* Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*/
+#include <wrapper/compiler_attributes.h>
#include <wrapper/uaccess.h>
-#include <wrapper/frame.h>
+#include <wrapper/objtool.h>
#include <wrapper/types.h>
#include <linux/swab.h>
#include <lttng-filter.h>
#include <lttng-string-utils.h>
+#include <probes/lttng-probe-user.h>
LTTNG_STACK_FRAME_NON_STANDARD(lttng_filter_interpret_bytecode);
* to handle user-space read.
*/
static
-char get_char(struct estack_entry *reg, size_t offset)
+char get_char(const struct estack_entry *reg, size_t offset)
{
if (unlikely(offset >= reg->u.s.seq_len))
return '\0';
int stack_star_glob_match(struct estack *stack, int top, const char *cmp_type)
{
bool has_user = false;
- mm_segment_t old_fs;
int result;
struct estack_entry *pattern_reg;
struct estack_entry *candidate_reg;
+ /* Disable the page fault handler when reading from userspace. */
if (estack_bx(stack, top)->u.s.user
|| estack_ax(stack, top)->u.s.user) {
has_user = true;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
pagefault_disable();
}
/* Perform the match operation. */
result = !strutils_star_glob_match_char_cb(get_char_at_cb,
pattern_reg, get_char_at_cb, candidate_reg);
- if (has_user) {
+ if (has_user)
pagefault_enable();
- set_fs(old_fs);
- }
return result;
}
{
size_t offset_bx = 0, offset_ax = 0;
int diff, has_user = 0;
- mm_segment_t old_fs;
if (estack_bx(stack, top)->u.s.user
|| estack_ax(stack, top)->u.s.user) {
has_user = 1;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
pagefault_disable();
}
offset_bx++;
offset_ax++;
}
- if (has_user) {
+ if (has_user)
pagefault_enable();
- set_fs(old_fs);
- }
+
return diff;
}
ptr->u.u64 = v.s64; /* Cast. */
ptr->ptr = &ptr->u.u64;
}
+ ptr->rev_bo = field->type.u.basic.integer.reverse_byte_order;
+ ptr->user = field->type.u.basic.integer.user;
break;
case atype_enum:
{
ptr->u.u64 = v.s64; /* Cast. */
ptr->ptr = &ptr->u.u64;
}
+ ptr->rev_bo = itype->reverse_byte_order;
+ ptr->user = itype->user;
break;
}
case atype_array:
ptr->object_type = OBJECT_TYPE_STRING;
ctx_field->get_value(ctx_field, lttng_probe_ctx, &v);
ptr->ptr = v.str;
+ ptr->user = field->type.u.array.elem_type.u.basic.integer.user;
break;
case atype_sequence:
if (field->type.u.sequence.elem_type.atype != atype_integer) {
ptr->object_type = OBJECT_TYPE_STRING;
ctx_field->get_value(ctx_field, lttng_probe_ctx, &v);
ptr->ptr = v.str;
+ ptr->user = field->type.u.sequence.elem_type.u.basic.integer.user;
break;
case atype_array_bitfield:
printk(KERN_WARNING "Bitfield array type is not supported.\n");
ptr->object_type = OBJECT_TYPE_STRING;
ctx_field->get_value(ctx_field, lttng_probe_ctx, &v);
ptr->ptr = v.str;
+ ptr->user = field->type.u.basic.string.user;
break;
case atype_struct:
printk(KERN_WARNING "Structure type cannot be loaded.\n");
stack_top->u.ptr.ptr = ptr;
stack_top->u.ptr.object_type = gid->elem.type;
stack_top->u.ptr.rev_bo = gid->elem.rev_bo;
+ stack_top->u.ptr.user = gid->elem.user;
/* field is only used for types nested within variants. */
stack_top->u.ptr.field = NULL;
break;
stack_top->u.ptr.ptr = ptr;
stack_top->u.ptr.object_type = gid->elem.type;
stack_top->u.ptr.rev_bo = gid->elem.rev_bo;
+ stack_top->u.ptr.user = gid->elem.user;
/* field is only used for types nested within variants. */
stack_top->u.ptr.field = NULL;
break;
}
break;
case LOAD_ROOT_CONTEXT:
- case LOAD_ROOT_APP_CONTEXT: /* Fall-through */
+ lttng_fallthrough;
+ case LOAD_ROOT_APP_CONTEXT:
{
ret = context_get_index(lttng_probe_ctx,
&stack_top->u.ptr,
stack_top->u.ptr.type = LOAD_OBJECT;
/* field is only used for types nested within variants. */
