Use the new helper as a step to deal with potential dst->dev races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some lwtunnels have a dst cache for post-transformation dst.
If the packet destination did not change we may end up recording
a reference to the lwtunnel in its own cache, and the lwtunnel
state will never be freed.
Discovered by the ioam6.sh test, kmemleak was recently fixed
to catch per-cpu memory leaks. I'm not sure if rpl and seg6
can actually hit this, but in principle I don't see why not.
Fixes: 8cb3bf8bff ("ipv6: ioam: Add support for the ip6ip6 encapsulation")
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250130031519.2716843-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch mitigates the two-reallocations issue with rpl_iptunnel by
providing the dst_entry (in the cache) to the first call to
skb_cow_head(). As a result, the very first iteration would still
trigger two reallocations (i.e., empty cache), while next iterations
would only trigger a single reallocation.
Performance tests before/after applying this patch, which clearly shows
there is no impact (it even shows improvement):
- before: https://ibb.co/nQJhqwc
- after: https://ibb.co/4ZvW6wV
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Cc: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Free the skb before returning from rpl_input when skb_cow_head() fails.
Use a "drop" label and goto instructions.
Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240911174557.11536-1-justin.iurman@uliege.be
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As explained in commit 1378817486 ("tipc: block BH
before using dst_cache"), net/core/dst_cache.c
helpers need to be called with BH disabled.
Disabling preemption in rpl_output() is not good enough,
because rpl_output() is called from process context,
lwtunnel_output() only uses rcu_read_lock().
We might be interrupted by a softirq, re-enter rpl_output()
and corrupt dst_cache data structures.
Fix the race by using local_bh_disable() instead of
preempt_disable().
Apply a similar change in rpl_input().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Aring <aahringo@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240531132636.2637995-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RPL code has a pattern where skb_dst_drop() is called before
ip6_route_input().
However, ip6_route_input() calls skb_dst_drop() internally,
so we need not call skb_dst_drop() before ip6_route_input().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230710213511.5364-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Zero-length arrays are deprecated[1]. Replace struct ipv6_rpl_sr_hdr's
"segments" union of 0-length arrays with flexible arrays. Detected with
GCC 13, using -fstrict-flex-arrays=3:
In function 'rpl_validate_srh',
inlined from 'rpl_build_state' at ../net/ipv6/rpl_iptunnel.c:96:7:
../net/ipv6/rpl_iptunnel.c:60:28: warning: array subscript <unknown> is outside array bounds of 'struct in6_addr[0]' [-Warray-bounds=]
60 | if (ipv6_addr_type(&srh->rpl_segaddr[srh->segments_left - 1]) &
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../include/net/rpl.h:12,
from ../net/ipv6/rpl_iptunnel.c:13:
../include/uapi/linux/rpl.h: In function 'rpl_build_state':
../include/uapi/linux/rpl.h:40:33: note: while referencing 'addr'
40 | struct in6_addr addr[0];
| ^~~~
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230105221533.never.711-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/ipv6/rpl_iptunnel.c:15: warning: cannot understand function prototype: 'struct rpl_iptunnel_encap '
The header on the file containing the author copyright message uses
kerneldoc /** opener. This confuses the parser when it gets to
struct rpl_iptunnel_encap {
struct ipv6_rpl_sr_hdr srh[0];
};
Similarly:
net//ipv6/rpl.c:10: warning: Function parameter or member 'x' not described in 'IPV6_PFXTAIL_LEN'
where IPV6_PFXTAIL_LEN is a macro definition, not a function.
Convert the header comments to a plain /* comment.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20201028013123.931816-1-andrew@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes. Also, remove unnecessary
function ipv6_rpl_srh_alloc_size() and replace kzalloc() with kcalloc(),
which has a 2-factor argument form for multiplication.
This code was detected with the help of Coccinelle and, audited and
fixed manually.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable err is being initialized with a value that is never
read and it is being updated later with a new value. The initialization
is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case memory resources for buf were allocated, release them before
return.
Addresses-Coverity-ID: 1492011 ("Resource leak")
Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds functionality to configure routes for RPL source routing
functionality. There is no IPIP functionality yet implemented which can
be added later when the cases when to use IPv6 encapuslation comes more
clear.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
