On 02/12/2018 11:08 AM, Daniel P. Berrangé wrote: > The fix for CVE-2018-6764 introduced a potential deadlock scenario > that gets triggered by the NSS module when virGetHostname() calls > getaddrinfo to resolve the hostname: > > #0 0x00007f6e714b57e7 in futex_wait > #1 futex_wait_simple > #2 __pthread_once_slow > #3 0x00007f6e71d16e7d in virOnce > #4 0x00007f6e71d0997c in virLogInitialize > #5 0x00007f6e71d0a09a in virLogVMessage > #6 0x00007f6e71d09ffd in virLogMessage > #7 0x00007f6e71d0db22 in virObjectNew > #8 0x00007f6e71d0dbf1 in virObjectLockableNew > #9 0x00007f6e71d0d3e5 in virMacMapNew > #10 0x00007f6e71cdc50a in findLease > #11 0x00007f6e71cdcc56 in _nss_libvirt_gethostbyname4_r > #12 0x00007f6e724631fc in gaih_inet > #13 0x00007f6e72464697 in __GI_getaddrinfo > #14 0x00007f6e71d19e81 in virGetHostnameImpl > #15 0x00007f6e71d1a057 in virGetHostnameQuiet > #16 0x00007f6e71d09936 in virLogOnceInit > #17 0x00007f6e71d09952 in virLogOnce > #18 0x00007f6e714b5829 in __pthread_once_slow > #19 0x00007f6e71d16e7d in virOnce > #20 0x00007f6e71d0997c in virLogInitialize > #21 0x00007f6e71d0a09a in virLogVMessage > #22 0x00007f6e71d09ffd in virLogMessage > #23 0x00007f6e71d0db22 in virObjectNew > #24 0x00007f6e71d0dbf1 in virObjectLockableNew > #25 0x00007f6e71d0d3e5 in virMacMapNew > #26 0x00007f6e71cdc50a in findLease > #27 0x00007f6e71cdc839 in _nss_libvirt_gethostbyname3_r > #28 0x00007f6e71cdc724 in _nss_libvirt_gethostbyname2_r > #29 0x00007f6e7248f72f in __gethostbyname2_r > #30 0x00007f6e7248f494 in gethostbyname2 > #31 0x000056348c30c36d in hosts_keys > #32 0x000056348c30b7d2 in main > > Fortunately the extra stuff virGetHostname does is totally irrelevant to > the needs of the logging code, so we can just inline a call to the > native hostname() syscall directly. > > Signed-off-by: Daniel P. Berrangé <berrange@xxxxxxxxxx> > --- > src/util/virlog.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) ACK Michal -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
