kmemcheck: add the kmemcheck core
General description: kmemcheck is a patch to the linux kernel that detects use of uninitialized memory. It does this by trapping every read and write to memory that was allocated dynamically (e.g. using kmalloc()). If a memory address is read that has not previously been written to, a message is printed to the kernel log. Thanks to Andi Kleen for the set_memory_4k() solution. Andrew Morton suggested documenting the shadow member of struct page. Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> [export kmemcheck_mark_initialized] [build fix for setup_max_cpus] Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
This commit is contained in:
Vegard Nossum
parent
e594c8de3b
commit
dfec072ecd
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@ -81,6 +81,11 @@ ifdef CONFIG_CC_STACKPROTECTOR
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endif
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endif
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# Don't unroll struct assignments with kmemcheck enabled
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ifeq ($(CONFIG_KMEMCHECK),y)
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KBUILD_CFLAGS += $(call cc-option,-fno-builtin-memcpy)
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endif
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# Stackpointer is addressed different for 32 bit and 64 bit x86
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sp-$(CONFIG_X86_32) := esp
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sp-$(CONFIG_X86_64) := rsp
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@ -0,0 +1,42 @@
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#ifndef ASM_X86_KMEMCHECK_H
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#define ASM_X86_KMEMCHECK_H
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#include <linux/types.h>
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#include <asm/ptrace.h>
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#ifdef CONFIG_KMEMCHECK
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bool kmemcheck_active(struct pt_regs *regs);
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void kmemcheck_show(struct pt_regs *regs);
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void kmemcheck_hide(struct pt_regs *regs);
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bool kmemcheck_fault(struct pt_regs *regs,
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unsigned long address, unsigned long error_code);
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bool kmemcheck_trap(struct pt_regs *regs);
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#else
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static inline bool kmemcheck_active(struct pt_regs *regs)
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{
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return false;
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}
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static inline void kmemcheck_show(struct pt_regs *regs)
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{
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}
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static inline void kmemcheck_hide(struct pt_regs *regs)
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{
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}
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static inline bool kmemcheck_fault(struct pt_regs *regs,
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unsigned long address, unsigned long error_code)
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{
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return false;
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}
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static inline bool kmemcheck_trap(struct pt_regs *regs)
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{
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return false;
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}
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#endif /* CONFIG_KMEMCHECK */
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#endif
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@ -317,6 +317,15 @@ static inline int pte_present(pte_t a)
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return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE);
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}
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static inline int pte_hidden(pte_t x)
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{
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#ifdef CONFIG_KMEMCHECK
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return pte_flags(x) & _PAGE_HIDDEN;
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#else
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return 0;
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#endif
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}
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static inline int pmd_present(pmd_t pmd)
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{
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return pmd_flags(pmd) & _PAGE_PRESENT;
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@ -18,7 +18,7 @@
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#define _PAGE_BIT_GLOBAL 8 /* Global TLB entry PPro+ */
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#define _PAGE_BIT_UNUSED1 9 /* available for programmer */
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#define _PAGE_BIT_IOMAP 10 /* flag used to indicate IO mapping */
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#define _PAGE_BIT_UNUSED3 11
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#define _PAGE_BIT_HIDDEN 11 /* hidden by kmemcheck */
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#define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */
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#define _PAGE_BIT_SPECIAL _PAGE_BIT_UNUSED1
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#define _PAGE_BIT_CPA_TEST _PAGE_BIT_UNUSED1
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@ -41,7 +41,7 @@
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#define _PAGE_GLOBAL (_AT(pteval_t, 1) << _PAGE_BIT_GLOBAL)
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#define _PAGE_UNUSED1 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED1)
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#define _PAGE_IOMAP (_AT(pteval_t, 1) << _PAGE_BIT_IOMAP)
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#define _PAGE_UNUSED3 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED3)
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#define _PAGE_HIDDEN (_AT(pteval_t, 1) << _PAGE_BIT_HIDDEN)
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#define _PAGE_PAT (_AT(pteval_t, 1) << _PAGE_BIT_PAT)
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#define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
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#define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL)
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@ -10,6 +10,8 @@ obj-$(CONFIG_X86_PTDUMP) += dump_pagetables.o
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obj-$(CONFIG_HIGHMEM) += highmem_32.o
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obj-$(CONFIG_KMEMCHECK) += kmemcheck/
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obj-$(CONFIG_MMIOTRACE) += mmiotrace.o
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mmiotrace-y := kmmio.o pf_in.o mmio-mod.o
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obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o
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@ -0,0 +1 @@
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obj-y := error.o kmemcheck.o opcode.o pte.o shadow.o
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@ -0,0 +1,229 @@
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#include <linux/interrupt.h>
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#include <linux/kdebug.h>
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#include <linux/kmemcheck.h>
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#include <linux/kernel.h>
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#include <linux/types.h>
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#include <linux/ptrace.h>
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#include <linux/stacktrace.h>
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#include <linux/string.h>
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#include "error.h"
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#include "shadow.h"
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enum kmemcheck_error_type {
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KMEMCHECK_ERROR_INVALID_ACCESS,
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KMEMCHECK_ERROR_BUG,
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};
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#define SHADOW_COPY_SIZE (1 << CONFIG_KMEMCHECK_SHADOW_COPY_SHIFT)
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struct kmemcheck_error {
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enum kmemcheck_error_type type;
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union {
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/* KMEMCHECK_ERROR_INVALID_ACCESS */
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struct {
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/* Kind of access that caused the error */
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enum kmemcheck_shadow state;
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/* Address and size of the erroneous read */
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unsigned long address;
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unsigned int size;
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};
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};
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struct pt_regs regs;
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struct stack_trace trace;
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unsigned long trace_entries[32];
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/* We compress it to a char. */
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unsigned char shadow_copy[SHADOW_COPY_SIZE];
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unsigned char memory_copy[SHADOW_COPY_SIZE];
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};
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/*
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* Create a ring queue of errors to output. We can't call printk() directly
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* from the kmemcheck traps, since this may call the console drivers and
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* result in a recursive fault.
