Consider having a nc binary in the path with a space in its name, for example '/tmp/fo o/nc' This results in libvirt running SSH with the following arg value "'if ''/tmp/fo o/nc'' -q 2>&1 | grep \"requires an argument\" >/dev/null 2>&1; then ARG=-q0; else ARG=;fi;''/tmp/fo o/nc'' $ARG -U /var/run/libvirt/libvirt-sock'" The use of the single quote escaping was introduced by commit 6ac6238de33fc74e7545b245ae273d1bfd658808 Author: Guido Günther <agx(a)sigxcpu.org&gt; Date: Thu Oct 13 21:49:01 2011 +0200 Use virBufferEscapeShell in virNetSocketNewConnectSSH to escape the netcat command since it's passed to the shell. Adjust expected test case output accordingly. While the intention of this change was good, the result is broken as it is still underquoted. On the SSH server side, SSH itself runs the command via the shell. Our command is then invoking the shell again. Thus we see $ virsh -c qemu+ssh://root@domokun/system?netcat=%2Ftmp%2Ffo%20o%2Fnc list error: failed to connect to the hypervisor error: End of file while reading data: sh: /tmp/fo: No such file or directory: Input/output error With the second level of escaping added we can now successfully use a nc binary with a space in the path. The original test case added was misleading as it illustrated using a binary path of 'nc -4' which is not a path, it is a command with a separate argument, which is getting interpreted as a path. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; --- src/rpc/virnetclient.c | 8 ++++++++ src/rpc/virnetsocket.c | 9 +++++++++ tests/virnetsockettest.c | 6 +++--- 3 files changed, 20 insertions(+), 3 deletions(-) diff --git a/src/rpc/virnetclient.c b/src/rpc/virnetclient.c index 64855fb8d6..53d8b219ea 100644 --- a/src/rpc/virnetclient.c +++ b/src/rpc/virnetclient.c @@ -490,6 +490,10 @@ virNetClientPtr virNetClientNewLibSSH2(const char *host, DEFAULT_VALUE(knownHostsVerify, "normal"); virBufferEscapeShell(&buf, netcatPath); + if (!(nc = virBufferContentAndReset(&buf))) + goto no_memory; + virBufferEscapeShell(&buf, nc); + VIR_FREE(nc); if (!(nc = virBufferContentAndReset(&buf))) goto no_memory; @@ -596,6 +600,10 @@ virNetClientPtr virNetClientNewLibssh(const char *host, DEFAULT_VALUE(knownHostsVerify, "normal"); virBufferEscapeShell(&buf, netcatPath); + if (!(nc = virBufferContentAndReset(&buf))) + goto no_memory; + virBufferEscapeShell(&buf, nc); + VIR_FREE(nc); if (!(nc = virBufferContentAndReset(&buf))) goto no_memory; diff --git a/src/rpc/virnetsocket.c b/src/rpc/virnetsocket.c index ebd304707a..a469907779 100644 --- a/src/rpc/virnetsocket.c +++ b/src/rpc/virnetsocket.c @@ -903,6 +903,15 @@ int virNetSocketNewConnectSSH(const char *nodename, return -1; } quoted = virBufferContentAndReset(&buf); + + virBufferEscapeShell(&buf, quoted); + VIR_FREE(quoted); + if (virBufferCheckError(&buf) < 0) { + virCommandFree(cmd); + return -1; + } + quoted = virBufferContentAndReset(&buf); + /* * This ugly thing is a shell script to detect availability of * the -q option for 'nc': debian and suse based distros need this diff --git a/tests/virnetsockettest.c b/tests/virnetsockettest.c index bb8357f7cd..8cad351605 100644 --- a/tests/virnetsockettest.c +++ b/tests/virnetsockettest.c @@ -661,15 +661,15 @@ mymain(void) struct testSSHData sshData7 = { .nodename = "somehost", - .netcat = "nc -4", + .netcat = "/tmp/fo o/nc", .path = "/tmp/socket", .expectOut = "-T -e none -- somehost sh -c '" - "if ''nc -4'' -q 2>&1 | grep \"requires an argument\" >/dev/null 2>&1; then " + "if \'''\\''/tmp/fo o/nc'\\'''' -q 2>&1 | grep \"requires an argument\" >/dev/null 2>&1; then " "ARG=-q0;" "else " "ARG=;" "fi;" - "''nc -4'' $ARG -U /tmp/socket'\n", + "'''\\''/tmp/fo o/nc'\\'''' $ARG -U /tmp/socket'\n", }; if (virTestRun("SSH test 7", testSocketSSH, &sshData7) < 0) ret = -1; -- 2.21.0