[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20190712121629.148244689@linuxfoundation.org>
Date: Fri, 12 Jul 2019 14:17:55 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Chang-Hsien Tsai <luke.tw@...il.com>,
Daniel Borkmann <daniel@...earbox.net>,
Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.1 011/138] samples, bpf: fix to change the buffer size for read()
[ Upstream commit f7c2d64bac1be2ff32f8e4f500c6e5429c1003e0 ]
If the trace for read is larger than 4096, the return
value sz will be 4096. This results in off-by-one error
on buf:
static char buf[4096];
ssize_t sz;
sz = read(trace_fd, buf, sizeof(buf));
if (sz > 0) {
buf[sz] = 0;
puts(buf);
}
Signed-off-by: Chang-Hsien Tsai <luke.tw@...il.com>
Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
samples/bpf/bpf_load.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index eae7b635343d..6e87cc831e84 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -678,7 +678,7 @@ void read_trace_pipe(void)
static char buf[4096];
ssize_t sz;
- sz = read(trace_fd, buf, sizeof(buf));
+ sz = read(trace_fd, buf, sizeof(buf) - 1);
if (sz > 0) {
buf[sz] = 0;
puts(buf);
--
2.20.1
Powered by blists - more mailing lists