diff options
author | John Fastabend <john.fastabend@gmail.com> | 2018-04-25 15:08:53 -0700 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-04-26 22:23:02 +0200 |
commit | 815425567dea6c54494e85050631d6bdda907c5d (patch) | |
tree | b4b8abbdd15ea200595ae81616e94af48bd3e4ae | |
parent | 25eb0ea7174c6e84f21fa59dccbddd0318b17b12 (diff) |
bpf: fix uninitialized variable in bpf tools
Here the variable cont is used as the saved_pointer for a call to
strtok_r(). It is safe to use the value uninitialized in this
context however and the later reference is only ever used if
the strtok_r is successful. But, 'gcc-5' at least doesn't have all
this knowledge so initialize cont to NULL. Additionally, do the
natural NULL check before accessing just for completness.
The warning is the following:
./bpf/tools/bpf/bpf_dbg.c: In function ‘cmd_load’:
./bpf/tools/bpf/bpf_dbg.c:1077:13: warning: ‘cont’ may be used uninitialized in this function [-Wmaybe-uninitialized]
} else if (matches(subcmd, "pcap") == 0) {
Fixes: fd981e3c321a "filter: bpf_dbg: add minimal bpf debugger"
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
-rw-r--r-- | tools/bpf/bpf_dbg.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/tools/bpf/bpf_dbg.c b/tools/bpf/bpf_dbg.c index 4f254bcc4423..61b9aa5d6415 100644 --- a/tools/bpf/bpf_dbg.c +++ b/tools/bpf/bpf_dbg.c @@ -1063,7 +1063,7 @@ static int cmd_load_pcap(char *file) static int cmd_load(char *arg) { - char *subcmd, *cont, *tmp = strdup(arg); + char *subcmd, *cont = NULL, *tmp = strdup(arg); int ret = CMD_OK; subcmd = strtok_r(tmp, " ", &cont); @@ -1073,7 +1073,10 @@ static int cmd_load(char *arg) bpf_reset(); bpf_reset_breakpoints(); - ret = cmd_load_bpf(cont); + if (!cont) + ret = CMD_ERR; + else + ret = cmd_load_bpf(cont); } else if (matches(subcmd, "pcap") == 0) { ret = cmd_load_pcap(cont); } else { |