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Rozycki" Subject: [PATCH v6 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-Queue-Id: 6028140009 X-Stat-Signature: 3racxj3skjt63wistdzqmga6nz3j1gk8 X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1765449845-215653 X-HE-Meta: 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 M0EkHBc+ 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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