Bug 31232
| Summary: | /proc/sys/net/ipv6 has two neigh folders | ||
|---|---|---|---|
| Product: | Networking | Reporter: | Andreas Sundstrom (sunkan) |
| Component: | IPV6 | Assignee: | Hideaki YOSHIFUJI (yoshfuji) |
| Status: | CLOSED CODE_FIX | ||
| Severity: | low | CC: | alan, florian |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 2.6.38 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
|
Description
Andreas Sundstrom
2011-03-16 22:06:28 UTC
(switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Wed, 16 Mar 2011 22:06:34 GMT bugzilla-daemon@bugzilla.kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=31232 > > Summary: /proc/sys/net/ipv6 has two neigh folders > Product: Networking > Version: 2.5 > Kernel Version: 2.6.38 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: low > Priority: P1 > Component: IPV6 > AssignedTo: yoshfuji@linux-ipv6.org > ReportedBy: sunkan@zappa.cx > Regression: No > > > I noticed when looking for other things that there are two neigh folders in > /proc/sys/net/ipv6 > > Reverting this commit removes the extra neigh folder: > > http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=commitdiff;h=bf36076a67db6d7423d09d861a072337866f0dd9 > > I don't know how to fix this. > I tried removing the ',' on the row '.child = empty,' (looking at the other > rows it did seem like a typo to me). > > This did not change anything that I could see though. > > Here is the commit I believe introduced the bug: > > --- a/net/ipv6/sysctl_net_ipv6.c > +++ b/net/ipv6/sysctl_net_ipv6.c > @@ -15,6 +15,8 @@ > #include <net/addrconf.h> > #include <net/inet_frag.h> > > +static struct ctl_table empty[1]; > + > static ctl_table ipv6_table_template[] = { > { > .procname = "route", > @@ -35,6 +37,12 @@ static ctl_table ipv6_table_template[] = { > .mode = 0644, > .proc_handler = proc_dointvec > }, > + { > + .procname = "neigh", > + .maxlen = 0, > + .mode = 0555, > + .child = empty, > + }, > { } > }; > > @@ -152,7 +160,6 @@ static struct ctl_table_header *ip6_base; > > int ipv6_static_sysctl_register(void) > { > - static struct ctl_table empty[1]; > ip6_base = register_sysctl_paths(net_ipv6_ctl_path, empty); > if (ip6_base == NULL) > return -ENOMEM; > Andrew Morton <akpm@linux-foundation.org> writes: > (switched to email. Please respond via emailed reply-to-all, not via the > bugzilla web interface). > > On Wed, 16 Mar 2011 22:06:34 GMT > bugzilla-daemon@bugzilla.kernel.org wrote: > >> https://bugzilla.kernel.org/show_bug.cgi?id=31232 >> >> Summary: /proc/sys/net/ipv6 has two neigh folders >> Product: Networking >> Version: 2.5 >> Kernel Version: 2.6.38 >> Platform: All >> OS/Version: Linux >> Tree: Mainline >> Status: NEW >> Severity: low >> Priority: P1 >> Component: IPV6 >> AssignedTo: yoshfuji@linux-ipv6.org >> ReportedBy: sunkan@zappa.cx >> Regression: No >> >> >> I noticed when looking for other things that there are two neigh folders in >> /proc/sys/net/ipv6 >> >> Reverting this commit removes the extra neigh folder: >> >> http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=commitdiff;h=bf36076a67db6d7423d09d861a072337866f0dd9 >> >> I don't know how to fix this. >> I tried removing the ',' on the row '.child = empty,' (looking at the other >> rows it did seem like a typo to me). >> >> This did not change anything that I could see though. >> >> Here is the commit I believe introduced the bug: Interesting. This is definitely a bug. I suspect it may be another symptom of the bug I was trying to fix. Something somewhere is messed up with the neigh directory. That extra neigh entry should serve as a mount point for any later neigh entries that are registered, so the change should be fine. I will see if I can make the time to look into this, as this new symptom looks as nasty as the use after free problems I was seeing earlier. Eric >> --- a/net/ipv6/sysctl_net_ipv6.c >> +++ b/net/ipv6/sysctl_net_ipv6.c >> @@ -15,6 +15,8 @@ >> #include <net/addrconf.h> >> #include <net/inet_frag.h> >> >> +static struct ctl_table empty[1]; >> + >> static ctl_table ipv6_table_template[] = { >> { >> .procname = "route", >> @@ -35,6 +37,12 @@ static ctl_table ipv6_table_template[] = { >> .mode = 0644, >> .proc_handler = proc_dointvec >> }, >> + { >> + .procname = "neigh", >> + .maxlen = 0, >> + .mode = 0555, >> + .child = empty, >> + }, >> { } >> }; >> >> @@ -152,7 +160,6 @@ static struct ctl_table_header *ip6_base; >> >> int ipv6_static_sysctl_register(void) >> { >> - static struct ctl_table empty[1]; >> ip6_base = register_sysctl_paths(net_ipv6_ctl_path, empty); >> if (ip6_base == NULL) >> return -ENOMEM; >> A patch referencing this bug report has been merged in v2.6.38-8876-g036a982: commit 9d2a8fa96a44ba242de3a6f56acaef7a40a97b97 Author: Eric W. Biederman <ebiederm@aristanetworks.com> Date: Mon Mar 21 18:23:34 2011 -0700 net ipv6: Fix duplicate /proc/sys/net/ipv6/neigh directory entries. |