| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20211014014445.5734-1-xiehuan09@gmail.com>
Date: Thu, 14 Oct 2021 09:44:45 +0800
From: Jeff Xie <xiehuan09@...il.com>
To: rostedt@...dmis.org, mingo@...hat.com
Cc: chenhuacai@...nel.org, linux-kernel@...r.kernel.org,
Jeff Xie <xiehuan09@...il.com>
Subject: [PATCH] trace: Add trace any kernel object
Introduce a method based on function tracer and kprobe event
to trace any object in the linux kernel.
Usage:
When using the kprobe event, only need to enable trace_object,
we can trace any function argument or the return value. When
the object passes through a function, it can be traced.
For example:
For the function bio_add_page, we can trace the first argument:
int bio_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int offset)
#cd /sys/kernel/debug/tracing
#echo 1 > ./trace_object
#echo 'p bio_add_page arg1=$arg1' > kprobe_events
#echo 1 > ./events/kprobes/p_bio_add_page_0/enable
#sync
#cat ./trace
# tracer: nop
#
# entries-in-buffer/entries-written: 367/367 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / _-=> migrate-disable
# |||| / delay
# TASK-PID CPU# ||||| TIMESTAMP FUNCTION
# | | | ||||| | |
kworker/u8:5-89 [000] ..... 60.310385: p_bio_add_page_0: (bio_add_page+0x0/0x90) arg1=0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310386: bio_add_page <-ext4_bio_write_page object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310387: __bio_try_merge_page <-bio_add_page object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310387: __bio_add_page <-bio_add_page object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310389: submit_bio <-ext4_io_submit object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310389: submit_bio <-ext4_io_submit object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310389: submit_bio_noacct <-ext4_io_submit object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310389: submit_bio_checks <-submit_bio_noacct object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310390: __cond_resched <-submit_bio_checks object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310390: rcu_all_qs <-__cond_resched object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310390: should_fail_bio <-submit_bio_checks object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310391: blk_mq_submit_bio <-submit_bio_noacct object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310392: blk_attempt_plug_merge <-blk_mq_submit_bio object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310392: __blk_mq_sched_bio_merge <-blk_mq_submit_bio object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310392: __blk_mq_alloc_request <-blk_mq_submit_bio object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310393: blk_mq_get_tag <-__blk_mq_alloc_request object:0xffff888102bde780
kworker/u8:5-89 [000] ..... 60.310394: blk_account_io_start <-blk_mq_submit_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311264: bio_advance <-blk_update_request object:0xffff888102bde780
<idle>-0 [000] d.... 60.311265: bio_endio <-blk_update_request object:0xffff888102bde780
<idle>-0 [000] d.... 60.311265: ext4_end_bio <-blk_update_request object:0xffff888102bde780
<idle>-0 [000] d.... 60.311266: ext4_finish_bio <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311274: bio_put <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311274: bio_free <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311274: bio_free <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311274: bvec_free <-bio_free object:0xffff888102bde780
<idle>-0 [000] d.... 60.311275: mempool_free <-bio_free object:0xffff888102bde780
<idle>-0 [000] d.... 60.311275: mempool_free_slab <-bio_free object:0xffff888102bde780
<idle>-0 [000] d.... 60.311275: mempool_free <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311275: mempool_free_slab <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311275: kmem_cache_free <-ext4_end_bio object:0xffff888102bde780
<idle>-0 [000] d.... 60.311276: kmem_cache_free <-ext4_end_bio object:0xffff888102bde780
...
Signed-off-by: Jeff Xie <xiehuan09@...il.com>
---
include/linux/ftrace.h | 6 ++
kernel/trace/Kconfig | 7 ++
kernel/trace/Makefile | 1 +
kernel/trace/trace.c | 69 +++++++++++++++++++
kernel/trace/trace.h | 2 +
kernel/trace/trace_entries.h | 17 +++++
kernel/trace/trace_kprobe.c | 6 ++
kernel/trace/trace_object.c | 128 +++++++++++++++++++++++++++++++++++
kernel/trace/trace_output.c | 40 +++++++++++
9 files changed, 276 insertions(+)
create mode 100644 kernel/trace/trace_object.c
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 832e65f06754..2e097a5fa462 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -1078,4 +1078,10 @@ unsigned long arch_syscall_addr(int nr);
#endif /* CONFIG_FTRACE_SYSCALLS */
+#ifdef CONFIG_TRACE_OBJECT
+int init_trace_object(void);
+int exit_trace_object(void);
+void set_trace_object(void *obj);
+#endif
+
#endif /* _LINUX_FTRACE_H */
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 420ff4bc67fd..d302a0f085f9 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -237,6 +237,13 @@ config FUNCTION_PROFILER
If in doubt, say N.
