Commit 8fe4dc4f authored by Menglong Dong's avatar Menglong Dong Committed by Alexei Starovoitov
Browse files

bpf: change prototype of bpf_session_{cookie,is_return} 



Add the function argument of "void *ctx" to bpf_session_cookie() and
bpf_session_is_return(), which is a preparation of the next patch.

The two kfunc is seldom used now, so it will not introduce much effect
to change their function prototype.

Signed-off-by: default avatarMenglong Dong <dongml2@chinatelecom.cn>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20260124062008.8657-4-dongml2@chinatelecom.cn


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent f1b56b3c

kernel/bpf/verifier.c

+5 −1
Original line number Diff line number Diff line
@@ -12484,6 +12484,7 @@ enum special_kfunc_type { 
	KF_bpf_arena_alloc_pages,

	KF_bpf_arena_free_pages,

	KF_bpf_arena_reserve_pages,

	KF_bpf_session_is_return,

};









BTF_ID_LIST(special_kfunc_list)








@@ -12561,6 +12562,7 @@ BTF_ID(func, bpf_task_work_schedule_resume)







BTF_ID(func, bpf_arena_alloc_pages)









BTF_ID(func, bpf_arena_free_pages)









BTF_ID(func, bpf_arena_reserve_pages)









BTF_ID(func, bpf_session_is_return)

















static bool is_task_work_add_kfunc(u32 func_id)









{








@@ -12615,7 +12617,9 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,







	struct bpf_reg_state *reg = &regs[regno];









	bool arg_mem_size = false;

















	if (meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx])









	if (meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx] ||









	    meta->func_id == special_kfunc_list[KF_bpf_session_is_return] ||









	    meta->func_id == special_kfunc_list[KF_bpf_session_cookie])









		return KF_ARG_PTR_TO_CTX;

















	if (argno + 1 < nargs &&
































kernel/trace/bpf_trace.c



+2
−2






























Original line number
Diff line number
Diff line







@@ -3323,7 +3323,7 @@ static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx)

















__bpf_kfunc_start_defs();



















__bpf_kfunc bool bpf_session_is_return(void)









__bpf_kfunc bool bpf_session_is_return(void *ctx)









{









	struct bpf_session_run_ctx *session_ctx;


















@@ -3331,7 +3331,7 @@ __bpf_kfunc bool bpf_session_is_return(void)







	return session_ctx->is_return;









}



















__bpf_kfunc __u64 *bpf_session_cookie(void)









__bpf_kfunc __u64 *bpf_session_cookie(void *ctx)









{









	struct bpf_session_run_ctx *session_ctx;










































tools/testing/selftests/bpf/bpf_kfuncs.h



+0
−3






























Original line number
Diff line number
Diff line







@@ -79,9 +79,6 @@ extern int bpf_verify_pkcs7_signature(struct bpf_dynptr *data_ptr,







				      struct bpf_dynptr *sig_ptr,









				      struct bpf_key *trusted_keyring) __ksym;



















extern bool bpf_session_is_return(void) __ksym __weak;









extern __u64 *bpf_session_cookie(void) __ksym __weak;



















struct dentry;









/* Description









 *  Returns xattr of a dentry
































tools/testing/selftests/bpf/progs/kprobe_multi_session_cookie.c



+7
−8






























Original line number
Diff line number
Diff line









// SPDX-License-Identifier: GPL-2.0









#include <linux/bpf.h>









#include <vmlinux.h>









#include <bpf/bpf_helpers.h>









#include <bpf/bpf_tracing.h>









#include <stdbool.h>









#include "bpf_kfuncs.h"



















char _license[] SEC("license") = "GPL";


















@@ -23,16 +22,16 @@ int BPF_PROG(trigger)







	return 0;









}



















static int check_cookie(__u64 val, __u64 *result)









static int check_cookie(struct pt_regs *ctx, __u64 val, __u64 *result)









{









	__u64 *cookie;



















	if (bpf_get_current_pid_tgid() >> 32 != pid)









		return 1;



















	cookie = bpf_session_cookie();









	cookie = bpf_session_cookie(ctx);



















	if (bpf_session_is_return())









	if (bpf_session_is_return(ctx))









		*result = *cookie == val ? val : 0;









	else









		*cookie = val;








@@ -42,17 +41,17 @@ static int check_cookie(__u64 val, __u64 *result)







SEC("kprobe.session/bpf_fentry_test1")









int test_kprobe_1(struct pt_regs *ctx)









{









	return check_cookie(1, &test_kprobe_1_result);









	return check_cookie(ctx, 1, &test_kprobe_1_result);









}



















SEC("kprobe.session/bpf_fentry_test1")









int test_kprobe_2(struct pt_regs *ctx)









{









	return check_cookie(2, &test_kprobe_2_result);









	return check_cookie(ctx, 2, &test_kprobe_2_result);









}



















SEC("kprobe.session/bpf_fentry_test1")









int test_kprobe_3(struct pt_regs *ctx)









{









	return check_cookie(3, &test_kprobe_3_result);









	return check_cookie(ctx, 3, &test_kprobe_3_result);









}
























tools/testing/selftests/bpf/progs/uprobe_multi_session.c



+3
−4






























Original line number
Diff line number
Diff line









// SPDX-License-Identifier: GPL-2.0









#include <linux/bpf.h>









#include <vmlinux.h>









#include <bpf/bpf_helpers.h>









#include <bpf/bpf_tracing.h>









#include <stdbool.h>









#include "bpf_kfuncs.h"









#include "bpf_misc.h"



















char _license[] SEC("license") = "GPL";








@@ -51,7 +50,7 @@ static int uprobe_multi_check(void *ctx, bool is_return)







SEC("uprobe.session//proc/self/exe:uprobe_multi_func_*")









int uprobe(struct pt_regs *ctx)









{









	return uprobe_multi_check(ctx, bpf_session_is_return());









	return uprobe_multi_check(ctx, bpf_session_is_return(ctx));









}



















static __always_inline bool verify_sleepable_user_copy(void)








@@ -67,5 +66,5 @@ int uprobe_sleepable(struct pt_regs *ctx)







{









	if (verify_sleepable_user_copy())









		uprobe_multi_sleep_result++;









	return uprobe_multi_check(ctx, bpf_session_is_return());









	return uprobe_multi_check(ctx, bpf_session_is_return(ctx));









}