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*/
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static struct kmemcheck_error error_fifo[CONFIG_KMEMCHECK_QUEUE_SIZE];
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static unsigned int error_count;
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static unsigned int error_rd;
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static unsigned int error_wr;
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static unsigned int error_missed_count;
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static struct kmemcheck_error *error_next_wr(void)
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{
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struct kmemcheck_error *e;
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if (error_count == ARRAY_SIZE(error_fifo)) {
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++error_missed_count;
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return NULL;
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}
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e = &error_fifo[error_wr];
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if (++error_wr == ARRAY_SIZE(error_fifo))
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error_wr = 0;
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++error_count;
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return e;
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}
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static struct kmemcheck_error *error_next_rd(void)
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{
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struct kmemcheck_error *e;
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if (error_count == 0)
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return NULL;
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e = &error_fifo[error_rd];
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if (++error_rd == ARRAY_SIZE(error_fifo))
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error_rd = 0;
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--error_count;
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return e;
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}
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static void do_wakeup(unsigned long);
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static DECLARE_TASKLET(kmemcheck_tasklet, &do_wakeup, 0);
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/*
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* Save the context of an error report.
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*/
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void kmemcheck_error_save(enum kmemcheck_shadow state,
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unsigned long address, unsigned int size, struct pt_regs *regs)
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{
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static unsigned long prev_ip;
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struct kmemcheck_error *e;
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void *shadow_copy;
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void *memory_copy;
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/* Don't report several adjacent errors from the same EIP. */
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if (regs->ip == prev_ip)
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return;
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prev_ip = regs->ip;
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e = error_next_wr();
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if (!e)
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return;
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e->type = KMEMCHECK_ERROR_INVALID_ACCESS;
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e->state = state;
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e->address = address;
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e->size = size;
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/* Save regs */
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memcpy(&e->regs, regs, sizeof(*regs));
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/* Save stack trace */
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e->trace.nr_entries = 0;
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e->trace.entries = e->trace_entries;
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e->trace.max_entries = ARRAY_SIZE(e->trace_entries);
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e->trace.skip = 0;
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save_stack_trace_bp(&e->trace, regs->bp);
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/* Round address down to nearest 16 bytes */
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shadow_copy = kmemcheck_shadow_lookup(address
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& ~(SHADOW_COPY_SIZE - 1));
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BUG_ON(!shadow_copy);
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memcpy(e->shadow_copy, shadow_copy, SHADOW_COPY_SIZE);
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kmemcheck_show_addr(address);
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memory_copy = (void *) (address & ~(SHADOW_COPY_SIZE - 1));
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memcpy(e->memory_copy, memory_copy, SHADOW_COPY_SIZE);
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kmemcheck_hide_addr(address);
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tasklet_hi_schedule_first(&kmemcheck_tasklet);
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}
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/*
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* Save the context of a kmemcheck bug.
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*/
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void kmemcheck_error_save_bug(struct pt_regs *regs)
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{
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struct kmemcheck_error *e;
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e = error_next_wr();
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if (!e)
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return;
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e->type = KMEMCHECK_ERROR_BUG;
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memcpy(&e->regs, regs, sizeof(*regs));
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e->trace.nr_entries = 0;
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e->trace.entries = e->trace_entries;
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e->trace.max_entries = ARRAY_SIZE(e->trace_entries);
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e->trace.skip = 1;
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save_stack_trace(&e->trace);
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tasklet_hi_schedule_first(&kmemcheck_tasklet);
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}
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void kmemcheck_error_recall(void)
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{
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static const char *desc[] = {
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[KMEMCHECK_SHADOW_UNALLOCATED] = "unallocated",
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[KMEMCHECK_SHADOW_UNINITIALIZED] = "uninitialized",
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[KMEMCHECK_SHADOW_INITIALIZED] = "initialized",
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[KMEMCHECK_SHADOW_FREED] = "freed",
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};
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static const char short_desc[] = {
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[KMEMCHECK_SHADOW_UNALLOCATED] = 'a',
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[KMEMCHECK_SHADOW_UNINITIALIZED] = 'u',
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[KMEMCHECK_SHADOW_INITIALIZED] = 'i',
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[KMEMCHECK_SHADOW_FREED] = 'f',
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};
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struct kmemcheck_error *e;
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unsigned int i;
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e = error_next_rd();
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if (!e)
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return;
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switch (e->type) {
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case KMEMCHECK_ERROR_INVALID_ACCESS:
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printk(KERN_ERR "WARNING: kmemcheck: Caught %d-bit read "
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"from %s memory (%p)\n",
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8 * e->size, e->state < ARRAY_SIZE(desc) ?
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desc[e->state] : "(invalid shadow state)",
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(void *) e->address);
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printk(KERN_INFO);
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for (i = 0; i < SHADOW_COPY_SIZE; ++i)
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printk("%02x", e->memory_copy[i]);
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printk("\n");
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printk(KERN_INFO);
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for (i = 0; i < SHADOW_COPY_SIZE; ++i) {
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if (e->shadow_copy[i] < ARRAY_SIZE(short_desc))
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printk(" %c", short_desc[e->shadow_copy[i]]);
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else
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printk(" ?");
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}
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printk("\n");
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printk(KERN_INFO "%*c\n", 2 + 2
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* (int) (e->address & (SHADOW_COPY_SIZE - 1)), '^');
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break;
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case KMEMCHECK_ERROR_BUG:
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printk(KERN_EMERG "ERROR: kmemcheck: Fatal error\n");
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break;
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}
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__show_regs(&e->regs, 1);
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print_stack_trace(&e->trace, 0);
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}
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static void do_wakeup(unsigned long data)
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{
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while (error_count > 0)
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kmemcheck_error_recall();
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if (error_missed_count > 0) {
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printk(KERN_WARNING "kmemcheck: Lost %d error reports because "
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"the queue was too small\n", error_missed_count);
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error_missed_count = 0;
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}
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}
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@ -0,0 +1,15 @@
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#ifndef ARCH__X86__MM__KMEMCHECK__ERROR_H
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#define ARCH__X86__MM__KMEMCHECK__ERROR_H
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#include <linux/ptrace.h>
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#include "shadow.h"
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void kmemcheck_error_save(enum kmemcheck_shadow state,
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unsigned long address, unsigned int size, struct pt_regs *regs);
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void kmemcheck_error_save_bug(struct pt_regs *regs);
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void kmemcheck_error_recall(void);
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#endif
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@ -0,0 +1,650 @@
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/**
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* kmemcheck - a heavyweight memory checker for the linux kernel
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* Copyright (C) 2007, 2008 Vegard Nossum <vegardno@ifi.uio.no>
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* (With a lot of help from Ingo Molnar and Pekka Enberg.)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License (version 2) as
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* published by the Free Software Foundation.