stack_top->u.ptr.field = NULL;
+ stack_top->u.ptr.rev_bo = gid->elem.rev_bo;
+ stack_top->u.ptr.user = gid->elem.user;
break;
}
return 0;
switch (stack_top->u.ptr.object_type) {
case OBJECT_TYPE_S8:
dbg_printk("op load field s8\n");
- stack_top->u.v = *(int8_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&stack_top->u.v, (int8_t __user *) stack_top->u.ptr.ptr, sizeof(int8_t)))
+ stack_top->u.v = 0;
+ } else {
+ stack_top->u.v = *(int8_t *) stack_top->u.ptr.ptr;
+ }
break;
case OBJECT_TYPE_S16:
{
int16_t tmp;
dbg_printk("op load field s16\n");
- tmp = *(int16_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (int16_t __user *) stack_top->u.ptr.ptr, sizeof(int16_t)))
+ tmp = 0;
+ } else {
+ tmp = *(int16_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab16s(&tmp);
stack_top->u.v = tmp;
int32_t tmp;
dbg_printk("op load field s32\n");
- tmp = *(int32_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (int32_t __user *) stack_top->u.ptr.ptr, sizeof(int32_t)))
+ tmp = 0;
+ } else {
+ tmp = *(int32_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab32s(&tmp);
stack_top->u.v = tmp;
int64_t tmp;
dbg_printk("op load field s64\n");
- tmp = *(int64_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (int64_t __user *) stack_top->u.ptr.ptr, sizeof(int64_t)))
+ tmp = 0;
+ } else {
+ tmp = *(int64_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab64s(&tmp);
stack_top->u.v = tmp;
}
case OBJECT_TYPE_U8:
dbg_printk("op load field u8\n");
- stack_top->u.v = *(uint8_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&stack_top->u.v, (uint8_t __user *) stack_top->u.ptr.ptr, sizeof(uint8_t)))
+ stack_top->u.v = 0;
+ } else {
+ stack_top->u.v = *(uint8_t *) stack_top->u.ptr.ptr;
+ }
break;
case OBJECT_TYPE_U16:
{
uint16_t tmp;
dbg_printk("op load field s16\n");
- tmp = *(uint16_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (uint16_t __user *) stack_top->u.ptr.ptr, sizeof(uint16_t)))
+ tmp = 0;
+ } else {
+ tmp = *(uint16_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab16s(&tmp);
stack_top->u.v = tmp;
uint32_t tmp;
dbg_printk("op load field u32\n");
- tmp = *(uint32_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (uint32_t __user *) stack_top->u.ptr.ptr, sizeof(uint32_t)))
+ tmp = 0;
+ } else {
+ tmp = *(uint32_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab32s(&tmp);
stack_top->u.v = tmp;
uint64_t tmp;
dbg_printk("op load field u64\n");
- tmp = *(uint64_t *) stack_top->u.ptr.ptr;
+ if (stack_top->u.ptr.user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, (uint64_t __user *) stack_top->u.ptr.ptr, sizeof(uint64_t)))
+ tmp = 0;
+ } else {
+ tmp = *(uint64_t *) stack_top->u.ptr.ptr;
+ }
if (stack_top->u.ptr.rev_bo)
__swab64s(&tmp);
stack_top->u.v = tmp;
}
case OBJECT_TYPE_STRING:
{
- const char *str;
+ dbg_printk("op load field string: user=%d\n", stack_top->u.ptr.user);
+ if (stack_top->u.ptr.user) {
+ const char __user *user_str = (const char __user *) stack_top->u.ptr.ptr;
- dbg_printk("op load field string\n");
- str = (const char *) stack_top->u.ptr.ptr;
- stack_top->u.s.str = str;
- if (unlikely(!stack_top->u.s.str)) {
- dbg_printk("Filter warning: loading a NULL string.\n");
- ret = -EINVAL;
- goto end;
+ stack_top->u.s.user_str = user_str;
+ if (unlikely(!stack_top->u.s.user_str)) {
+ dbg_printk("Bytecode warning: loading a NULL user string.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ stack_top->u.s.user = 1;
+ } else {
+ const char *str = (const char *) stack_top->u.ptr.ptr;
+
+ stack_top->u.s.str = str;
+ if (unlikely(!stack_top->u.s.str)) {
