Re: [PATCH] selftest:net: Fix uninit pointers and return values
From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: 2025-09-29 14:19:04
Also in:
linux-kselftest, lkml, llvm
[PATCH net] and a Fixes tag Sidharth Seela wrote:
Fix uninitialized character pointers, and functions that return
undefined values. These issues were caught by running clang using LLVM=1
option; and are as follows:
--
ovpn-cli.c:1587:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1587 | if (!sock) {
| ^~~~~
ovpn-cli.c:1635:9: note: uninitialized use occurs here
1635 | return ret;
| ^~~
ovpn-cli.c:1587:2: note: remove the 'if' if its condition is always false
1587 | if (!sock) {
| ^~~~~~~~~~~~
1588 | fprintf(stderr, "cannot allocate netlink socket\n");
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1589 | goto err_free;
| ~~~~~~~~~~~~~~
1590 | }
| ~
ovpn-cli.c:1584:15: note: initialize the variable 'ret' to silence this warning
1584 | int mcid, ret;
| ^
| = 0
ovpn-cli.c:2107:7: warning: variable 'ret' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
2107 | case CMD_INVALID:
| ^~~~~~~~~~~
ovpn-cli.c:2111:9: note: uninitialized use occurs here
2111 | return ret;
| ^~~
ovpn-cli.c:1939:12: note: initialize the variable 'ret' to silence this warning
1939 | int n, ret;
| ^These two look legitimate.
| -- txtimestamp.c:240:2: warning: variable 'tsname' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized] 240 | default:
Does not need a fix. The default statement calls error() which exits the program.
| ^~~~~~~
txtimestamp.c:244:20: note: uninitialized use occurs here
244 | __print_timestamp(tsname, &tss->ts[0], tskey, payload_len);
| ^~~~~~
txtimestamp.c:220:20: note: initialize the variable 'tsname' to silence this warning
220 | const char *tsname;
| ^
| = NULL
--
so_txtime.c:210:3: warning: variable 'reason' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
210 | default:
| ^~~~~~~Same.
so_txtime.c:219:27: note: uninitialized use occurs here
219 | data[ret - 1], tstamp, reason);
| ^~~~~~
so_txtime.c:177:21: note: initialize the variable 'reason' to silence this warning
177 | const char *reason;
| ^
|
--
Signed-off-by: Sidharth Seela <redacted>Agreed on all the occurrences and the ovpn fixes.
quoted hunk ↗ jump to hunk
---diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c index 9201f2905f2c..20d00378f34a 100644 --- a/tools/testing/selftests/net/ovpn/ovpn-cli.c +++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c@@ -1581,7 +1581,7 @@ static int ovpn_listen_mcast(void) { struct nl_sock *sock; struct nl_cb *cb; - int mcid, ret; + int mcid, ret = -1; sock = nl_socket_alloc(); if (!sock) {@@ -1936,7 +1936,7 @@ static int ovpn_run_cmd(struct ovpn_ctx *ovpn) { char peer_id[10], vpnip[INET6_ADDRSTRLEN], laddr[128], lport[10]; char raddr[128], rport[10]; - int n, ret; + int n, ret = -1; FILE *fp; switch (ovpn->cmd) {diff --git a/tools/testing/selftests/net/so_txtime.c b/tools/testing/selftests/net/so_txtime.c index 8457b7ccbc09..b76df1efc2ef 100644 --- a/tools/testing/selftests/net/so_txtime.c +++ b/tools/testing/selftests/net/so_txtime.c@@ -174,7 +174,7 @@ static int do_recv_errqueue_timeout(int fdt) msg.msg_controllen = sizeof(control); while (1) { - const char *reason; + const char *reason = NULL;
Since reason is a string that's printed, better to initialize it to a string. Preferably in the case statement, e.g., "unknown errno".
quoted hunk ↗ jump to hunk
ret = recvmsg(fdt, &msg, MSG_ERRQUEUE); if (ret == -1 && errno == EAGAIN)diff --git a/tools/testing/selftests/net/txtimestamp.c b/tools/testing/selftests/net/txtimestamp.c index dae91eb97d69..bcc14688661d 100644 --- a/tools/testing/selftests/net/txtimestamp.c +++ b/tools/testing/selftests/net/txtimestamp.c@@ -217,7 +217,7 @@ static void print_timestamp_usr(void) static void print_timestamp(struct scm_timestamping *tss, int tstype, int tskey, int payload_len) { - const char *tsname; + const char *tsname = NULL; validate_key(tskey, tstype);-- 2.47.3