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*/
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/kallsyms.h>
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#include <linux/kernel.h>
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#include <linux/kmemcheck.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/page-flags.h>
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#include <linux/percpu.h>
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#include <linux/ptrace.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <asm/cacheflush.h>
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#include <asm/kmemcheck.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include "error.h"
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#include "opcode.h"
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#include "pte.h"
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#include "shadow.h"
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#ifdef CONFIG_KMEMCHECK_DISABLED_BY_DEFAULT
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# define KMEMCHECK_ENABLED 0
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#endif
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#ifdef CONFIG_KMEMCHECK_ENABLED_BY_DEFAULT
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# define KMEMCHECK_ENABLED 1
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#endif
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#ifdef CONFIG_KMEMCHECK_ONESHOT_BY_DEFAULT
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# define KMEMCHECK_ENABLED 2
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#endif
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int kmemcheck_enabled = KMEMCHECK_ENABLED;
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int __init kmemcheck_init(void)
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{
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printk(KERN_INFO "kmemcheck: \"Bugs, beware!\"\n");
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#ifdef CONFIG_SMP
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/*
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* Limit SMP to use a single CPU. We rely on the fact that this code
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* runs before SMP is set up.
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*/
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if (setup_max_cpus > 1) {
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printk(KERN_INFO
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"kmemcheck: Limiting number of CPUs to 1.\n");
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setup_max_cpus = 1;
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}
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#endif
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return 0;
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}
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early_initcall(kmemcheck_init);
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#ifdef CONFIG_KMEMCHECK_DISABLED_BY_DEFAULT
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int kmemcheck_enabled = 0;
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#endif
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#ifdef CONFIG_KMEMCHECK_ENABLED_BY_DEFAULT
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int kmemcheck_enabled = 1;
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#endif
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#ifdef CONFIG_KMEMCHECK_ONESHOT_BY_DEFAULT
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int kmemcheck_enabled = 2;
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#endif
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/*
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* We need to parse the kmemcheck= option before any memory is allocated.
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*/
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static int __init param_kmemcheck(char *str)
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{
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if (!str)
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return -EINVAL;
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sscanf(str, "%d", &kmemcheck_enabled);
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return 0;
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}
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early_param("kmemcheck", param_kmemcheck);
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int kmemcheck_show_addr(unsigned long address)
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{
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pte_t *pte;
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pte = kmemcheck_pte_lookup(address);
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if (!pte)
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return 0;
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set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
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__flush_tlb_one(address);
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return 1;
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}
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int kmemcheck_hide_addr(unsigned long address)
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{
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pte_t *pte;
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pte = kmemcheck_pte_lookup(address);
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if (!pte)
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return 0;
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set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
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__flush_tlb_one(address);
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return 1;
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}
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struct kmemcheck_context {
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bool busy;
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int balance;
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/*
|
||||
* There can be at most two memory operands to an instruction, but
|
||||
* each address can cross a page boundary -- so we may need up to
|
||||
* four addresses that must be hidden/revealed for each fault.
|
||||
*/
|
||||
unsigned long addr[4];
|
||||
unsigned long n_addrs;
|
||||
unsigned long flags;
|
||||
|
||||
/* Data size of the instruction that caused a fault. */
|
||||
unsigned int size;
|
||||
};
|
||||
|
||||
static DEFINE_PER_CPU(struct kmemcheck_context, kmemcheck_context);
|
||||
|
||||
bool kmemcheck_active(struct pt_regs *regs)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
|
||||
return data->balance > 0;
|
||||
}
|
||||
|
||||
/* Save an address that needs to be shown/hidden */
|
||||
static void kmemcheck_save_addr(unsigned long addr)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
|
||||
BUG_ON(data->n_addrs >= ARRAY_SIZE(data->addr));
|
||||
data->addr[data->n_addrs++] = addr;
|
||||
}
|
||||
|
||||
static unsigned int kmemcheck_show_all(void)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
unsigned int i;
|
||||
unsigned int n;
|
||||
|
||||
n = 0;
|
||||
for (i = 0; i < data->n_addrs; ++i)
|
||||
n += kmemcheck_show_addr(data->addr[i]);
|
||||
|
||||
return n;
|
||||
}
|
||||
|
||||
static unsigned int kmemcheck_hide_all(void)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
unsigned int i;
|
||||
unsigned int n;
|
||||
|
||||
n = 0;
|
||||
for (i = 0; i < data->n_addrs; ++i)
|
||||
n += kmemcheck_hide_addr(data->addr[i]);
|
||||
|
||||
return n;
|
||||
}
|
||||
|
||||
/*
|
||||
* Called from the #PF handler.
|
||||
*/
|
||||
void kmemcheck_show(struct pt_regs *regs)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
|
||||
BUG_ON(!irqs_disabled());
|
||||
|
||||
if (unlikely(data->balance != 0)) {
|
||||
kmemcheck_show_all();
|
||||
kmemcheck_error_save_bug(regs);
|
||||
data->balance = 0;
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* None of the addresses actually belonged to kmemcheck. Note that
|
||||
* this is not an error.
