From: Taylor Blau <me@ttaylorr.com>
Date: Wed, 12 Jul 2023 23:38:08 +0000 (-0400)
Subject: commit-graph.c: prevent overflow in `load_tree_for_commit()`
X-Git-Tag: v2.42.0-rc0~39^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=51c31a6408c1eae3ad6c2f78ec136c1b415cad72;p=thirdparty%2Fgit.git

commit-graph.c: prevent overflow in `load_tree_for_commit()`

In a similar spirit as previous commits, ensure that we don't overflow
when computing an offset into the commit_data chunk when the (relative)
graph position exceeds 2^32-1/GRAPH_DATA_WIDTH.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/commit-graph.c b/commit-graph.c
index 5e32063d3d..08d773567f 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -980,7 +980,7 @@ static struct tree *load_tree_for_commit(struct repository *r,
 		g = g->base_graph;
 
 	commit_data = g->chunk_commit_data +
-			GRAPH_DATA_WIDTH * (graph_pos - g->num_commits_in_base);
+			st_mult(GRAPH_DATA_WIDTH, graph_pos - g->num_commits_in_base);
 
 	oidread(&oid, commit_data);
 	set_commit_tree(c, lookup_tree(r, &oid));