| Message ID | 20170801154609.29895-1-casey.callendrello@coreos.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | stephen hemminger |
| Headers | show |
On Tue, 1 Aug 2017 17:46:09 +0200 Casey Callendrello <casey.callendrello@coreos.com> wrote: > When ip netns {add|delete} is first run, it bind-mounts /var/run/netns > on top of itself, then marks it as shared. However, if there are already > bind-mounts in the directory from other tools, these would not be > propagated. Fix this by recursively bind-mounting. > > Signed-off-by: Casey Callendrello <casey.callendrello@coreos.com> > --- > ip/ipnetns.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > Looks good, but I want a review by Eric to make sure this doesn't break other things.
Stephen Hemminger <stephen@networkplumber.org> writes: > On Tue, 1 Aug 2017 17:46:09 +0200 > Casey Callendrello <casey.callendrello@coreos.com> wrote: > >> When ip netns {add|delete} is first run, it bind-mounts /var/run/netns >> on top of itself, then marks it as shared. However, if there are already >> bind-mounts in the directory from other tools, these would not be >> propagated. Fix this by recursively bind-mounting. >> >> Signed-off-by: Casey Callendrello <casey.callendrello@coreos.com> >> --- >> ip/ipnetns.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> > > Looks good, but I want a review by Eric to make sure this doesn't > break other things. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> I don't see any possible problems with this. This will just keep all of the mounts showing up. It would be really nice if we could at some point detect that a parent directory is shared (which happens with a common init system) and skip the steps of the bind mount and making them shared as they are redundant. However while that might also solve this issue that is something for another day. Eric
diff --git a/ip/ipnetns.c b/ip/ipnetns.c index 198e9de8..9ee1fe6a 100644 --- a/ip/ipnetns.c +++ b/ip/ipnetns.c @@ -636,7 +636,7 @@ static int netns_add(int argc, char **argv) } /* Upgrade NETNS_RUN_DIR to a mount point */ - if (mount(NETNS_RUN_DIR, NETNS_RUN_DIR, "none", MS_BIND, NULL)) { + if (mount(NETNS_RUN_DIR, NETNS_RUN_DIR, "none", MS_BIND | MS_REC, NULL)) { fprintf(stderr, "mount --bind %s %s failed: %s\n", NETNS_RUN_DIR, NETNS_RUN_DIR, strerror(errno)); return -1;
When ip netns {add|delete} is first run, it bind-mounts /var/run/netns on top of itself, then marks it as shared. However, if there are already bind-mounts in the directory from other tools, these would not be propagated. Fix this by recursively bind-mounting. Signed-off-by: Casey Callendrello <casey.callendrello@coreos.com> --- ip/ipnetns.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)