|
||||
*/
|
||||
if (kmemcheck_show_all() == 0)
|
||||
return;
|
||||
|
||||
++data->balance;
|
||||
|
||||
/*
|
||||
* The IF needs to be cleared as well, so that the faulting
|
||||
* instruction can run "uninterrupted". Otherwise, we might take
|
||||
* an interrupt and start executing that before we've had a chance
|
||||
* to hide the page again.
|
||||
*
|
||||
* NOTE: In the rare case of multiple faults, we must not override
|
||||
* the original flags:
|
||||
*/
|
||||
if (!(regs->flags & X86_EFLAGS_TF))
|
||||
data->flags = regs->flags;
|
||||
|
||||
regs->flags |= X86_EFLAGS_TF;
|
||||
regs->flags &= ~X86_EFLAGS_IF;
|
||||
}
|
||||
|
||||
/*
|
||||
* Called from the #DB handler.
|
||||
*/
|
||||
void kmemcheck_hide(struct pt_regs *regs)
|
||||
{
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
int n;
|
||||
|
||||
BUG_ON(!irqs_disabled());
|
||||
|
||||
if (data->balance == 0)
|
||||
return;
|
||||
|
||||
if (unlikely(data->balance != 1)) {
|
||||
kmemcheck_show_all();
|
||||
kmemcheck_error_save_bug(regs);
|
||||
data->n_addrs = 0;
|
||||
data->balance = 0;
|
||||
|
||||
if (!(data->flags & X86_EFLAGS_TF))
|
||||
regs->flags &= ~X86_EFLAGS_TF;
|
||||
if (data->flags & X86_EFLAGS_IF)
|
||||
regs->flags |= X86_EFLAGS_IF;
|
||||
return;
|
||||
}
|
||||
|
||||
if (kmemcheck_enabled)
|
||||
n = kmemcheck_hide_all();
|
||||
else
|
||||
n = kmemcheck_show_all();
|
||||
|
||||
if (n == 0)
|
||||
return;
|
||||
|
||||
--data->balance;
|
||||
|
||||
data->n_addrs = 0;
|
||||
|
||||
if (!(data->flags & X86_EFLAGS_TF))
|
||||
regs->flags &= ~X86_EFLAGS_TF;
|
||||
if (data->flags & X86_EFLAGS_IF)
|
||||
regs->flags |= X86_EFLAGS_IF;
|
||||
}
|
||||
|
||||
void kmemcheck_show_pages(struct page *p, unsigned int n)
|
||||
{
|
||||
unsigned int i;
|
||||
|
||||
for (i = 0; i < n; ++i) {
|
||||
unsigned long address;
|
||||
pte_t *pte;
|
||||
unsigned int level;
|
||||
|
||||
address = (unsigned long) page_address(&p[i]);
|
||||
pte = lookup_address(address, &level);
|
||||
BUG_ON(!pte);
|
||||
BUG_ON(level != PG_LEVEL_4K);
|
||||
|
||||
set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
|
||||
set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_HIDDEN));
|
||||
__flush_tlb_one(address);
|
||||
}
|
||||
}
|
||||
|
||||
bool kmemcheck_page_is_tracked(struct page *p)
|
||||
{
|
||||
/* This will also check the "hidden" flag of the PTE. */
|
||||
return kmemcheck_pte_lookup((unsigned long) page_address(p));
|
||||
}
|
||||
|
||||
void kmemcheck_hide_pages(struct page *p, unsigned int n)
|
||||
{
|
||||
unsigned int i;
|
||||
|
||||
for (i = 0; i < n; ++i) {
|
||||
unsigned long address;
|
||||
pte_t *pte;
|
||||
unsigned int level;
|
||||
|
||||
address = (unsigned long) page_address(&p[i]);
|
||||
pte = lookup_address(address, &level);
|
||||
BUG_ON(!pte);
|
||||
BUG_ON(level != PG_LEVEL_4K);
|
||||
|
||||
set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
|
||||
set_pte(pte, __pte(pte_val(*pte) | _PAGE_HIDDEN));
|
||||
__flush_tlb_one(address);
|
||||
}
|
||||
}
|
||||
|
||||
/* Access may NOT cross page boundary */
|
||||
static void kmemcheck_read_strict(struct pt_regs *regs,
|
||||
unsigned long addr, unsigned int size)
|
||||
{
|
||||
void *shadow;
|
||||
enum kmemcheck_shadow status;
|
||||
|
||||
shadow = kmemcheck_shadow_lookup(addr);
|
||||
if (!shadow)
|
||||
return;
|
||||
|
||||
kmemcheck_save_addr(addr);
|
||||
status = kmemcheck_shadow_test(shadow, size);
|
||||
if (status == KMEMCHECK_SHADOW_INITIALIZED)
|
||||
return;
|
||||
|
||||
if (kmemcheck_enabled)
|
||||
kmemcheck_error_save(status, addr, size, regs);
|
||||
|
||||
if (kmemcheck_enabled == 2)
|
||||
kmemcheck_enabled = 0;
|
||||
|
||||
/* Don't warn about it again. */
|
||||
kmemcheck_shadow_set(shadow, size);
|
||||
}
|
||||
|
||||
/* Access may cross page boundary */
|
||||
static void kmemcheck_read(struct pt_regs *regs,
|
||||
unsigned long addr, unsigned int size)
|
||||
{
|
||||
unsigned long page = addr & PAGE_MASK;
|
||||
unsigned long next_addr = addr + size - 1;
|
||||
unsigned long next_page = next_addr & PAGE_MASK;
|
||||
|
||||
if (likely(page == next_page)) {
|
||||
kmemcheck_read_strict(regs, addr, size);
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* What we do is basically to split the access across the
|
||||
* two pages and handle each part separately. Yes, this means
|
||||
* that we may now see reads that are 3 + 5 bytes, for
|
||||
* example (and if both are uninitialized, there will be two
|
||||
* reports), but it makes the code a lot simpler.
