From e2043bd5578948d7a0cd1fe90fcdb6522a69c2c5 Mon Sep 17 00:00:00 2001
From: Jiri Olsa <jolsa@kernel.org>
Date: Mon, 4 Nov 2024 18:52:54 +0100
Subject: [PATCH] lib/buildid: Fix build ID parsing logic

The parse_build_id_buf does not account Elf32_Nhdr header size
when getting the build id data pointer and returns wrong build
id data as result.

This is problem only for stable trees that merged 84887f4c1c3a
fix, the upstream build id code was refactored and returns proper
build id.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Fixes: 84887f4c1c3a ("lib/buildid: harden build ID parsing logic")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 lib/buildid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/buildid.c b/lib/buildid.c
index e41fb0ee405f6..cc5da016b2351 100644
--- a/lib/buildid.c
+++ b/lib/buildid.c
@@ -40,7 +40,7 @@ static int parse_build_id_buf(unsigned char *build_id,
 		    name_sz == note_name_sz &&
 		    memcmp(nhdr + 1, note_name, note_name_sz) == 0 &&
 		    desc_sz > 0 && desc_sz <= BUILD_ID_SIZE_MAX) {
-			data = note_start + note_off + ALIGN(note_name_sz, 4);
+			data = note_start + note_off + sizeof(Elf32_Nhdr) + ALIGN(note_name_sz, 4);
 			memcpy(build_id, data, desc_sz);
 			memset(build_id + desc_sz, 0, BUILD_ID_SIZE_MAX - desc_sz);
 			if (size)
-- 
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