Commit 43beb5e8 authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracing: probe: Allocate traceprobe_parse_context from heap 

Instead of allocating traceprobe_parse_context on stack, allocate it
dynamically from heap (slab).

This change is likely intended to prevent potential stack overflow
issues, which can be a concern in the kernel environment where stack
space is limited.

Link: https://lore.kernel.org/all/175323425650.57270.280750740753792504.stgit@devnote2/



Reported-by: default avatarkernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202506240416.nZIhDXoO-lkp@intel.com/


Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 2f02a61d

kernel/trace/trace_eprobe.c

+8 −6
Original line number Diff line number Diff line
@@ -797,18 +797,20 @@ find_and_get_event(const char *system, const char *event_name) 


static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i)

{

	struct traceprobe_parse_context ctx = {

		.event = ep->event,

		.flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT,

	};

	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;

	int ret;



	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], &ctx);

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);

	if (!ctx)

		return -ENOMEM;

	ctx->event = ep->event;

	ctx->flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT;



	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], ctx);

	/* Handle symbols "@" */

	if (!ret)

		ret = traceprobe_update_arg(&ep->tp.args[i]);



	traceprobe_finish_parse(&ctx);

	return ret;

}

kernel/trace/trace_fprobe.c

+8 −5
Original line number Diff line number Diff line
@@ -1384,14 +1384,17 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], 


static int trace_fprobe_create_cb(int argc, const char *argv[])

{

	struct traceprobe_parse_context ctx = {

		.flags = TPARG_FL_KERNEL | TPARG_FL_FPROBE,

	};

	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;

	int ret;



	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);

	if (!ctx)

		return -ENOMEM;



	ctx->flags = TPARG_FL_KERNEL | TPARG_FL_FPROBE,



	trace_probe_log_init("trace_fprobe", argc, argv);

	ret = trace_fprobe_create_internal(argc, argv, &ctx);

	traceprobe_finish_parse(&ctx);

	ret = trace_fprobe_create_internal(argc, argv, ctx);

	trace_probe_log_clear();

	return ret;

}

kernel/trace/trace_kprobe.c

+7 −3
Original line number Diff line number Diff line
@@ -1065,14 +1065,18 @@ static int trace_kprobe_create_internal(int argc, const char *argv[], 


static int trace_kprobe_create_cb(int argc, const char *argv[])

{

	struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL };

	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;

	int ret;



	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);

	if (!ctx)

		return -ENOMEM;

	ctx->flags = TPARG_FL_KERNEL;



	trace_probe_log_init("trace_kprobe", argc, argv);



	ret = trace_kprobe_create_internal(argc, argv, &ctx);

	ret = trace_kprobe_create_internal(argc, argv, ctx);



	traceprobe_finish_parse(&ctx);

	trace_probe_log_clear();

	return ret;

}

kernel/trace/trace_probe.h

+9 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 


#include <linux/bitops.h>

#include <linux/btf.h>

#include <linux/cleanup.h>

#include <linux/kprobes.h>

#include <linux/limits.h>

#include <linux/perf_event.h>
@@ -439,6 +440,14 @@ extern void traceprobe_free_probe_arg(struct probe_arg *arg); 
 * this MUST be called for clean up the context and return a resource.

 */

void traceprobe_finish_parse(struct traceprobe_parse_context *ctx);

static inline void traceprobe_free_parse_ctx(struct traceprobe_parse_context *ctx)

{

	traceprobe_finish_parse(ctx);

	kfree(ctx);

}



DEFINE_FREE(traceprobe_parse_context, struct traceprobe_parse_context *,

	if (_T) traceprobe_free_parse_ctx(_T))



extern int traceprobe_split_symbol_offset(char *symbol, long *offset);

int traceprobe_parse_event_name(const char **pevent, const char **pgroup,

kernel/trace/trace_uprobe.c

+8 −5
Original line number Diff line number Diff line
@@ -695,13 +695,16 @@ static int __trace_uprobe_create(int argc, const char **argv) 


	/* parse arguments */

	for (i = 0; i < argc; i++) {

		struct traceprobe_parse_context ctx = {

			.flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER,

		};

		struct traceprobe_parse_context *ctx __free(traceprobe_parse_context)

			= kzalloc(sizeof(*ctx), GFP_KERNEL);



		if (!ctx) {

			ret = -ENOMEM;

			goto error;

		}

		ctx->flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER;

		trace_probe_log_set_index(i + 2);

		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], &ctx);

		traceprobe_finish_parse(&ctx);

		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], ctx);

		if (ret)

			goto error;

	}