|
||||
*/
|
||||
kmemcheck_read_strict(regs, addr, next_page - addr);
|
||||
kmemcheck_read_strict(regs, next_page, next_addr - next_page);
|
||||
}
|
||||
|
||||
static void kmemcheck_write_strict(struct pt_regs *regs,
|
||||
unsigned long addr, unsigned int size)
|
||||
{
|
||||
void *shadow;
|
||||
|
||||
shadow = kmemcheck_shadow_lookup(addr);
|
||||
if (!shadow)
|
||||
return;
|
||||
|
||||
kmemcheck_save_addr(addr);
|
||||
kmemcheck_shadow_set(shadow, size);
|
||||
}
|
||||
|
||||
static void kmemcheck_write(struct pt_regs *regs,
|
||||
unsigned long addr, unsigned int size)
|
||||
{
|
||||
unsigned long page = addr & PAGE_MASK;
|
||||
unsigned long next_addr = addr + size - 1;
|
||||
unsigned long next_page = next_addr & PAGE_MASK;
|
||||
|
||||
if (likely(page == next_page)) {
|
||||
kmemcheck_write_strict(regs, addr, size);
|
||||
return;
|
||||
}
|
||||
|
||||
/* See comment in kmemcheck_read(). */
|
||||
kmemcheck_write_strict(regs, addr, next_page - addr);
|
||||
kmemcheck_write_strict(regs, next_page, next_addr - next_page);
|
||||
}
|
||||
|
||||
/*
|
||||
* Copying is hard. We have two addresses, each of which may be split across
|
||||
* a page (and each page will have different shadow addresses).
|
||||
*/
|
||||
static void kmemcheck_copy(struct pt_regs *regs,
|
||||
unsigned long src_addr, unsigned long dst_addr, unsigned int size)
|
||||
{
|
||||
uint8_t shadow[8];
|
||||
enum kmemcheck_shadow status;
|
||||
|
||||
unsigned long page;
|
||||
unsigned long next_addr;
|
||||
unsigned long next_page;
|
||||
|
||||
uint8_t *x;
|
||||
unsigned int i;
|
||||
unsigned int n;
|
||||
|
||||
BUG_ON(size > sizeof(shadow));
|
||||
|
||||
page = src_addr & PAGE_MASK;
|
||||
next_addr = src_addr + size - 1;
|
||||
next_page = next_addr & PAGE_MASK;
|
||||
|
||||
if (likely(page == next_page)) {
|
||||
/* Same page */
|
||||
x = kmemcheck_shadow_lookup(src_addr);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(src_addr);
|
||||
for (i = 0; i < size; ++i)
|
||||
shadow[i] = x[i];
|
||||
} else {
|
||||
for (i = 0; i < size; ++i)
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
} else {
|
||||
n = next_page - src_addr;
|
||||
BUG_ON(n > sizeof(shadow));
|
||||
|
||||
/* First page */
|
||||
x = kmemcheck_shadow_lookup(src_addr);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(src_addr);
|
||||
for (i = 0; i < n; ++i)
|
||||
shadow[i] = x[i];
|
||||
} else {
|
||||
/* Not tracked */
|
||||
for (i = 0; i < n; ++i)
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
|
||||
/* Second page */
|
||||
x = kmemcheck_shadow_lookup(next_page);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(next_page);
|
||||
for (i = n; i < size; ++i)
|
||||
shadow[i] = x[i - n];
|
||||
} else {
|
||||
/* Not tracked */
|
||||
for (i = n; i < size; ++i)
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
}
|
||||
|
||||
page = dst_addr & PAGE_MASK;
|
||||
next_addr = dst_addr + size - 1;
|
||||
next_page = next_addr & PAGE_MASK;
|
||||
|
||||
if (likely(page == next_page)) {
|
||||
/* Same page */
|
||||
x = kmemcheck_shadow_lookup(dst_addr);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(dst_addr);
|
||||
for (i = 0; i < size; ++i) {
|
||||
x[i] = shadow[i];
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
n = next_page - dst_addr;
|
||||
BUG_ON(n > sizeof(shadow));
|
||||
|
||||
/* First page */
|
||||
x = kmemcheck_shadow_lookup(dst_addr);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(dst_addr);
|
||||
for (i = 0; i < n; ++i) {
|
||||
x[i] = shadow[i];
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
}
|
||||
|
||||
/* Second page */
|
||||
x = kmemcheck_shadow_lookup(next_page);
|
||||
if (x) {
|
||||
kmemcheck_save_addr(next_page);
|
||||
for (i = n; i < size; ++i) {
|
||||
x[i - n] = shadow[i];
|
||||
shadow[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
status = kmemcheck_shadow_test(shadow, size);
|
||||
if (status == KMEMCHECK_SHADOW_INITIALIZED)
|
||||
return;
|
||||
|
||||
if (kmemcheck_enabled)
|
||||
kmemcheck_error_save(status, src_addr, size, regs);
|
||||
|
||||
if (kmemcheck_enabled == 2)
|
||||
kmemcheck_enabled = 0;
|
||||
}
|
||||
|
||||
enum kmemcheck_method {
|
||||
KMEMCHECK_READ,
|
||||
KMEMCHECK_WRITE,
|
||||
};
|
||||
|
||||
static void kmemcheck_access(struct pt_regs *regs,
|
||||
unsigned long fallback_address, enum kmemcheck_method fallback_method)
|
||||
{
|
||||
const uint8_t *insn;
|
||||
const uint8_t *insn_primary;
|
||||
unsigned int size;
|
||||
|
||||
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
|
||||
|
||||
/* Recursive fault -- ouch. */
|
||||
if (data->busy) {
|
||||
kmemcheck_show_addr(fallback_address);
|
||||
kmemcheck_error_save_bug(regs);
|
||||
return;
|
||||
}
|
||||
|
||||
data->busy = true;
|
||||
|
||||
insn = (const uint8_t *) regs->ip;
|
||||
insn_primary = kmemcheck_opcode_get_primary(insn);
|
||||
|
||||
kmemcheck_opcode_decode(insn, &size);
|
||||
|
||||
switch (insn_primary[0]) {
|
||||
#ifdef CONFIG_KMEMCHECK_BITOPS_OK
|
||||
/* AND, OR, XOR */
|
||||
/*
|
||||
* Unfortunately, these instructions have to be excluded from
|
||||
* our regular checking since they access only some (and not
|
||||
* all) bits. This clears out "bogus" bitfield-access warnings.
