executor: add runner mode

Move all syz-fuzzer logic into syz-executor and remove syz-fuzzer.
Also restore syz-runtest functionality in the manager.

Update #4917 (sets most signal handlers to SIG_IGN)

1 files changed, 192 insertions, 0 deletions

diff --git a/executor/conn.h b/executor/conn.h
new file mode 100644
index 000000000..19026748d
--- /dev/null
+++ b/executor/conn.h
@@ -0,0 +1,192 @@
+// Copyright 2024 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+#include <arpa/inet.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <string.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+
+#include <vector>
+
+// Connection represents a client TCP connection.
+// It connects to the given addr:port and allows to send/receive
+// flatbuffers-encoded messages.
+class Connection
+{
+public:
+	Connection(const char* addr, const char* port)
+	    : fd_(Connect(addr, port))
+	{
+	}
+
+	int FD() const
+	{
+		return fd_;
+	}
+
+	template <typename Msg>
+	void Send(const Msg& msg)
+	{
+		typedef typename Msg::TableType Raw;
+		auto off = Raw::Pack(fbb_, &msg);
+		fbb_.FinishSizePrefixed(off);
+		auto data = fbb_.GetBufferSpan();
+		Send(data.data(), data.size());
+		fbb_.Reset();
+	}
+
+	template <typename Msg>
+	void Recv(Msg& msg)
+	{
+		typedef typename Msg::TableType Raw;
+		flatbuffers::uoffset_t size;
+		Recv(&size, sizeof(size));
+		recv_buf_.resize(size);
+		Recv(recv_buf_.data(), size);
+		auto raw = flatbuffers::GetRoot<Raw>(recv_buf_.data());
+		raw->UnPackTo(&msg);
+	}
+
+	void Send(const void* data, size_t size)
+	{
+		for (size_t sent = 0; sent < size;) {
+			ssize_t n = write(fd_, static_cast<const char*>(data) + sent, size - sent);
+			if (n > 0) {
+				sent += n;
+				continue;
+			}
+			if (errno == EINTR)
+				continue;
+			if (errno == EAGAIN) {
+				sleep_ms(1);
+				continue;
+			}
+			failmsg("failed to send rpc", "fd=%d want=%zu sent=%zu n=%zd", fd_, size, sent, n);
+		}
+	}
+
+private:
+	const int fd_;
+	std::vector<char> recv_buf_;
+	flatbuffers::FlatBufferBuilder fbb_;
+
+	void Recv(void* data, size_t size)
+	{
+		for (size_t recv = 0; recv < size;) {
+			ssize_t n = read(fd_, static_cast<char*>(data) + recv, size - recv);
+			if (n > 0) {
+				recv += n;
+				continue;
+			}
+			if (errno == EINTR)
+				continue;
+			if (errno == EAGAIN) {
+				sleep_ms(1);
+				continue;
+			}
+			failmsg("failed to recv rpc", "fd=%d want=%zu sent=%zu n=%zd", fd_, size, recv, n);
+		}
+	}
+
+	static int Connect(const char* addr, const char* ports)
+	{
+		int port = atoi(ports);
+		if (port == 0)
+			failmsg("failed to parse manager port", "port=%s", ports);
+		if (!strcmp(addr, "stdin"))
+			return STDIN_FILENO;
+		sockaddr_in saddr4 = {};
+		saddr4.sin_family = AF_INET;
+		saddr4.sin_port = htons(port);
+		if (inet_pton(AF_INET, addr, &saddr4.sin_addr))
+			return Connect(&saddr4, &saddr4.sin_addr, port);
+		sockaddr_in6 saddr6 = {};
+		saddr6.sin6_family = AF_INET6;
+		saddr6.sin6_port = htons(port);
+		if (inet_pton(AF_INET6, addr, &saddr6.sin6_addr))
+			return Connect(&saddr6, &saddr6.sin6_addr, port);
+		auto* hostent = gethostbyname(addr);
+		if (!hostent)
+			failmsg("failed to resolve manager addr", "addr=%s h_errno=%d", addr, h_errno);
+		for (char** addr = hostent->h_addr_list; *addr; addr++) {
+			int fd;
+			if (hostent->h_addrtype == AF_INET) {
+				memcpy(&saddr4.sin_addr, *addr, std::min<size_t>(hostent->h_length, sizeof(saddr4.sin_addr)));
+				fd = Connect(&saddr4, &saddr4.sin_addr, port);
+			} else if (hostent->h_addrtype == AF_INET6) {
+				memcpy(&saddr6.sin6_addr, *addr, std::min<size_t>(hostent->h_length, sizeof(saddr6.sin6_addr)));
+				fd = Connect(&saddr6, &saddr6.sin6_addr, port);
+			} else {
+				failmsg("unknown socket family", "family=%d", hostent->h_addrtype);
+			}
+			if (fd != -1)
+				return fd;
+		}
+		failmsg("can't connect to manager", "addr=%s:%s", addr, ports);
+	}
+
+	template <typename addr_t>
+	static int Connect(addr_t* addr, void* ip, int port)
+	{
+		auto* saddr = reinterpret_cast<sockaddr*>(addr);
+		int fd = socket(saddr->sa_family, SOCK_STREAM, IPPROTO_TCP);
+		if (fd == -1)
+			fail("failed to create socket");
+		char str[128] = {};
+		inet_ntop(saddr->sa_family, ip, str, sizeof(str));
+		if (connect(fd, saddr, sizeof(*addr))) {
+			printf("failed to connect to manager at %s:%d: %s\n", str, port, strerror(errno));
+			close(fd);
+			return -1;
+		}
+		return fd;
+	}
+
+	Connection(const Connection&) = delete;
+	Connection& operator=(const Connection&) = delete;
+};
+
+// Select is a wrapper around select system call.
+class Select
+{
+public:
+	Select()
+	{
+		FD_ZERO(&rdset_);
+	}
+
+	void Arm(int fd)
+	{
+		FD_SET(fd, &rdset_);
+		max_fd_ = std::max(max_fd_, fd);
+	}
+
+	bool Ready(int fd) const
+	{
+		return FD_ISSET(fd, &rdset_);
+	}
+
+	void Wait(int ms)
+	{
+		timespec timeout = {.tv_sec = ms / 1000, .tv_nsec = (ms % 1000) * 1000 * 1000};
+		if (pselect(max_fd_ + 1, &rdset_, nullptr, nullptr, &timeout, nullptr) < 0) {
+			if (errno != EINTR && errno != EAGAIN)
+				fail("pselect failed");
+		}
+	}
+
+	static void Prepare(int fd)
+	{
+		if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK))
+			fail("fcntl(O_NONBLOCK) failed");
+	}
+
+private:
+	fd_set rdset_;
+	int max_fd_ = -1;
+
+	Select(const Select&) = delete;
+	Select& operator=(const Select&) = delete;
+};