+config TRACE_OBJECT
+ bool "Trace kernel object"
+ depends on FUNCTION_TRACER
+ default y
+ help
+ This help kernel developer to trace any kernel object.
+
config STACK_TRACER
bool "Trace max stack"
depends on HAVE_FUNCTION_TRACER
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 6de5d4d63165..6d9e78a488aa 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -66,6 +66,7 @@ obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += fgraph.o
+obj-$(CONFIG_TRACE_OBJECT) += trace_object.o
ifeq ($(CONFIG_BLOCK),y)
obj-$(CONFIG_EVENT_TRACING) += blktrace.o
endif
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7896d30d90f7..8069562bfde1 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -9412,6 +9412,70 @@ static __init void create_trace_instances(struct dentry *d_tracer)
mutex_unlock(&event_mutex);
}
+#if defined(CONFIG_TRACE_OBJECT)
+
+static DEFINE_MUTEX(trace_object_lock);
+static int trace_object_enabled __read_mostly;
+
+static ssize_t
+trace_object_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ int r;
+
+ r = sprintf(buf, "%u\n", trace_object_enabled);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+trace_object_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ val = !!val;
+
+ mutex_lock(&trace_object_lock);
+ if (trace_object_enabled ^ val) {
+ if (val) {
+ ret = init_trace_object();
+ if (ret < 0) {
+ cnt = ret;
+ goto out;
+ }
+
+ trace_object_enabled = 1;
+ } else {
+ ret = exit_trace_object();
+ if (ret < 0) {
+ cnt = ret;
+ goto out;
+ }
+
+ trace_object_enabled = 0;
+ }
+ }
+out:
+ mutex_unlock(&trace_object_lock);
+ *ppos += cnt;
+ return cnt;
+}
+
+static const struct file_operations trace_object_fops = {
+ .open = tracing_open_generic,
+ .read = trace_object_read,
+ .write = trace_object_write,
+ .llseek = default_llseek,
+};
+
+#endif
+
static void
init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
@@ -9477,6 +9541,11 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_maxlat_file(tr, d_tracer);
#endif
+#if defined(CONFIG_TRACE_OBJECT)
+ trace_create_file("trace_object", 0644, d_tracer, tr,
+ &trace_object_fops);
+#endif
+
if (ftrace_create_function_files(tr, d_tracer))
MEM_FAIL(1, "Could not allocate function filter files");
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b7c0f8e160fb..bf6bcaa24e1a 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -49,6 +49,7 @@ enum trace_type {
TRACE_TIMERLAT,
TRACE_RAW_DATA,
TRACE_FUNC_REPEATS,
+ TRACE_OBJECT,
__TRACE_LAST_TYPE,
};
@@ -460,6 +461,7 @@ extern void __ftrace_bad_type(void);
TRACE_GRAPH_RET); \
IF_ASSIGN(var, ent, struct func_repeats_entry, \
TRACE_FUNC_REPEATS); \
+ IF_ASSIGN(var, ent, struct trace_object_entry, TRACE_OBJECT);\
__ftrace_bad_type(); \
} while (0)
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index cd41e863b51c..27bababc0ed4 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -401,3 +401,20 @@ FTRACE_ENTRY(timerlat, timerlat_entry,
__entry->context,
__entry->timer_latency)
);
+
+/*
+ * trace object entry:
+ */
+FTRACE_ENTRY(object, trace_object_entry,
+
+ TRACE_OBJECT,
+
+ F_STRUCT(
+ __field( unsigned long, ip )
+ __field( unsigned long, parent_ip )
+ __field( unsigned long, object )
+ ),
+
+ F_printk(" %ps <-- %ps object:%lx\n",
+ (void *)__entry->ip, (void *)__entry->parent_ip, __entry->object)
+);
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 3a64ba4bbad6..0d46670702d9 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1341,6 +1341,9 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
break;
case FETCH_OP_RETVAL:
val = regs_return_value(regs);
+#ifdef CONFIG_TRACE_OBJECT
+ set_trace_object((void *)val);
+#endif
break;
case FETCH_OP_IMM:
val = code->immediate;
@@ -1354,6 +1357,9 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
+#ifdef CONFIG_TRACE_OBJECT
+ set_trace_object((void *)val);
+#endif
break;
#endif
case FETCH_NOP_SYMBOL: /* Ignore a place holder */
diff --git a/kernel/trace/trace_object.c b/kernel/trace/trace_object.c
new file mode 100644
index 000000000000..eb8edfebecee
--- /dev/null
+++ b/kernel/trace/trace_object.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * trace any object
+ * Copyright (C) 2021 Jeff Xie <xiehuan09@...il.com>