|
||||
*/
|
||||
case 0x80:
|
||||
case 0x81:
|
||||
case 0x82:
|
||||
case 0x83:
|
||||
switch ((insn_primary[1] >> 3) & 7) {
|
||||
/* OR */
|
||||
case 1:
|
||||
/* AND */
|
||||
case 4:
|
||||
/* XOR */
|
||||
case 6:
|
||||
kmemcheck_write(regs, fallback_address, size);
|
||||
goto out;
|
||||
|
||||
/* ADD */
|
||||
case 0:
|
||||
/* ADC */
|
||||
case 2:
|
||||
/* SBB */
|
||||
case 3:
|
||||
/* SUB */
|
||||
case 5:
|
||||
/* CMP */
|
||||
case 7:
|
||||
break;
|
||||
}
|
||||
break;
|
||||
#endif
|
||||
|
||||
/* MOVS, MOVSB, MOVSW, MOVSD */
|
||||
case 0xa4:
|
||||
case 0xa5:
|
||||
/*
|
||||
* These instructions are special because they take two
|
||||
* addresses, but we only get one page fault.
|
||||
*/
|
||||
kmemcheck_copy(regs, regs->si, regs->di, size);
|
||||
goto out;
|
||||
|
||||
/* CMPS, CMPSB, CMPSW, CMPSD */
|
||||
case 0xa6:
|
||||
case 0xa7:
|
||||
kmemcheck_read(regs, regs->si, size);
|
||||
kmemcheck_read(regs, regs->di, size);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/*
|
||||
* If the opcode isn't special in any way, we use the data from the
|
||||
* page fault handler to determine the address and type of memory
|
||||
* access.
|
||||
*/
|
||||
switch (fallback_method) {
|
||||
case KMEMCHECK_READ:
|
||||
kmemcheck_read(regs, fallback_address, size);
|
||||
goto out;
|
||||
case KMEMCHECK_WRITE:
|
||||
kmemcheck_write(regs, fallback_address, size);
|
||||
goto out;
|
||||
}
|
||||
|
||||
out:
|
||||
data->busy = false;
|
||||
}
|
||||
|
||||
bool kmemcheck_fault(struct pt_regs *regs, unsigned long address,
|
||||
unsigned long error_code)
|
||||
{
|
||||
pte_t *pte;
|
||||
unsigned int level;
|
||||
|
||||
/*
|
||||
* XXX: Is it safe to assume that memory accesses from virtual 86
|
||||
* mode or non-kernel code segments will _never_ access kernel
|
||||
* memory (e.g. tracked pages)? For now, we need this to avoid
|
||||
* invoking kmemcheck for PnP BIOS calls.
|
||||
*/
|
||||
if (regs->flags & X86_VM_MASK)
|
||||
return false;
|
||||
if (regs->cs != __KERNEL_CS)
|
||||
return false;
|
||||
|
||||
pte = lookup_address(address, &level);
|
||||
if (!pte)
|
||||
return false;
|
||||
if (level != PG_LEVEL_4K)
|
||||
return false;
|
||||
if (!pte_hidden(*pte))
|
||||
return false;
|
||||
|
||||
if (error_code & 2)
|
||||
kmemcheck_access(regs, address, KMEMCHECK_WRITE);
|
||||
else
|
||||
kmemcheck_access(regs, address, KMEMCHECK_READ);
|
||||
|
||||
kmemcheck_show(regs);
|
||||
return true;
|
||||
}
|
||||
|
||||
bool kmemcheck_trap(struct pt_regs *regs)
|
||||
{
|
||||
if (!kmemcheck_active(regs))
|
||||
return false;
|
||||
|
||||
/* We're done. */
|
||||
kmemcheck_hide(regs);
|
||||
return true;
|
||||
}
|
||||
|
|
@ -0,0 +1,101 @@
|
|||
#include <linux/types.h>
|
||||
|
||||
#include "opcode.h"
|
||||
|
||||
static bool opcode_is_prefix(uint8_t b)
|
||||
{
|
||||
return
|
||||
/* Group 1 */
|
||||
b == 0xf0 || b == 0xf2 || b == 0xf3
|
||||
/* Group 2 */
|
||||
|| b == 0x2e || b == 0x36 || b == 0x3e || b == 0x26
|
||||
|| b == 0x64 || b == 0x65 || b == 0x2e || b == 0x3e
|
||||
/* Group 3 */
|
||||
|| b == 0x66
|
||||
/* Group 4 */
|
||||
|| b == 0x67;
|
||||
}
|
||||
|
||||
static bool opcode_is_rex_prefix(uint8_t b)
|
||||
{
|
||||
return (b & 0xf0) == 0x40;
|
||||
}
|
||||
|
||||
#define REX_W (1 << 3)
|
||||
|
||||
/*
|
||||
* This is a VERY crude opcode decoder. We only need to find the size of the
|
||||
* load/store that caused our #PF and this should work for all the opcodes
|
||||
* that we care about. Moreover, the ones who invented this instruction set
|
||||
* should be shot.
|
||||
*/
|
||||
void kmemcheck_opcode_decode(const uint8_t *op, unsigned int *size)
|
||||
{
|
||||
/* Default operand size */
|
||||
int operand_size_override = 4;
|
||||
|
||||
/* prefixes */
|
||||
for (; opcode_is_prefix(*op); ++op) {
|
||||
if (*op == 0x66)
|
||||
operand_size_override = 2;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_X86_64
|
||||
/* REX prefix */
|
||||
if (opcode_is_rex_prefix(*op)) {
|
||||
uint8_t rex = *op;
|
||||
|
||||
++op;
|
||||
if (rex & REX_W) {
|
||||
switch (*op) {
|
||||
case 0x63:
|
||||
*size = 4;
|
||||
return;
|
||||
case 0x0f:
|
||||
++op;
|
||||
|
||||
switch (*op) {
|
||||
case 0xb6:
|
||||
case 0xbe:
|
||||
*size = 1;
|
||||
return;
|
||||
case 0xb7:
|
||||
case 0xbf:
|
||||
*size = 2;
|
||||
return;
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
*size = 8;
|
||||
return;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
/* escape opcode */
|
||||
if (*op == 0x0f) {
|
||||
++op;
|
||||
|
||||
/*
|
||||
* This is move with zero-extend and sign-extend, respectively;
|
||||
* we don't have to think about 0xb6/0xbe, because this is
|
||||
* already handled in the conditional below.
