Commit 116c8f47 authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
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bpf: Fix bounds for bpf_prog_get_file_line linfo loop 

We may overrun the bounds because linfo and jited_linfo are already
advanced to prog->aux->linfo_idx, hence we must only iterate the
remaining elements until we reach prog->aux->nr_linfo. Adjust the
nr_linfo calculation to fix this. Reported in [0].

  [0]: https://lore.kernel.org/bpf/f3527af3b0620ce36e299e97e7532d2555018de2.camel@gmail.com



Reported-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Fixes: 0e521efa ("bpf: Add function to extract program source info")
Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250705053035.3020320-2-memxor@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 6e5cae9d

kernel/bpf/core.c

+3 −1
Original line number Diff line number Diff line
@@ -3244,6 +3244,7 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char * 
	struct bpf_line_info *linfo;

	void **jited_linfo;

	struct btf *btf;

	int nr_linfo;



	btf = prog->aux->btf;

	linfo = prog->aux->linfo;
@@ -3258,8 +3259,9 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char * 


	insn_start = linfo[0].insn_off;

	insn_end = insn_start + len;

	nr_linfo = prog->aux->nr_linfo - prog->aux->linfo_idx;



	for (int i = 0; i < prog->aux->nr_linfo &&

	for (int i = 0; i < nr_linfo &&

	     linfo[i].insn_off >= insn_start && linfo[i].insn_off < insn_end; i++) {

		if (jited_linfo[i] >= (void *)ip)

			break;