Commit Graph

29 Commits

Author SHA1 Message Date
Eric Blake
858c2476d9 command: avoid deadlock on EPIPE situation
It is possible to deadlock libvirt by having a domain with XML
longer than PIPE_BUF, and by writing a hook script that closes
stdin early.  This is because libvirt was keeping a copy of the
child's stdin read fd open, which means the write fd in the
parent will never see EPIPE (remember, libvirt should always be
run with SIGPIPE ignored, so we should never get a SIGPIPE signal).
Since there is no error, libvirt blocks waiting for a write to
complete, even though the only reader is also libvirt.  The
solution is to ensure that only the child can act as a reader
before the parent does any writes; and then dealing with the
fallout of dealing with EPIPE.

Thankfully, this is not a security hole - since the only way to
trigger the deadlock is to install a custom hook script, anyone
that already has privileges to install a hook script already has
privileges to do any number of other equally disruptive things
to libvirt; it would only be a security hole if an unprivileged
user could install a hook script to DoS a privileged user.

* src/util/command.c (virCommandRun): Close parent's copy of child
read fd earlier.
(virCommandProcessIO): Don't let EPIPE be fatal; the child may
be done parsing input.
* tests/commandhelper.c (main): Set up a SIGPIPE situation.
* tests/commandtest.c (test20): Trigger it.
* tests/commanddata/test20.log: New file.
2012-06-04 13:06:07 -06:00
Stefan Berger
59b935f5ae More coverity findings addressed
More bug extermination in the category of:

Error: CHECKED_RETURN:

/libvirt/src/conf/network_conf.c:595:
check_return: Calling function "virAsprintf" without checking return value (as is done elsewhere 515 out of 543 times).

/libvirt/src/qemu/qemu_process.c:2780:
unchecked_value: No check of the return value of "virAsprintf(&msg, "was paused (%s)", virDomainPausedReasonTypeToString(reason))".

/libvirt/tests/commandtest.c:809:
check_return: Calling function "setsid" without checking return value (as is done elsewhere 4 out of 5 times).

/libvirt/tests/commandtest.c:830:
unchecked_value: No check of the return value of "virTestGetDebug()".

/libvirt/tests/commandtest.c:831:
check_return: Calling function "virTestGetVerbose" without checking return value (as is done elsewhere 41 out of 42 times).

/libvirt/tests/commandtest.c:833:
check_return: Calling function "virInitialize" without checking return value (as is done elsewhere 18 out of 21 times).


One note about the error in commandtest line 809: setsid() seems to fail when running the test -- could be removed ?
2012-04-27 17:25:35 -04:00
Martin Kletzander
9943276fd2 Cleanup for a return statement in source files
Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:

List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$'

Found files were modified with this command:
sed -i -e                                                                 \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Then checked for nonsense.

The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e                            \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'
2012-03-26 14:45:22 -06:00
Eric Blake
c9ace552eb command: allow merging stdout and stderr in string capture
Sometimes, its easier to run children with 2>&1 in shell notation,
and just deal with stdout and stderr interleaved.  This was already
possible for fd handling; extend it to also work when doing string
capture of a child process.

* docs/internals/command.html.in: Document this.
* src/util/command.c (virCommandSetErrorBuffer): Likewise.
(virCommandRun, virExecWithHook): Implement it.
* tests/commandtest.c (test14): Test it.
* daemon/remote.c (remoteDispatchAuthPolkit): Use new command
feature.
2012-02-03 10:02:34 -07:00
Eric Blake
b2e13f9c44 tests: fix reversed comparisons
Otherwise, a failed test gives misleading output.

* tests/commandtest.c (test13, test14, test16): Pass arguments in
correct order.
2012-01-27 16:35:14 -07:00
Eric Blake
74ff57506c tests: avoid test failure on rawhide gnutls
I hit a VERY weird testsuite failure on rawhide, which included
_binary_ output to stderr, followed by a hang waiting for me
to type something! (Here, using ^@ for NUL):

$ ./commandtest
TEST: commandtest
      WARNING: gnome-keyring:: couldn't send data: Bad file descriptor
.WARNING: gnome-keyring:: couldn't send data: Bad file descriptor
.WARNING: gnome-keyring:: couldn't send data: Bad file descriptor
WARNING: gnome-keyring:: couldn't send data: Bad file descriptor
.8^@^@^@8^@^@^@^A^@^@^@^Bay^A^@^@^@)PRIVATE-GNOME-KEYRING-PKCS11-PROTOCOL-V-1

I finally traced it to the fact that gnome-keyring, called via
gnutls_global_init which is turn called by virNetTLSInit, opens
an internal fd that it expects to communicate to via a
pthread_atfork handler (never mind that it violates POSIX by
using non-async-signal-safe functions in that handler:
https://bugzilla.redhat.com/show_bug.cgi?id=772320).