|
||||
*/
|
||||
if (*op == 0xb7 || *op == 0xbf)
|
||||
operand_size_override = 2;
|
||||
}
|
||||
|
||||
*size = (*op & 1) ? operand_size_override : 1;
|
||||
}
|
||||
|
||||
const uint8_t *kmemcheck_opcode_get_primary(const uint8_t *op)
|
||||
{
|
||||
/* skip prefixes */
|
||||
while (opcode_is_prefix(*op))
|
||||
++op;
|
||||
if (opcode_is_rex_prefix(*op))
|
||||
++op;
|
||||
return op;
|
||||
}
|
||||
|
|
@ -0,0 +1,9 @@
|
|||
#ifndef ARCH__X86__MM__KMEMCHECK__OPCODE_H
|
||||
#define ARCH__X86__MM__KMEMCHECK__OPCODE_H
|
||||
|
||||
#include <linux/types.h>
|
||||
|
||||
void kmemcheck_opcode_decode(const uint8_t *op, unsigned int *size);
|
||||
const uint8_t *kmemcheck_opcode_get_primary(const uint8_t *op);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,22 @@
|
|||
#include <linux/mm.h>
|
||||
|
||||
#include <asm/pgtable.h>
|
||||
|
||||
#include "pte.h"
|
||||
|
||||
pte_t *kmemcheck_pte_lookup(unsigned long address)
|
||||
{
|
||||
pte_t *pte;
|
||||
unsigned int level;
|
||||
|
||||
pte = lookup_address(address, &level);
|
||||
if (!pte)
|
||||
return NULL;
|
||||
if (level != PG_LEVEL_4K)
|
||||
return NULL;
|
||||
if (!pte_hidden(*pte))
|
||||
return NULL;
|
||||
|
||||
return pte;
|
||||
}
|
||||
|
||||
|
|
@ -0,0 +1,10 @@
|
|||
#ifndef ARCH__X86__MM__KMEMCHECK__PTE_H
|
||||
#define ARCH__X86__MM__KMEMCHECK__PTE_H
|
||||
|
||||
#include <linux/mm.h>
|
||||
|
||||
#include <asm/pgtable.h>
|
||||
|
||||
pte_t *kmemcheck_pte_lookup(unsigned long address);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,153 @@
|
|||
#include <linux/kmemcheck.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mm.h>
|
||||
|
||||
#include <asm/page.h>
|
||||
#include <asm/pgtable.h>
|
||||
|
||||
#include "pte.h"
|
||||
#include "shadow.h"
|
||||
|
||||
/*
|
||||
* Return the shadow address for the given address. Returns NULL if the
|
||||
* address is not tracked.
|
||||
*
|
||||
* We need to be extremely careful not to follow any invalid pointers,
|
||||
* because this function can be called for *any* possible address.
|
||||
*/
|
||||
void *kmemcheck_shadow_lookup(unsigned long address)
|
||||
{
|
||||
pte_t *pte;
|
||||
struct page *page;
|
||||
|
||||
if (!virt_addr_valid(address))
|
||||
return NULL;
|
||||
|
||||
pte = kmemcheck_pte_lookup(address);
|
||||
if (!pte)
|
||||
return NULL;
|
||||
|
||||
page = virt_to_page(address);
|
||||
if (!page->shadow)
|
||||
return NULL;
|
||||
return page->shadow + (address & (PAGE_SIZE - 1));
|
||||
}
|
||||
|
||||
static void mark_shadow(void *address, unsigned int n,
|
||||
enum kmemcheck_shadow status)
|
||||
{
|
||||
unsigned long addr = (unsigned long) address;
|
||||
unsigned long last_addr = addr + n - 1;
|
||||
unsigned long page = addr & PAGE_MASK;
|
||||
unsigned long last_page = last_addr & PAGE_MASK;
|
||||
unsigned int first_n;
|
||||
void *shadow;
|
||||
|
||||
/* If the memory range crosses a page boundary, stop there. */
|
||||
if (page == last_page)
|
||||
first_n = n;
|
||||
else
|
||||
first_n = page + PAGE_SIZE - addr;
|
||||
|
||||
shadow = kmemcheck_shadow_lookup(addr);
|
||||
if (shadow)
|
||||
memset(shadow, status, first_n);
|
||||
|
||||
addr += first_n;
|
||||
n -= first_n;
|
||||
|
||||
/* Do full-page memset()s. */
|
||||
while (n >= PAGE_SIZE) {
|
||||
shadow = kmemcheck_shadow_lookup(addr);
|
||||
if (shadow)
|
||||
memset(shadow, status, PAGE_SIZE);
|
||||
|
||||
addr += PAGE_SIZE;
|
||||
n -= PAGE_SIZE;
|
||||
}
|
||||
|
||||
/* Do the remaining page, if any. */
|
||||
if (n > 0) {
|
||||
shadow = kmemcheck_shadow_lookup(addr);
|
||||
if (shadow)
|
||||
memset(shadow, status, n);
|
||||
}
|
||||
}
|
||||
|
||||
void kmemcheck_mark_unallocated(void *address, unsigned int n)
|
||||
{
|
||||
mark_shadow(address, n, KMEMCHECK_SHADOW_UNALLOCATED);
|
||||
}
|
||||
|
||||
void kmemcheck_mark_uninitialized(void *address, unsigned int n)
|
||||
{
|
||||
mark_shadow(address, n, KMEMCHECK_SHADOW_UNINITIALIZED);
|
||||
}
|
||||
|
||||
/*
|
||||
* Fill the shadow memory of the given address such that the memory at that
|
||||
* address is marked as being initialized.
