SymbX/systemd
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

sd-daemon: Add vsock fallback to SOCK_STREAM

Browse Source 
SOCK_SEQPACKET is only supported on recent kernels. Let's add a
fallback to SOCK_STREAM if it is not supported.

To accomodate SOCK_STREAM, we also modify
pid_notify_with_fds_internal() to do sendmsg() in a loop as with
SOCK_STREAM, sendmsg() is not guaranteed to write all data in a single
syscall or fail otherwise.
This commit is contained in:
Daan De Meyer
2023-06-13 14:24:44 +02:00
parent 56d02f2969
commit 7f78d3431b
1 changed files with 28 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/libsystemd/sd-daemon/sd-daemon.c
+28 -12
View File
@@ -466,6 +466,7 @@ static int pid_notify_with_fds_internal(
struct cmsghdr *cmsg = NULL;
const char *e;
bool send_ucred;
ssize_t n;
int type, r;
if (!state)
@@ -502,6 +503,10 @@ static int pid_notify_with_fds_internal(
type = SOCK_SEQPACKET;
fd = socket(address.sockaddr.sa.sa_family, type|SOCK_CLOEXEC, 0);
if (fd < 0 && ERRNO_IS_NOT_SUPPORTED(errno)) {
type = SOCK_STREAM;
fd = socket(address.sockaddr.sa.sa_family, type|SOCK_CLOEXEC, 0);
}
if (fd < 0)
return log_debug_errno(errno, "Failed to open %s socket to '%s': %m", socket_address_type_to_string(type), e);
}
@@ -563,21 +568,32 @@ static int pid_notify_with_fds_internal(
}
}
/* First try with fake ucred data, as requested */
if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) >= 0)
return 1;
do {
/* First try with fake ucred data, as requested */
n = sendmsg(fd, &msghdr, MSG_NOSIGNAL);
if (n < 0) {
if (!send_ucred)
return log_debug_errno(errno, "Failed to send notify message to '%s': %m", e);
/* If that failed, try with our own ucred instead */
if (send_ucred) {
msghdr.msg_controllen -= CMSG_SPACE(sizeof(struct ucred));
if (msghdr.msg_controllen == 0)
/* If that failed, try with our own ucred instead */
msghdr.msg_controllen -= CMSG_SPACE(sizeof(struct ucred));
if (msghdr.msg_controllen == 0)
msghdr.msg_control = NULL;
n = 0;
send_ucred = false;
} else {
/* Unless we're using SOCK_STREAM, we expect to write all the contents immediately. */
if (type != SOCK_STREAM && (size_t) n < IOVEC_TOTAL_SIZE(msghdr.msg_iov, msghdr.msg_iovlen))
return -EIO;
/* Make sure we only send fds and ucred once, even if we're using SOCK_STREAM. */
msghdr.msg_control = NULL;
msghdr.msg_controllen = 0;
}
} while (!IOVEC_INCREMENT(msghdr.msg_iov, msghdr.msg_iovlen, n));
if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) >= 0)
return 1;
}
return log_debug_errno(errno, "Failed to send notify message to '%s': %m", e);
return 1;
}
_public_ int sd_pid_notify_with_fds(