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Rozycki" Subject: [PATCH v5 3/4] kernel: Fix off-by-one benign bugs Message-ID: X-Mailer: git-send-email 2.51.0 References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 90EEF2000A X-Stat-Signature: 418hfjw38qf3uar3tdjb1jco8dn3wo9j X-Rspam-User: X-HE-Tag: 1765406809-964917 X-HE-Meta: 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 WjaS9ONe 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: We were wasting a byte due to an off-by-one bug. s[c]nprintf() doesn't write more than $2 bytes including the null byte, so trying to pass 'size-1' there is wasting one byte. This is essentially the same as the previous commit, in a different file. Cc: Marco Elver Cc: Kees Cook Cc: Christopher Bazley Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Alexander Potapenko Cc: Jann Horn Cc: Andrew Morton Cc: Linus Torvalds Cc: Rasmus Villemoes Cc: Marco Elver Cc: Michal Hocko Cc: Al Viro Signed-off-by: Alejandro Colomar --- kernel/kcsan/kcsan_test.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/kcsan/kcsan_test.c b/kernel/kcsan/kcsan_test.c index 219d22857c98..8ef8167be745 100644 --- a/kernel/kcsan/kcsan_test.c +++ b/kernel/kcsan/kcsan_test.c @@ -176,7 +176,7 @@ static bool __report_matches(const struct expect_report *r) /* Title */ cur = expect[0]; - end = &expect[0][sizeof(expect[0]) - 1]; + end = ARRAY_END(expect[0]); cur += scnprintf(cur, end - cur, "BUG: KCSAN: %s in ", is_assert ? "assert: race" : "data-race"); if (r->access[1].fn) { @@ -200,7 +200,7 @@ static bool __report_matches(const struct expect_report *r) /* Access 1 */ cur = expect[1]; - end = &expect[1][sizeof(expect[1]) - 1]; + end = ARRAY_END(expect[1]); if (!r->access[1].fn) cur += scnprintf(cur, end - cur, "race at unknown origin, with "); -- 2.51.0