Re: [libvirt] [PATCH] LXC: make sure netns been enabled when trying to enable userns

-----Original Message----- From: Martin Kletzander [mailto:mkletzan@redhat.com] Sent: Friday, March 20, 2015 6:31 PM To: Chen, Hanxiao/陈 晗霄 Cc: libvir-list(a)redhat.com Subject: Re: [libvirt] [PATCH] LXC: make sure netns been enabled when trying to enable userns On Fri, Mar 20, 2015 at 05:58:22AM -0400, Chen Hanxiao wrote: >This patch revert commit: >7dc5dbc879bd0779924b5132a48b731a0bc04a1e > I haven't found this commit in the log, also this is not how reverts should be done, please use "git revert <commit_id>", it basically cherry-picks inverted version of that patch, so resolutions may be done for conflicts, and it will let you amend the commit messsage.

>Discussed at: >http://www.redhat.com/archives/libvir-list/2015-March/msg01023.html > >Signed-off-by: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com&gt; >--- > src/lxc/lxc_container.c | 45 ++++++++++++++++----------------------------- > 1 file changed, 16 insertions(+), 29 deletions(-) > >diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c >index cc20b6d..69a8f2f 100644 >--- a/src/lxc/lxc_container.c >+++ b/src/lxc/lxc_container.c >@@ -934,8 +934,6 @@ static int lxcContainerMountBasicFS(bool userns_enabled, > { > size_t i; > int rc = -1; >- char* mnt_src = NULL; >- int mnt_mflags; > > VIR_DEBUG("Mounting basic filesystems"); > >@@ -944,22 +942,17 @@ static int lxcContainerMountBasicFS(bool userns_enabled, > virLXCBasicMountInfo const *mnt = &lxcBasicMounts[i]; > > /* When enable userns but disable netns, kernel will >- * forbid us doing a new fresh mount for sysfs. >- * So we had to do a bind mount for sysfs instead. >+ * forbid us doing a new fresh mount for sysfs for security reason. >+ * So we should not allow this. > */ >- if (userns_enabled && netns_disabled && >- STREQ(mnt->src, "sysfs")) { >- if (VIR_STRDUP(mnt_src, "/sys") < 0) >- goto cleanup; >- mnt_mflags = MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY|MS_BIND; >- } else { >- if (VIR_STRDUP(mnt_src, mnt->src) < 0) >- goto cleanup; >- mnt_mflags = mnt->mflags; >+ if (userns_enabled && netns_disabled) { >+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", >+ _("Userns could not be enabled without netns")); >+ goto cleanup; > } > > VIR_DEBUG("Processing %s -> %s", >- mnt_src, mnt->dst); >+ mnt->src, mnt->dst); > > if (mnt->skipUnmounted) { > char *hostdir; >@@ -976,28 +969,24 @@ static int lxcContainerMountBasicFS(bool userns_enabled, > if (ret == 0) { > VIR_DEBUG("Skipping '%s' which isn't mounted in host", > mnt->dst); >- VIR_FREE(mnt_src); > continue; > } > } > > if (mnt->skipUserNS && userns_enabled) { > VIR_DEBUG("Skipping due to user ns enablement"); >- VIR_FREE(mnt_src); > continue; > } > > /* Skip mounts with missing source without shouting: it may be a > * missing folder in /proc due to the absence of a kernel feature */ >- if (STRPREFIX(mnt_src, "/") && !virFileExists(mnt_src)) { >- VIR_DEBUG("Skipping due to missing source: %s", mnt_src); >- VIR_FREE(mnt_src); >+ if (STRPREFIX(mnt->src, "/") && !virFileExists(mnt->src)) { >+ VIR_DEBUG("Skipping due to missing source: %s", mnt->src); > continue; > } > > if (mnt->skipNoNetns && netns_disabled) { > VIR_DEBUG("Skipping due to absence of network namespace"); >- VIR_FREE(mnt_src); > continue; > } > >@@ -1015,35 +1004,33 @@ static int lxcContainerMountBasicFS(bool userns_enabled, > * we mount the filesystem in read-write mode initially, and then do a > * separate read-only bind mount on top of that. > */ >- bindOverReadonly = !!(mnt_mflags & MS_RDONLY); >+ bindOverReadonly = !!(mnt->mflags & MS_RDONLY); > > VIR_DEBUG("Mount %s on %s type=%s flags=%x", >- mnt_src, mnt->dst, mnt->type, mnt_mflags & ~MS_RDONLY); >- if (mount(mnt_src, mnt->dst, mnt->type, mnt_mflags & ~MS_RDONLY, NULL) < 0) { >+ mnt->src, mnt->dst, mnt->type, mnt->mflags & ~MS_RDONLY); >+ if (mount(mnt->src, mnt->dst, mnt->type, mnt->mflags & ~MS_RDONLY, NULL) < 0) { > virReportSystemError(errno, > _("Failed to mount %s on %s type %s flags=%x"), >- mnt_src, mnt->dst, NULLSTR(mnt->type), >- mnt_mflags & ~MS_RDONLY); >+ mnt->src, mnt->dst, NULLSTR(mnt->type), >+ mnt->mflags & ~MS_RDONLY); > goto cleanup; > } > > if (bindOverReadonly && >- mount(mnt_src, mnt->dst, NULL, >+ mount(mnt->src, mnt->dst, NULL, > MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) { > virReportSystemError(errno, > _("Failed to re-mount %s on %s flags=%x"), >- mnt_src, mnt->dst, >+ mnt->src, mnt->dst, > MS_BIND|MS_REMOUNT|MS_RDONLY); > goto cleanup; > } > >- VIR_FREE(mnt_src); > } > > rc = 0; > > cleanup: >- VIR_FREE(mnt_src); > VIR_DEBUG("rc=%d", rc); > return rc; > } >-- >2.1.0 > >-- >libvir-list mailing list &gt;libvir-list(a)redhat.com >https://www.redhat.com/mailman/listinfo/libvir-list