Commit 530903dd90 ("ip: fix igmp parsing when iface is long") uses
variable len to keep trailing colon from interface name comparison. This
variable is local to loop body but we set it in one pass and use it in
following one(s) so that we are actually using (pseudo)random length for
comparison. This became apparent since commit b48a1161f5 ("ipmaddr: Avoid
accessing uninitialized data") always initializes len to zero so that the
name comparison is always true. As a result, "ip maddr show dev eth0" shows
IPv4 multicast addresses for all interfaces.
Instead of keeping the length, let's simply replace the trailing colon with
a null byte. The bonus is that we get correct interface name in ma.name.
Fixes: 530903dd90 ("ip: fix igmp parsing when iface is long")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Phil Sutter <phil@nwl.cc>
Acked-by: Petr Vorel <pvorel@suse.cz>
The original problem was that something like:
| strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
might leave ifr.ifr_name unterminated if length of *argv exceeds
IFNAMSIZ. In order to fix this, I thought about replacing all those
cases with (equivalent) calls to snprintf() or even introducing
strlcpy(). But as Ulrich Drepper correctly pointed out when rejecting
the latter from being added to glibc, truncating a string without
notifying the user is not to be considered good practice. So let's
excercise what he suggested and reject empty, overlong or otherwise
invalid interface names right from the start - this way calls to
strncpy() like shown above become safe and the user has a chance to
reconsider what he was trying to do.
Note that this doesn't add calls to check_ifname() to all places where
user supplied interface name is parsed. In many cases, the interface
must exist already and is therefore looked up using ll_name_to_index(),
so if_nametoindex() will perform the necessary checks already.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Entries with long vhost names in /proc/net/igmp have no whitespace
between name and colon, so sscanf() adds it to vhost and
'ip maddr show iface' doesn't include inet result.
Signed-off-by: Petr Vorel <pvorel@suse.cz>
This big patch was compiled by vimgrepping for memset calls and changing
to C99 initializer if applicable. One notable exception is the
initialization of union bpf_attr in tc/tc_bpf.c: changing it would break
for older gcc versions (at least <=3.4.6).
Calls to memset for struct rtattr pointer fields for parse_rtattr*()
were just dropped since they are not needed.
The changes here allowed the compiler to discover some unused variables,
so get rid of them, too.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
There are only three users which require it to be reentrant, the rest is
fine without. Instead, provide a reentrant format_host_r() for users
which need it.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Device names that match "help" or a prefix thereof should be allowed anywhere
a device name can be used. Note that a suitable keyword ("dev" or "name", the
latter for "ip tunnel") has to be used in these cases to resolve ambiguities.
Signed-off-by: Christoph Schulz <develop@kristov.de>
Reported-by: Leonhard Preis <leonhard@pre.is>
Reported-by: Wilhelm Wijkander <lists@0x5e.se>
If the continue is taken, then there is a memory leak.
https://bugzilla.novell.com/show_bug.cgi?id=538996
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Brandon Philips <bphilips@suse.de>
“ip maddr show” on an infiniband address causes a stack corruption
because the length of the address for Infiniband (20 bytes, as
described in kernel doc Documentation/infiniband/ipoib.txt) does not
fit on the 16 bytes of the field in which it gets stored.
The proposed patch increases the size of the hardware address from 4
__u32 to 8 and also adds a check to avoid overriding the available
size while parsing the hardware address.
This bug affects current upstream code AFAICT.
Hope this helps,
Cheers,
Olivier.
“ip maddr show ib0” causes a stack corruption because the length of the address
for Infiniband (20 see kernel doc Documentation/infiniband/ipoib.txt) does not
fit on the 16 bytes of the field in which it gets stored.
The proposed patch increases the size of the hardware address from 4 u32 to 8
and adds a check to avoid overriding the available size while parsing the
hardware address.
