[PATCH 2/2] read-cache: check range before dereferencing an array element

["Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>]

From: Johannes Schindelin <johannes.schindelin@gmx.de>

Before accessing an array element at a given index, we should make sure
that the index is within the desired bounds, not afterwards, otherwise
it may not make sense to even access the array element in the first
place.

Pointed out by CodeQL's `cpp/offset-use-before-range-check` rule.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 read-cache.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/read-cache.c b/read-cache.c
index e678c13e8f1..08ae66ad609 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -2686,8 +2686,8 @@ static int ce_write_entry(struct hashfile *f, struct cache_entry *ce,
 		int common, to_remove, prefix_size;
 		unsigned char to_remove_vi[16];
 		for (common = 0;
-		     (ce->name[common] &&
-		      common < previous_name->len &&
+		     (common < previous_name->len &&
+		      ce->name[common] &&
 		      ce->name[common] == previous_name->buf[common]);
 		     common++)
 			; /* still matching */
-- 
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