Our problem stems from the fact that we pulled the rug out from
under the library's expectations by closing an fd that it had
just opened.  While we aren't responsible for fixing the bugs
in that pthread_atfork handler, we can at least avoid the bugs
by not closing the fd in the first place.

* tests/commandtest.c (mymain): Avoid closing fds that were opened
by virInitialize.
2012-01-06 14:24:32 -07:00
Eric Blake
2b045d39df command: handle empty buffer argument correctly
virBufferContentAndReset (intentionally) returns NULL for a buffer
with no content, but it is feasible to invoke a command with an
explicit empty string.

* src/util/command.c (virCommandAddEnvBuffer): Reject empty string.
(virCommandAddArgBuffer): Allow explicit empty argument.
* tests/commandtest.c (test9): Test it.
* tests/commanddata/test9.log: Adjust.
2011-12-03 15:55:46 -07:00
Daniel P. Berrange
2d533a465a Fix command test wrt gnutls initialize & fix debugging
The VIR_TEST_DEBUG and VIR_TEST_VERBOSE env vars did not work
because we replaced 'environ' with 'newenv'. Simply calling
virTestGetDebug/Verbose() before replacing the 'environ' ensures
we have processed the env variables.

The gnutls initialization code opens /dev/urandom and keeps that
FD around for later use. We have code which kills off FDs 3-5
to avoid interfereing with our test case. Move the virInitialize
call before this point, so it kills off the gnutls /dev/urandom
FD which is irrelevant for testing purposes

* tests/commandtest.c: Fix test debugging & make it robust against
  opened FDs
2011-08-25 12:05:54 +01:00
Eric Blake
be427e8b0b build: fix recent build failures
With gcc 4.5.1:

util/virpidfile.c: In function 'virPidFileAcquirePath':
util/virpidfile.c:308:66: error: nested extern declaration of '_gl_verify_function2' [-Wnested-externs]

Then in tests/commandtest.c, the new virPidFile APIs need to be used.

* src/util/virpidfile.c (virPidFileAcquirePath): Move verify to
top level.
* tests/commandtest.c: Use new pid APIs.
2011-08-12 16:16:29 -06:00
Matthias Bolte
c0e5994aef freebsd: Avoid /bin/true in commandtest
Rely on PATH and use just true, because on FreeBSD it's /usr/bin/true.
2011-07-29 12:12:58 +02:00
Matthias Bolte
cffba7ea3e tests: Unify style of test skipping code
Prefer 'return EXIT_AM_SKIP' over 'exit(EXIT_AM_SKIP)'.

Prefer 'int main(void)' over 'int main(int argc, char **argv)'.

Fix mymain signature in commandtest and nodeinfotest.
2011-07-29 12:12:58 +02:00
Laine Stump
d6354c1696 util: change virFile*Pid functions to return < 0 on failure
Although most functions in libvirt return 0 on success and < 0 on
failure, there are a few functions lingering around that return errno
(a positive value) on failure, and sometimes code calling those
functions incorrectly assumes the <0 standard. I noticed one of these
the other day when auditing networkStartDhcpDaemon after Guido Gunther
found a place where success was improperly returned on failure (that
patch has been acked and is pending a push). The problem was that it
expected the return value from virFileReadPid to be < 0 on failure,
but it was actually positive (it was also neglected to set the return
code in this case, similar to the bug found by Guido).

This all led to the fact that *all* of the virFile*Pid functions in
util.c are returning errno on failure. This patch remedies that
problem by changing them all to return -errno on failure, and makes
any necessary changes to callers of the functions. (In the meantime, I
also properly set the return code on failure of virFileReadPid in
networkStartDhcpDaemon).
2011-07-25 16:56:26 -04:00
Eric Blake
8e22e08935 build: rename files.h to virfile.h
In preparation for a future patch adding new virFile APIs.

