linux-kernel - [PATCH 5.15 257/667] libbpf: Fix logic for finding matching program for CO-RE relocation

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue,  7 Jun 2022 18:58:42 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Andrii Nakryiko <andrii@...nel.org>,
        Alexei Starovoitov <ast@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.15 257/667] libbpf: Fix logic for finding matching program for CO-RE relocation

From: Andrii Nakryiko <andrii@...nel.org>

[ Upstream commit 966a7509325395c51c5f6d89e7352b0585e4804b ]

Fix the bug in bpf_object__relocate_core() which can lead to finding
invalid matching BPF program when processing CO-RE relocation. IF
matching program is not found, last encountered program will be assumed
to be correct program and thus error detection won't detect the problem.

Fixes: 9c82a63cf370 ("libbpf: Fix CO-RE relocs against .text section")
Signed-off-by: Andrii Nakryiko <andrii@...nel.org>
Signed-off-by: Alexei Starovoitov <ast@...nel.org>
Link: https://lore.kernel.org/bpf/20220426004511.2691730-4-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 tools/lib/bpf/libbpf.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 5612d0938fc9..1ba2dd3523f8 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -5221,9 +5221,10 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path)
 		 */
 		prog = NULL;
 		for (i = 0; i < obj->nr_programs; i++) {
-			prog = &obj->programs[i];
-			if (strcmp(prog->sec_name, sec_name) == 0)
+			if (strcmp(obj->programs[i].sec_name, sec_name) == 0) {
+				prog = &obj->programs[i];
 				break;
+			}
 		}
 		if (!prog) {
 			pr_warn("sec '%s': failed to find a BPF program\n", sec_name);
-- 
2.35.1