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Rozycki" Subject: [PATCH v4 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-Migadu-Flow: FLOW_IN X-Migadu-Country: SG X-Migadu-Spam-Score: -1.11 X-Migadu-Queue-Id: 702BAD7A60 X-Migadu-Scanner: mx10.migadu.com X-TUID: yG/nyHhor1Yn X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 0017A1C000A X-Stat-Signature: h63etynjkt3ywzg5k3d8ptos6ny9ueq8 X-Rspam-User: X-HE-Tag: 1762717728-796879 X-HE-Meta: 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 poapSy+U q8UnU/ymSoKLihSJTWZtsBaU3Bopd4DSYPm0873c/05qoqKSxWma9bGTXcrvffkJf0hjBEsEqfRZQ28CYSWOQWb6j0E1NitmG+NOp1G2CqP4YhO70JfIS5PrVv/j+Y32mHevBh6LxgKF05BOyCpcEcCl/oq0jHX7wNasu 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