* src/util/files.h, src/util/files.c: Move...
* src/util/virfile.h, src/util/virfile.c: ...here, and rename
functions to virFile prefix.  Macro names are intentionally
left alone.
* *.c: All '#include "files.h"' uses changed.
* src/Makefile.am (UTIL_SOURCES): Reflect rename.
* cfg.mk (exclude_file_name_regexp--sc_prohibit_close): Likewise.
* src/libvirt_private.syms: Likewise.
* docs/hacking.html.in: Likewise.
* HACKING: Regenerate.
2011-07-21 10:34:51 -06:00
Eric Blake
70ea7decbe tests: avoid crash when run under gcov
Running ./autobuild.sh failed when gcov is installed, because
commandtest ended up crashing during gcov's getenv() call after
exit() had already started.  I traced this nasty bug back to
a scoping issue present since the test introduction.

* tests/commandtest.c (mymain): Move newenv...
(newenv): ...to a scope that is still useful during exit().
2011-05-11 09:58:35 -06:00
Eric Blake
4b4e8b57c2 tests: avoid null pointer dereference
Unlikely to hit in real life, but clang noticed it.

* tests/commandtest.c (checkoutput, test4, test18): Avoid
unlink(NULL) on OOM.
2011-05-03 10:50:56 -06:00
Eric Blake
e39c46a5fd build: fix getcwd portability problems
* bootstrap.conf (gnulib_modules): Add getcwd-lgpl.
* tests/commandtest.c (checkoutput): Drop unused cwd.
* tests/commandhelper.c (main): Let getcwd malloc.
* tests/testutils.c (virTestMain): Likewise.
* tools/virsh.c (cmdPwd): Likewise.
(virshCmds): Expose cmdPwd and cmdCd on mingw.
2011-04-29 12:08:26 -06:00
Eric Blake
20986e58aa tests: simplify common setup
A few of the tests were missing basic sanity checks, while most
of them were doing copy-and-paste initialization (in fact, some
of them pasted the argc > 1 check more than once!).  It's much
nicer to do things in one common place, and minimizes the size of
the next patch that fixes getcwd usage.

* tests/testutils.h (EXIT_AM_HARDFAIL): New define.
(progname, abs_srcdir): Define for all tests.
(VIRT_TEST_MAIN): Change callback signature.
* tests/testutils.c (virtTestMain): Do more common init.
* tests/commandtest.c (mymain): Simplify.
* tests/cputest.c (mymain): Likewise.
* tests/esxutilstest.c (mymain): Likewise.
* tests/eventtest.c (mymain): Likewise.
* tests/hashtest.c (mymain): Likewise.
* tests/networkxml2xmltest.c (mymain): Likewise.
* tests/nodedevxml2xmltest.c (myname): Likewise.
* tests/nodeinfotest.c (mymain): Likewise.
* tests/nwfilterxml2xmltest.c (mymain): Likewise.
* tests/qemuargv2xmltest.c (mymain): Likewise.
* tests/qemuhelptest.c (mymain): Likewise.
* tests/qemuxml2argvtest.c (mymain): Likewise.
* tests/qemuxml2xmltest.c (mymain): Likewise.
* tests/qparamtest.c (mymain): Likewise.
* tests/sexpr2xmltest.c (mymain): Likewise.
* tests/sockettest.c (mymain): Likewise.
* tests/statstest.c (mymain): Likewise.
* tests/storagepoolxml2xmltest.c (mymain): Likewise.
* tests/storagevolxml2xmltest.c (mymain): Likewise.
* tests/virbuftest.c (mymain): Likewise.
* tests/virshtest.c (mymain): Likewise.
* tests/vmx2xmltest.c (mymain): Likewise.
* tests/xencapstest.c (mymain): Likewise.
* tests/xmconfigtest.c (mymain): Likewise.
* tests/xml2sexprtest.c (mymain): Likewise.
* tests/xml2vmxtest.c (mymain): Likewise.
2011-04-29 10:21:20 -06:00
Eric Blake
9ed545185f command: add virCommandAbort for cleanup paths
Sometimes, an asynchronous helper is started (such as a compressor
or iohelper program), but a later error means that we want to
abort that child.  Make this easier.

Note that since daemons and virCommandRunAsync can't mix, the only
time virCommandFree can reap a process is if someone did
virCommandRunAsync for a non-daemon and didn't stash the pid.

