Re: [libvirt PATCH v2] ch: Fix cloud-hypervisor version processing

On Tue, Sep 05, 2023 at 12:44:25PM -0500, Praveen K Paladugu wrote: > Refactor the version processing logic in ch driver to support versions > from non-release cloud-hypervisor binaries. This version also supports > versions with branch prefixes in them. > > Signed-off-by: Praveen K Paladugu <prapal(a)linux.microsoft.com&gt; > --- > src/ch/ch_conf.c | 39 ++++++++++++++++++++++++++++++++++++--- > 1 file changed, 36 insertions(+), 3 deletions(-) > > diff --git a/src/ch/ch_conf.c b/src/ch/ch_conf.c > index a8565d9537..a0849bfbd6 100644 > --- a/src/ch/ch_conf.c > +++ b/src/ch/ch_conf.c > @@ -172,6 +172,33 @@ virCHDriverConfigDispose(void *obj) > > #define MIN_VERSION ((15 * 1000000) + (0 * 1000) + (0)) > > +/** > + * chPreProcessVersionString - crop branch, commit info and return just the version > + */ > +static char * > +chPreProcessVersionString(char *version) > +{ > + g_autofree char *new_version = version; > + char *tmp_version; > + > + if ((tmp_version = strrchr(version, '/')) != NULL) { > + new_version = tmp_version + 1; > + } > + > + if (new_version[0] == 'v') { > + new_version = new_version + 1; > + } This is unsafe - 'new_version' is marked g_autofree, and this pointer manipulation will cause it to try to free a location /after/ the start of the allocation. Except you have no error paths, so the g_autofree will never trigger. Remove the g_autofree + g_steal_pointer as they're unsafe if the former ever ran.

> + // Duplicate the string in both cases. This would allow the calling method > + // free the returned string in a consistent manner. > + if ((tmp_version = strchr(new_version, '-')) != NULL) { > + new_version = g_strndup(new_version, tmp_version - new_version); > + } else{ > + new_version = g_strdup(new_version); > + } > + > + return g_steal_pointer(&new_version); > + > +} > int > chExtractVersion(virCHDriver *driver) > { > @@ -193,19 +220,25 @@ chExtractVersion(virCHDriver *driver) > > tmp = help; > > - /* expected format: cloud-hypervisor v<major>.<minor>.<micro> */ > - if ((tmp = STRSKIP(tmp, "cloud-hypervisor v")) == NULL) { > + /* Below are some example version formats and expected outputs: > + * cloud-hypervisor v32.0.0 (expected: 32.0.0) > + * cloud-hypervisor v33.0-104-ge0e3779e-dirty (expected: 33.0) > + * cloud-hypervisor testing/v32.0.131-1-ga5d6db5c-dirty (expected: 32.0.131) > + */ > + if ((tmp = STRSKIP(tmp, "cloud-hypervisor ")) == NULL) { > virReportError(VIR_ERR_INTERNAL_ERROR, "%s", > _("Unexpected output of cloud-hypervisor binary")); > return -1; > } > > + tmp = chPreProcessVersionString(tmp); > + VIR_DEBUG("Cloud-Hypervisor version detected: %s", tmp); > + > if (virStringParseVersion(&version, tmp, true) < 0) { > virReportError(VIR_ERR_INTERNAL_ERROR, > _("Unable to parse cloud-hypervisor version: %1$s"), tmp); > return -1; > } > - > if (version < MIN_VERSION) { > virReportError(VIR_ERR_INTERNAL_ERROR, "%s", > _("Cloud-Hypervisor version is too old (v15.0 is the minimum supported version)")); > -- > 2.41.0 > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|