
preempt_enable_no_resched();
- if (prev &&
- ppc_inst_prefixed(ppc_inst_read((struct ppc_inst *)prev->ainsn.insn))) {
+ if (prev && ppc_inst_prefixed(ppc_inst_read(prev->ainsn.insn))) {
printk("Cannot register a kprobe on the second word of prefixed instruction\n");
ret = -EINVAL;
}
@@ -138,7 +154,7 @@ int arch_prepare_kprobe(struct kprobe *p)
}
if (!ret) {
- patch_instruction((struct ppc_inst *)p->ainsn.insn, insn);
+ patch_instruction(p->ainsn.insn, insn);
p->opcode = ppc_inst_val(insn);
}
@@ -149,13 +165,13 @@ NOKPROBE_SYMBOL(arch_prepare_kprobe);
void arch_arm_kprobe(struct kprobe *p)
{
- patch_instruction((struct ppc_inst *)p->addr, ppc_inst(BREAKPOINT_INSTRUCTION));
+ WARN_ON_ONCE(patch_instruction(p->addr, ppc_inst(BREAKPOINT_INSTRUCTION)));
}
NOKPROBE_SYMBOL(arch_arm_kprobe);
void arch_disarm_kprobe(struct kprobe *p)
{
- patch_instruction((struct ppc_inst *)p->addr, ppc_inst(p->opcode));
+ WARN_ON_ONCE(patch_instruction(p->addr, ppc_inst(p->opcode)));
}
NOKPROBE_SYMBOL(arch_disarm_kprobe);
@@ -178,7 +194,7 @@ static nokprobe_inline void prepare_singlestep(struct kprobe *p, struct pt_regs
* variant as values in regs could play a part in
* if the trap is taken or not
*/
- regs->nip = (unsigned long)p->ainsn.insn;
+ regs_set_return_ip(regs, (unsigned long)p->ainsn.insn);
}
static nokprobe_inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
@@ -228,7 +244,7 @@ NOKPROBE_SYMBOL(arch_prepare_kretprobe);
static int try_to_emulate(struct kprobe *p, struct pt_regs *regs)
{
int ret;
- struct ppc_inst insn = ppc_inst_read((struct ppc_inst *)p->ainsn.insn);
+ struct ppc_inst insn = ppc_inst_read(p->ainsn.insn);
/* regs->nip is also adjusted if emulate_step returns 1 */
ret = emulate_step(regs, insn);
@@ -319,8 +335,9 @@ int kprobe_handler(struct pt_regs *regs)
kprobe_opcode_t insn = *p->ainsn.insn;
if (kcb->kprobe_status == KPROBE_HIT_SS && is_trap(insn)) {
/* Turn off 'trace' bits */
- regs->msr &= ~MSR_SINGLESTEP;
- regs->msr |= kcb->kprobe_saved_msr;
+ regs_set_return_msr(regs,
+ (regs->msr & ~MSR_SINGLESTEP) |
+ kcb->kprobe_saved_msr);
goto no_kprobe;
}
@@ -415,7 +432,7 @@ static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
* we end up emulating it in kprobe_handler(), which increments the nip
* again.
*/
- regs->nip = orig_ret_address - 4;
+ regs_set_return_ip(regs, orig_ret_address - 4);
regs->link = orig_ret_address;
return 0;
@@ -439,7 +456,7 @@ int kprobe_post_handler(struct pt_regs *regs)
if (!cur || user_mode(regs))
return 0;
- len = ppc_inst_len(ppc_inst_read((struct ppc_inst *)cur->ainsn.insn));
+ len = ppc_inst_len(ppc_inst_read(cur->ainsn.insn));
/* make sure we got here for instruction we have a kprobe on */
if (((unsigned long)cur->ainsn.insn + len) != regs->nip)
return 0;
@@ -450,8 +467,8 @@ int kprobe_post_handler(struct pt_regs *regs)
}
/* Adjust nip to after the single-stepped instruction */
- regs->nip = (unsigned long)cur->addr + len;
- regs->msr |= kcb->kprobe_saved_msr;
+ regs_set_return_ip(regs, (unsigned long)cur->addr + len);
+ regs_set_return_msr(regs, regs->msr | kcb->kprobe_saved_msr);
/*Restore back the original saved kprobes variables and continue. */
if (kcb->kprobe_status == KPROBE_REENTER) {
@@ -490,9 +507,11 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
* and allow the page fault handler to continue as a
* normal page fault.
*/
- regs->nip = (unsigned long)cur->addr;
- regs->msr &= ~MSR_SINGLESTEP; /* Turn off 'trace' bits */
- regs->msr |= kcb->kprobe_saved_msr;
+ regs_set_return_ip(regs, (unsigned long)cur->addr);
+ /* Turn off 'trace' bits */
+ regs_set_return_msr(regs,
+ (regs->msr & ~MSR_SINGLESTEP) |
+ kcb->kprobe_saved_msr);
if (kcb->kprobe_status == KPROBE_REENTER)
restore_previous_kprobe(kcb);
else
@@ -502,28 +521,11 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
case KPROBE_HIT_ACTIVE:
case KPROBE_HIT_SSDONE:
/*
- * We increment the nmissed count for accounting,
- * we can also use npre/npostfault count for accounting
- * these specific fault cases.
- */
- kprobes_inc_nmissed_count(cur);
-
- /*
- * We come here because instructions in the pre/post
- * handler caused the page_fault, this could happen
- * if handler tries to access user space by
- * copy_from_user(), get_user() etc. Let the
- * user-specified handler try to fix it first.
- */
- 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 ((entry = search_exception_tables(regs->nip)) != NULL) {
- regs->nip = extable_fixup(entry);
+ regs_set_return_ip(regs, extable_fixup(entry));
return 1;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-08 18:42:36 +0300