diff options
| author | Chang-Hsien Tsai <luke.tw@gmail.com> | 2019-05-19 11:05:44 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2019-05-21 16:36:48 +0200 |
| commit | f7c2d64bac1be2ff32f8e4f500c6e5429c1003e0 (patch) | |
| tree | 9daa3a8015f051b4fc36020d310b266f652627e5 /samples/bpf | |
| parent | bpf: Check sk_fullsock() before returning from bpf_sk_lookup() (diff) | |
| download | linux-f7c2d64bac1be2ff32f8e4f500c6e5429c1003e0.tar.xz linux-f7c2d64bac1be2ff32f8e4f500c6e5429c1003e0.zip | |
samples, bpf: fix to change the buffer size for read()
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@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'samples/bpf')
| -rw-r--r-- | samples/bpf/bpf_load.c | 2 |
1 files changed, 1 insertions, 1 deletions
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); |