From: Colin King <colin.king@canonical.com>
To: "Paul E . McKenney" <paulmck@kernel.org>,
Josh Triplett <josh@joshtriplett.org>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Joel Fernandes <joel@joelfernandes.org>,
rcu@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH][next] refperf: avoid null pointer dereference when buf fails to allocate
Date: Thu, 16 Jul 2020 15:38:56 +0100 [thread overview]
Message-ID: <20200716143856.1708123-1-colin.king@canonical.com> (raw)
From: Colin Ian King <colin.king@canonical.com>
Currently in the unlikely event that buf fails to be allocated it
is dereferenced a few times. Use the errexit flag to determine if
buf should be written to to avoid the null pointer dereferences.
Addresses-Coverity: ("Dereference after null check")
Fixes: f518f154ecef ("refperf: Dynamically allocate experiment-summary output buffer")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
kernel/rcu/refscale.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c
index d9291f883b54..952595c678b3 100644
--- a/kernel/rcu/refscale.c
+++ b/kernel/rcu/refscale.c
@@ -546,9 +546,11 @@ static int main_func(void *arg)
// Print the average of all experiments
SCALEOUT("END OF TEST. Calculating average duration per loop (nanoseconds)...\n");
- buf[0] = 0;
- strcat(buf, "\n");
- strcat(buf, "Runs\tTime(ns)\n");
+ if (!errexit) {
+ buf[0] = 0;
+ strcat(buf, "\n");
+ strcat(buf, "Runs\tTime(ns)\n");
+ }
for (exp = 0; exp < nruns; exp++) {
u64 avg;
--
2.27.0
next reply other threads:[~2020-07-16 14:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-16 14:38 Colin King [this message]
2020-07-20 16:26 ` [PATCH][next] refperf: avoid null pointer dereference when buf fails to allocate Paul E. McKenney
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