kernel/linux.git/net/ipv6/mcast.c, branch linux-4.13.y

net, ipv6: convert ifmcaddr6.mca_refcnt from atomic_t to refcount_t

2017-07-04T08:29:04+00:00

refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller

networking: make skb_put & friends return void pointers

2017-06-16T15:48:39+00:00

It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions (skb_put, __skb_put and pskb_put) return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_put, __skb_put }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_put, __skb_put }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) which actually doesn't cover pskb_put since there are only three users overall. A handful of stragglers were converted manually, notably a macro in drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many instances in net/bluetooth/hci_sock.c. In the former file, I also had to fix one whitespace problem spatch introduced. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

networking: introduce and use skb_put_data()

2017-06-16T15:48:37+00:00

A common pattern with skb_put() is to just want to memcpy() some data into the new space, introduce skb_put_data() for this. An spatch similar to the one for skb_put_zero() converts many of the places using it: @@ identifier p, p2; expression len, skb, data; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_data(skb, data, len); | -p = (t)skb_put(skb, len); +p = skb_put_data(skb, data, len); ) ( p2 = (t2)p; -memcpy(p2, data, len); | -memcpy(p, data, len); ) @@ type t, t2; identifier p, p2; expression skb, data; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); ) ( p2 = (t2)p; -memcpy(p2, data, sizeof(*p)); | -memcpy(p, data, sizeof(*p)); ) @@ expression skb, len, data; @@ -memcpy(skb_put(skb, len), data, len); +skb_put_data(skb, data, len); (again, manually post-processed to retain some comments) Reviewed-by: Stephen Hemminger Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

networking: convert many more places to skb_put_zero()

2017-06-16T15:48:35+00:00

There were many places that my previous spatch didn't find, as pointed out by yuan linyu in various patches. The following spatch found many more and also removes the now unnecessary casts: @@ identifier p, p2; expression len; expression skb; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_zero(skb, len); | -p = (t)skb_put(skb, len); +p = skb_put_zero(skb, len); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, len); | -memset(p, 0, len); ) @@ type t, t2; identifier p, p2; expression skb; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, sizeof(*p)); | -memset(p, 0, sizeof(*p)); ) @@ expression skb, len; @@ -memset(skb_put(skb, len), 0, len); +skb_put_zero(skb, len); Apply it to the tree (with one manual fixup to keep the comment in vxlan.c, which spatch removed.) Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

ipv6: add support for NETDEV_RESEND_IGMP event

2017-03-29T05:02:21+00:00

This patch adds support for NETDEV_RESEND_IGMP event similar to how it works for IPv4. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller

igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()

2017-02-09T21:43:45+00:00

In function igmpv3/mld_add_delrec() we allocate pmc and put it in idev->mc_tomb, so we should free it when we don't need it in del_delrec(). But I removed kfree(pmc) incorrectly in latest two patches. Now fix it. Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when ...") Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when ...") Reported-by: Daniel Borkmann Signed-off-by: Hangbin Liu Signed-off-by: David S. Miller

mld: do not remove mld souce list info when set link down

2017-01-16T17:44:59+00:00

This is an IPv6 version of commit 24803f38a5c0 ("igmp: do not remove igmp souce list..."). In mld_del_delrec(), we will restore back all source filter info instead of flush them. Move mld_clear_delrec() from ipv6_mc_down() to ipv6_mc_destroy_dev() since we should not remove source list info when set link down. Remove igmp6_group_dropped() in ipv6_mc_destroy_dev() since we have called it in ipv6_mc_down(). Also clear all source info after igmp6_group_dropped() instead of in it because ipv6_mc_down() will call igmp6_group_dropped(). Signed-off-by: Hangbin Liu Signed-off-by: David S. Miller

ipv6: fix a potential deadlock in do_ipv6_setsockopt()

2016-10-21T15:29:02+00:00

Baozeng reported this deadlock case: CPU0 CPU1 ---- ---- lock([ 165.136033] sk_lock-AF_INET6); lock([ 165.136033] rtnl_mutex); lock([ 165.136033] sk_lock-AF_INET6); lock([ 165.136033] rtnl_mutex); Similar to commit 87e9f0315952 ("ipv4: fix a potential deadlock in mcast getsockopt() path") this is due to we still have a case, ipv6_sock_mc_close(), where we acquire sk_lock before rtnl_lock. Close this deadlock with the similar solution, that is always acquire rtnl lock first. Fixes: baf606d9c9b1 ("ipv4,ipv6: grab rtnl before locking the socket") Reported-by: Baozeng Ding Tested-by: Baozeng Ding Cc: Marcelo Ricardo Leitner Signed-off-by: Cong Wang Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

net/multicast: should not send source list records when have filter mode change

2016-08-08T23:04:39+00:00

Based on RFC3376 5.1 and RFC3810 6.1 If the per-interface listening change that triggers the new report is a filter mode change, then the next [Robustness Variable] State Change Reports will include a Filter Mode Change Record. This applies even if any number of source list changes occur in that period. Old State New State State Change Record Sent --------- --------- ------------------------ INCLUDE (A) EXCLUDE (B) TO_EX (B) EXCLUDE (A) INCLUDE (B) TO_IN (B) So we should not send source-list change if there is a filter-mode change. Here are two scenarios: 1. Group deleted and filter mode is EXCLUDE, which means we need send a TO_IN { }. 2. Not group deleted, but has pcm->crcount, which means we need send a normal filter-mode-change. At the same time, if the type is ALLOW or BLOCK, and have psf->sf_crcount, we stop add records and decrease sf_crcount directly Reference: https://www.ietf.org/mail-archive/web/magma/current/msg01274.html Signed-off-by: Hangbin Liu Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

mld, igmp: Fix reserved tailroom calculation

2016-03-03T20:41:07+00:00

The current reserved_tailroom calculation fails to take hlen and tlen into account. skb: [__hlen__|__data____________|__tlen___|__extra__] ^ ^ head skb_end_offset In this representation, hlen + data + tlen is the size passed to alloc_skb. "extra" is the extra space made available in __alloc_skb because of rounding up by kmalloc. We can reorder the representation like so: [__hlen__|__data____________|__extra__|__tlen___] ^ ^ head skb_end_offset The maximum space available for ip headers and payload without fragmentation is min(mtu, data + extra). Therefore, reserved_tailroom = data + extra + tlen - min(mtu, data + extra) = skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen) = skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen) Compare the second line to the current expression: reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset) and we can see that hlen and tlen are not taken into account. The min() in the third line can be expanded into: if mtu < skb_tailroom - tlen: reserved_tailroom = skb_tailroom - mtu else: reserved_tailroom = tlen Depending on hlen, tlen, mtu and the number of multicast address records, the current code may output skbs that have less tailroom than dev->needed_tailroom or it may output more skbs than needed because not all space available is used. Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs") Signed-off-by: Benjamin Poirier Acked-by: Hannes Frederic Sowa Acked-by: Daniel Borkmann Signed-off-by: David S. Miller