+ dbg_printk("Bytecode warning: loading a NULL string.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ stack_top->u.s.user = 0;
}
stack_top->u.s.seq_len = LTTNG_SIZE_MAX;
- stack_top->u.s.literal_type =
- ESTACK_STRING_LITERAL_TYPE_NONE;
+ stack_top->u.s.literal_type = ESTACK_STRING_LITERAL_TYPE_NONE;
break;
}
case OBJECT_TYPE_STRING_SEQUENCE:
dbg_printk("op load field string sequence\n");
ptr = stack_top->u.ptr.ptr;
stack_top->u.s.seq_len = *(unsigned long *) ptr;
- stack_top->u.s.str = *(const char **) (ptr + sizeof(unsigned long));
- if (unlikely(!stack_top->u.s.str)) {
- dbg_printk("Filter warning: loading a NULL sequence.\n");
- ret = -EINVAL;
- goto end;
+ if (stack_top->u.ptr.user) {
+ stack_top->u.s.user_str = *(const char __user **) (ptr + sizeof(unsigned long));
+ if (unlikely(!stack_top->u.s.user_str)) {
+ dbg_printk("Bytecode warning: loading a NULL user sequence.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ stack_top->u.s.user = 1;
+ } else {
+ stack_top->u.s.str = *(const char **) (ptr + sizeof(unsigned long));
+ if (unlikely(!stack_top->u.s.str)) {
+ dbg_printk("Bytecode warning: loading a NULL sequence.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ stack_top->u.s.user = 0;
}
- stack_top->u.s.literal_type =
- ESTACK_STRING_LITERAL_TYPE_NONE;
+ stack_top->u.s.literal_type = ESTACK_STRING_LITERAL_TYPE_NONE;
break;
}
case OBJECT_TYPE_DYNAMIC:
return ret;
}
+#ifdef DEBUG
+
+#define DBG_USER_STR_CUTOFF 32
+
+/*
+ * In debug mode, print user string (truncated, if necessary).
+ */
+static inline
+void dbg_load_ref_user_str_printk(const struct estack_entry *user_str_reg)
+{
+ size_t pos = 0;
+ char last_char;
+ char user_str[DBG_USER_STR_CUTOFF];
+
+ pagefault_disable();
+ do {
+ last_char = get_char(user_str_reg, pos);
+ user_str[pos] = last_char;
+ pos++;
+ } while (last_char != '\0' && pos < sizeof(user_str));
+ pagefault_enable();
+
+ user_str[sizeof(user_str) - 1] = '\0';
+ dbg_printk("load field ref user string: '%s%s'\n", user_str,
+ last_char != '\0' ? "[...]" : "");
+}
+#else
+static inline
+void dbg_load_ref_user_str_printk(const struct estack_entry *user_str_reg)
+{
+}
+#endif
+
/*
* Return 0 (discard), or raise the 0x1 flag (log event).
* Currently, other flags are kept for future extensions and have no
estack_push(stack, top, ax, bx);
estack_ax(stack, top)->u.s.user_str =
*(const char * const *) &filter_stack_data[ref->offset];
- if (unlikely(!estack_ax(stack, top)->u.s.str)) {
+ if (unlikely(!estack_ax(stack, top)->u.s.user_str)) {
dbg_printk("Filter warning: loading a NULL string.\n");
ret = -EINVAL;
goto end;
estack_ax(stack, top)->u.s.literal_type =
ESTACK_STRING_LITERAL_TYPE_NONE;
estack_ax(stack, top)->u.s.user = 1;
- dbg_printk("ref load string %s\n", estack_ax(stack, top)->u.s.str);
+ dbg_load_ref_user_str_printk(estack_ax(stack, top));
next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
PO;
}
estack_ax(stack, top)->u.s.user_str =
*(const char **) (&filter_stack_data[ref->offset
+ sizeof(unsigned long)]);
- if (unlikely(!estack_ax(stack, top)->u.s.str)) {
+ if (unlikely(!estack_ax(stack, top)->u.s.user_str)) {
dbg_printk("Filter warning: loading a NULL sequence.\n");
ret = -EINVAL;
goto end;
estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
estack_ax(stack, top)->u.s.literal_type =
ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 0;
next_pc += sizeof(struct load_op);
PO;
}
}
estack_ax(stack, top)->u.s.literal_type =
ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 0;
next_pc += sizeof(struct load_op);
PO;
}
projects / lttng-modules.git / blobdiff