fix: net: skb: introduce kfree_skb_reason() (v5.17)
[lttng-modules.git] / lttng-filter-interpreter.c
index 21169f01fe3ef22fc0f996246d898564366676b8..d9dc6195f2f78cf1d683b48e046be01e2383f124 100644 (file)
@@ -7,8 +7,9 @@
  * 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>
 
@@ -22,7 +23,7 @@ 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';
@@ -419,7 +420,8 @@ static int dynamic_get_index(struct lttng_probe_ctx *lttng_probe_ctx,
                }
                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,
@@ -593,6 +595,39 @@ end:
        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
@@ -1313,7 +1348,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
                        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;
@@ -1322,7 +1357,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
                        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;
                }
@@ -1340,7 +1375,7 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
                        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;
This page took 0.024333 seconds and 4 git commands to generate.