|
||||
*/
|
||||
void kmemcheck_mark_initialized(void *address, unsigned int n)
|
||||
{
|
||||
mark_shadow(address, n, KMEMCHECK_SHADOW_INITIALIZED);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(kmemcheck_mark_initialized);
|
||||
|
||||
void kmemcheck_mark_freed(void *address, unsigned int n)
|
||||
{
|
||||
mark_shadow(address, n, KMEMCHECK_SHADOW_FREED);
|
||||
}
|
||||
|
||||
void kmemcheck_mark_unallocated_pages(struct page *p, unsigned int n)
|
||||
{
|
||||
unsigned int i;
|
||||
|
||||
for (i = 0; i < n; ++i)
|
||||
kmemcheck_mark_unallocated(page_address(&p[i]), PAGE_SIZE);
|
||||
}
|
||||
|
||||
void kmemcheck_mark_uninitialized_pages(struct page *p, unsigned int n)
|
||||
{
|
||||
unsigned int i;
|
||||
|
||||
for (i = 0; i < n; ++i)
|
||||
kmemcheck_mark_uninitialized(page_address(&p[i]), PAGE_SIZE);
|
||||
}
|
||||
|
||||
enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size)
|
||||
{
|
||||
uint8_t *x;
|
||||
unsigned int i;
|
||||
|
||||
x = shadow;
|
||||
|
||||
#ifdef CONFIG_KMEMCHECK_PARTIAL_OK
|
||||
/*
|
||||
* Make sure _some_ bytes are initialized. Gcc frequently generates
|
||||
* code to access neighboring bytes.
|
||||
*/
|
||||
for (i = 0; i < size; ++i) {
|
||||
if (x[i] == KMEMCHECK_SHADOW_INITIALIZED)
|
||||
return x[i];
|
||||
}
|
||||
#else
|
||||
/* All bytes must be initialized. */
|
||||
for (i = 0; i < size; ++i) {
|
||||
if (x[i] != KMEMCHECK_SHADOW_INITIALIZED)
|
||||
return x[i];
|
||||
}
|
||||
#endif
|
||||
|
||||
return x[0];
|
||||
}
|
||||
|
||||
void kmemcheck_shadow_set(void *shadow, unsigned int size)
|
||||
{
|
||||
uint8_t *x;
|
||||
unsigned int i;
|
||||
|
||||
x = shadow;
|
||||
for (i = 0; i < size; ++i)
|
||||
x[i] = KMEMCHECK_SHADOW_INITIALIZED;
|
||||
}
|
||||
|
|
@ -0,0 +1,16 @@
|
|||
#ifndef ARCH__X86__MM__KMEMCHECK__SHADOW_H
|
||||
#define ARCH__X86__MM__KMEMCHECK__SHADOW_H
|
||||
|
||||
enum kmemcheck_shadow {
|
||||
KMEMCHECK_SHADOW_UNALLOCATED,
|
||||
KMEMCHECK_SHADOW_UNINITIALIZED,
|
||||
KMEMCHECK_SHADOW_INITIALIZED,
|
||||
KMEMCHECK_SHADOW_FREED,
|
||||
};
|
||||
|
||||
void *kmemcheck_shadow_lookup(unsigned long address);
|
||||
|
||||
enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size);
|
||||
void kmemcheck_shadow_set(void *shadow, unsigned int size);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,17 @@
|
|||
#ifndef LINUX_KMEMCHECK_H
|
||||
#define LINUX_KMEMCHECK_H
|
||||
|
||||
#include <linux/mm_types.h>
|
||||
#include <linux/types.h>
|
||||
|
||||
#ifdef CONFIG_KMEMCHECK
|
||||
extern int kmemcheck_enabled;
|
||||
|
||||
int kmemcheck_show_addr(unsigned long address);
|
||||
int kmemcheck_hide_addr(unsigned long address);
|
||||
#else
|
||||
#define kmemcheck_enabled 0
|
||||
|
||||
#endif /* CONFIG_KMEMCHECK */
|
||||
|
||||
#endif /* LINUX_KMEMCHECK_H */
|
||||
|
|
@ -98,6 +98,14 @@ struct page {
|
|||
#ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS
|
||||
unsigned long debug_flags; /* Use atomic bitops on this */
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_KMEMCHECK
|
||||
/*
|
||||
* kmemcheck wants to track the status of each byte in a page; this
|
||||
* is a pointer to such a status block. NULL if not tracked.
|
||||
*/
|
||||
void *shadow;
|
||||
#endif
|
||||
};
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -65,6 +65,7 @@
|
|||
#include <linux/idr.h>
|
||||
#include <linux/ftrace.h>
|
||||
#include <linux/async.h>
|
||||
#include <linux/kmemcheck.h>
|
||||
#include <linux/kmemtrace.h>
|
||||
#include <trace/boot.h>
|
||||
|
||||
|
|
|
|||
|
|
@ -27,6 +27,7 @@
|
|||
#include <linux/security.h>
|
||||
#include <linux/ctype.h>
|
||||
#include <linux/utsname.h>
|
||||
#include <linux/kmemcheck.h>
|
||||
#include <linux/smp_lock.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/init.h>
|
||||
|
|
@ -959,6 +960,17 @@ static struct ctl_table kern_table[] = {
|
|||
.proc_handler = &proc_dointvec,
|
||||
},
|
||||
#endif
|
||||
#ifdef CONFIG_KMEMCHECK
|
||||
{
|
||||
.ctl_name = CTL_UNNUMBERED,
|
||||
.procname = "kmemcheck",
|
||||
.data = &kmemcheck_enabled,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = &proc_dointvec,
|
||||
},
|
||||
#endif
|
||||
|
||||
/*
|
||||
* NOTE: do not add new entries to this table unless you have read
|
||||
* Documentation/sysctl/ctl_unnumbered.txt
|
||||
|
|
|
|||
Loading…
Reference in New Issue