send-pack: fix leaking push cert nonce
When retrieving the push cert nonce from the server, we first store the constant returned by `server_feature_value()` and then, if the nonce is valid, we duplicate the nonce memory to a NUL-terminated string, so that we can pass it to `generate_push_cert()`. We never free the latter and thus cause a memory leak. Fix this by storing the limited-lifetime nonce into a scope-local variable such that the long-lived, allocated nonce can be easily freed without having to cast away its constness. This leak was exposed by t5534, but fixing it is not sufficient to make the whole test suite leak free. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
Sep 5, 2024 at 12:09 UTC
49d47eb5416d22f185877a57380a1ffc28f172e1
1 file changed
+7
-5
send-pack.c
+7
-5
@@ -501,7 +501,7 @@ int send_pack(struct send_pack_args *args,
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unsigned cmds_sent = 0;
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int ret;
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struct async demux;
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- const char *push_cert_nonce = NULL;
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+ char *push_cert_nonce = NULL;
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struct packet_reader reader;
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int use_bitmaps;
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@@ -550,10 +550,11 @@ int send_pack(struct send_pack_args *args,
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if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
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size_t len;
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- push_cert_nonce = server_feature_value("push-cert", &len);
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- if (push_cert_nonce) {
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- reject_invalid_nonce(push_cert_nonce, len);
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- push_cert_nonce = xmemdupz(push_cert_nonce, len);
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+ const char *nonce = server_feature_value("push-cert", &len);
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+
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+ if (nonce) {
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+ reject_invalid_nonce(nonce, len);
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+ push_cert_nonce = xmemdupz(nonce, len);
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} else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
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die(_("the receiving end does not support --signed push"));
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} else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
@@ -771,5 +772,6 @@ out:
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oid_array_clear(&commons);
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strbuf_release(&req_buf);
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strbuf_release(&cap_buf);
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+ free(push_cert_nonce);
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return ret;
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}