* src/util/command.h (virCommandAbort): New prototype.
* src/util/command.c (_virCommand): Add new field.
(virCommandRunAsync, virCommandWait): Track whether pid was used.
(virCommandFree): Reap child if caller did not request pid.
(virCommandAbort): New function.
* src/libvirt_private.syms (command.h): Export it.
* tests/commandtest.c (test19): New test.
2011-03-25 05:34:48 -06:00
Daniel P. Berrange
f0e9dfeca9 Make commandtest more robust wrt its execution environment
When executed from cron, commandtest would fail to correctly
identify daemon processes. Set session ID and process group
IDs at startup to ensure we have a consistent environment to
run in.

* tests/commandtest.c: Call setsid() and setpgid()
2011-02-25 11:02:08 +00:00
Eric Blake
e67ae61991 build: avoid close, system
* src/fdstream.c (virFDStreamOpenFile, virFDStreamCreateFile):
Use VIR_FORCE_CLOSE instead of close.
* tests/commandtest.c (mymain): Likewise.
* tools/virsh.c (editFile): Use virCommand instead of system.
* src/util/util.c (__virExec): Special case preservation of std
file descriptors to child.
2011-01-29 10:36:45 -07:00
Eric Blake
c7f28dec60 command: avoid hanging on daemon processes
* src/util/command.c (virCommandRun): Don't capture output on
daemons.
* tests/commandtest.c (test18): Expose the bug.
Reported by Laine Stump.
2010-12-21 11:49:49 -07:00
Eric Blake
7aaf4e6439 test: fix commandtest under autobuild.sh
* tests/commandtest.c (mymain): Kill off any leaked-in fds.
* autobuild.sh: Don't leak fds.

Signed-off-by: Eric Blake <eblake@redhat.com>
2010-12-13 16:04:56 -07:00
Eric Blake
2a5ccbefb0 build: distribute commandtest files
* tests/Makefile.am (SUBDIRS): Add commanddata.
* tests/commandtest.c (checkoutput): Delete correct file.
(test4): Delete pid file.
(mymain): Delete unused variable.
* tests/commanddata/Makefile.am: New file.
* configure.ac (AC_OUTPUT): Build new makefile.
Reported by Dominik Klein.
2010-12-10 08:44:53 -07:00
Eric Blake
cc5e2a849c command: improve behavior on no output
Guarantee that outbuf/errbuf are allocated on success, even if to the
empty string.  Caller always has to free the result, and empty output
check requires checking if *outbuf=='\0'.  Makes the API easier to use
safely.  Failure is best effort allocation (some paths, like
out-of-memory, cannot allocate a buffer, but most do), so caller must
free buffer on failure.

* docs/internals/command.html.in: Update documentation.
* src/util/command.c (virCommandSetOutputBuffer)
(virCommandSetErrorBuffer, virCommandProcessIO) Guarantee empty
string on no output.
* tests/commandtest.c (test17): New test.
2010-12-07 15:35:30 -07:00
Jiri Denemark
ea8389dd3d tests: Fix commandtest in VPATH build 2010-12-07 09:34:09 -07:00
Eric Blake
3c63a15b77 tests: fix leaks in commandtest
Most leaks could only occur on error cleanup paths.
2010-12-07 09:34:09 -07:00
Jiri Denemark
c1c1ff7e47 tests: Fix detection of expected error 2010-12-07 17:11:25 +01:00
Jiri Denemark
49c612b39e tests: Fix code formating in commandtest 2010-12-07 17:11:24 +01:00
Daniel P. Berrange
f16ad06fb2 Introduce new APIs for spawning processes
This introduces a new set of APIs in src/util/command.h
to use for invoking commands. This is intended to replace
all current usage of virRun and virExec variants, with a
more flexible and less error prone API.

* src/util/command.c: New file.
* src/util/command.h: New header.
* src/Makefile.am (UTIL_SOURCES): Build it.
* src/libvirt_private.syms: Export symbols internally.
* tests/commandtest.c: New test.
* tests/Makefile.am (check_PROGRAMS): Run it.
* tests/commandhelper.c: Auxiliary program.
* tests/commanddata/test2.log - test15.log: New expected outputs.
* cfg.mk (useless_free_options): Add virCommandFree.
(msg_gen_function): Add virCommandError.
* po/POTFILES.in: New translation.
* .x-sc_avoid_write: Add exemption.
* tests/.gitignore: Ignore new built file.
2010-12-02 16:00:44 -07:00