+ */
+
+#define pr_fmt(fmt) "trace_object: " fmt
+
+#include "trace_output.h"
+
+static DEFINE_PER_CPU(atomic_t, trace_object_event_disable);
+static DEFINE_MUTEX(object_mutex_lock);
+static struct trace_event_file event_trace_file;
+
+#define MAX_TRACE_OBJ_NUM 1024
+static unsigned long *global_trace_obj;
+static int global_trace_count;
+static const int max_args_num = 6;
+
+void set_trace_object(void *obj)
+{
+ int i;
+
+ if (!obj || global_trace_count == MAX_TRACE_OBJ_NUM)
+ goto out;
+
+ for (i = 0; i < global_trace_count; i++) {
+ if (global_trace_obj[i] == (unsigned long)obj)
+ goto out;
+ }
+ mutex_lock(&object_mutex_lock);
+
+ global_trace_obj[global_trace_count++] = (unsigned long)obj;
+
+ mutex_unlock(&object_mutex_lock);
+out:
+ return;
+}
+
+static void submit_trace_object(unsigned long ip, unsigned long parent_ip,
+ unsigned long object)
+{
+
+ struct trace_buffer *buffer;
+ struct ring_buffer_event *event;
+ struct trace_object_entry *entry;
+ int pc;
+
+ pc = preempt_count();
+ event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file,
+ TRACE_OBJECT, sizeof(*entry), pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->parent_ip = parent_ip;
+ entry->object = object;
+
+ event_trigger_unlock_commit(&event_trace_file, buffer, event,
+ entry, pc);
+}
+
+static void
+trace_object_events_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct ftrace_regs *fregs)
+{
+ struct pt_regs *pt_regs = ftrace_get_regs(fregs);
+ unsigned long object;
+ long disabled;
+ int cpu, n, i;
+
+ preempt_disable_notrace();
+
+ cpu = raw_smp_processor_id();
+ disabled = atomic_inc_return(&per_cpu(trace_object_event_disable, cpu));
+
+ if (disabled != 1)
+ goto out;
+
+ if (!global_trace_obj[0])
+ goto out;
+
+ for (n = 0; n < max_args_num; n++) {
+ object = regs_get_kernel_argument(pt_regs, n);
+ for (i = 0; i < global_trace_count; i++) {
+ if (object == global_trace_obj[i])
+ submit_trace_object(ip, parent_ip, object);
+ }
+ }
+out:
+ atomic_dec(&per_cpu(trace_object_event_disable, cpu));
+ preempt_enable_notrace();
+}
+
+static struct ftrace_ops trace_ops = {
+ .func = trace_object_events_call,
+ .flags = FTRACE_OPS_FL_SAVE_REGS,
+};
+
+int init_trace_object(void)
+{
+ int ret;
+
+ event_trace_file.tr = top_trace_array();
+ if (WARN_ON(!event_trace_file.tr))
+ return -1;
+
+ global_trace_obj = kzalloc(sizeof(unsigned long) * MAX_TRACE_OBJ_NUM,
+ GFP_KERNEL);
+ if (!global_trace_obj)
+ return -ENOMEM;
+
+ ret = register_ftrace_function(&trace_ops);
+
+ return ret;
+}
+
+int exit_trace_object(void)
+{
+ int ret;
+
+ ret = unregister_ftrace_function(&trace_ops);
+
+ kfree(global_trace_obj);
+ return ret;
+}
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index c2ca40e8595b..21a9c8737929 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -1552,6 +1552,45 @@ static struct trace_event trace_func_repeats_event = {
.funcs = &trace_func_repeats_funcs,
};
+/* TRACE_OBJECT */
+static enum print_line_t trace_object_print(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct trace_object_entry *field;
+ struct trace_seq *s = &iter->seq;
+
+ trace_assign_type(field, iter->ent);
+ print_fn_trace(s, field->ip, field->parent_ip, flags);
+ trace_seq_printf(s, " object:0x%lx", field->object);
+ trace_seq_putc(s, '\n');
+
+ return trace_handle_return(s);
+}
+
+static enum print_line_t trace_object_raw(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct trace_object_entry *field;
+
+ trace_assign_type(field, iter->ent);
+
+ trace_seq_printf(&iter->seq, "%lx %lx\n",
+ field->ip,
+ field->parent_ip);
+
+ return trace_handle_return(&iter->seq);
+}
+
+static struct trace_event_functions trace_object_funcs = {
+ .trace = trace_object_print,
+ .raw = trace_object_raw,
+};
+
+static struct trace_event trace_object_event = {
+ .type = TRACE_OBJECT,
+ .funcs = &trace_object_funcs,
+};
+
static struct trace_event *events[] __initdata = {
&trace_fn_event,
&trace_ctx_event,
@@ -1566,6 +1605,7 @@ static struct trace_event *events[] __initdata = {
&trace_timerlat_event,
&trace_raw_data_event,
&trace_func_repeats_event,
+ &trace_object_event,
NULL
};
--
2.25.1
Powered by blists - more mailing lists