linux.git/net/ipv4/fib_semantics.c, branch v6.5

neighbour: switch to standard rcu, instead of rcu_bh

2023-03-22T04:32:18+00:00

rcu_bh is no longer a win, especially for objects freed
with standard call_rcu().

Switch neighbour code to no longer disable BH when not necessary.

Signed-off-by: Eric Dumazet 
Signed-off-by: Jakub Kicinski

neighbour: annotate lockless accesses to n->nud_state

2023-03-15T07:37:32+00:00

We have many lockless accesses to n->nud_state.

Before adding another one in the following patch,
add annotations to readers and writers.

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Reviewed-by: Martin KaFai Lau 
Signed-off-by: Jakub Kicinski

ipv4: prevent potential spectre v1 gadget in fib_metrics_match()

2023-01-24T05:37:39+00:00

if (!type)
        continue;
    if (type > RTAX_MAX)
        return false;
    ...
    fi_val = fi->fib_metrics->metrics[type - 1];

@type being used as an array index, we need to prevent
cpu speculation or risk leaking kernel memory content.

Fixes: 5f9ae3d9e7e4 ("ipv4: do metrics match when looking up and deleting a route")
Signed-off-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20230120133140.3624204-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

ipv4: Fix incorrect route flushing when source address is deleted

2022-12-07T04:34:43+00:00

Cited commit added the table ID to the FIB info structure, but did not
prevent structures with different table IDs from being consolidated.
This can lead to routes being flushed from a VRF when an address is
deleted from a different VRF.

Fix by taking the table ID into account when looking for a matching FIB
info. This is already done for FIB info structures backed by a nexthop
object in fib_find_info_nh().

Add test cases that fail before the fix:

 # ./fib_tests.sh -t ipv4_del_addr

 IPv4 delete address route tests
     Regular FIB info
     TEST: Route removed from VRF when source address deleted            [ OK ]
     TEST: Route in default VRF not removed                              [ OK ]
     TEST: Route removed in default VRF when source address deleted      [ OK ]
     TEST: Route in VRF is not removed by address delete                 [ OK ]
     Identical FIB info with different table ID
     TEST: Route removed from VRF when source address deleted            [FAIL]
     TEST: Route in default VRF not removed                              [ OK ]
 RTNETLINK answers: File exists
     TEST: Route removed in default VRF when source address deleted      [ OK ]
     TEST: Route in VRF is not removed by address delete                 [FAIL]

 Tests passed:   6
 Tests failed:   2

And pass after:

 # ./fib_tests.sh -t ipv4_del_addr

 IPv4 delete address route tests
     Regular FIB info
     TEST: Route removed from VRF when source address deleted            [ OK ]
     TEST: Route in default VRF not removed                              [ OK ]
     TEST: Route removed in default VRF when source address deleted      [ OK ]
     TEST: Route in VRF is not removed by address delete                 [ OK ]
     Identical FIB info with different table ID
     TEST: Route removed from VRF when source address deleted            [ OK ]
     TEST: Route in default VRF not removed                              [ OK ]
     TEST: Route removed in default VRF when source address deleted      [ OK ]
     TEST: Route in VRF is not removed by address delete                 [ OK ]

 Tests passed:   8
 Tests failed:   0

Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs")
Signed-off-by: Ido Schimmel 
Reviewed-by: David Ahern 
Signed-off-by: Jakub Kicinski

ipv4: Fix route deletion when nexthop info is not specified

2022-11-29T00:56:04+00:00

When the kernel receives a route deletion request from user space it
tries to delete a route that matches the route attributes specified in
the request.

If only prefix information is specified in the request, the kernel
should delete the first matching FIB alias regardless of its associated
FIB info. However, an error is currently returned when the FIB info is
backed by a nexthop object:

 # ip nexthop add id 1 via 192.0.2.2 dev dummy10
 # ip route add 198.51.100.0/24 nhid 1
 # ip route del 198.51.100.0/24
 RTNETLINK answers: No such process

Fix by matching on such a FIB info when legacy nexthop attributes are
not specified in the request. An earlier check already covers the case
where a nexthop ID is specified in the request.

Add tests that cover these flows. Before the fix:

 # ./fib_nexthops.sh -t ipv4_fcnal
 ...
 TEST: Delete route when not specifying nexthop attributes           [FAIL]

 Tests passed:  11
 Tests failed:   1

After the fix:

 # ./fib_nexthops.sh -t ipv4_fcnal
 ...
 TEST: Delete route when not specifying nexthop attributes           [ OK ]

 Tests passed:  12
 Tests failed:   0

No regressions in other tests:

 # ./fib_nexthops.sh
 ...
 Tests passed: 228
 Tests failed:   0

 # ./fib_tests.sh
 ...
 Tests passed: 186
 Tests failed:   0

Cc: stable@vger.kernel.org
Reported-by: Jonas Gorski 
Tested-by: Jonas Gorski 
Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects")
Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning")
Fixes: 61b91eb33a69 ("ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference")
Signed-off-by: Ido Schimmel 
Reviewed-by: Nikolay Aleksandrov 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20221124210932.2470010-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski

Revert "ip: fix dflt addr selection for connected nexthop"

2022-10-27T17:17:36+00:00

This reverts commit 747c14307214b55dbd8250e1ab44cad8305756f1.

As explained by Julian, nhc_scope is related to nhc_gw, not to the route.
Revert the original patch. The initial problem is fixed differently in the
next commit.

Link: https://lore.kernel.org/netdev/6c8a44ba-c2d5-cdf-c5c7-5baf97cba38@ssi.bg/
Signed-off-by: Nicolas Dichtel 
Reviewed-by: Julian Anastasov 
Signed-off-by: Jakub Kicinski

ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference

2022-10-07T07:47:08+00:00

Gwangun Jung reported a slab-out-of-bounds access in fib_nh_match:
    fib_nh_match+0xf98/0x1130 linux-6.0-rc7/net/ipv4/fib_semantics.c:961
    fib_table_delete+0x5f3/0xa40 linux-6.0-rc7/net/ipv4/fib_trie.c:1753
    inet_rtm_delroute+0x2b3/0x380 linux-6.0-rc7/net/ipv4/fib_frontend.c:874

Separate nexthop objects are mutually exclusive with the legacy
multipath spec. Fix fib_nh_match to return if the config for the
to be deleted route contains a multipath spec while the fib_info
is using a nexthop object.

Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects")
Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning")
Reported-by: Gwangun Jung 
Signed-off-by: David Ahern 
Reviewed-by: Ido Schimmel 
Tested-by: Ido Schimmel 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-07-21T20:03:39+00:00

No conflicts.

Signed-off-by: Jakub Kicinski

ipv4: Fix a data-race around sysctl_fib_multipath_use_neigh.

2022-07-20T09:14:49+00:00

While reading sysctl_fib_multipath_use_neigh, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: a6db4494d218 ("net: ipv4: Consider failed nexthops in multipath routes")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-07-14T22:27:35+00:00

include/net/sock.h
  310731e2f161 ("net: Fix data-races around sysctl_mem.")
  e70f3c701276 ("Revert "net: set SK_MEM_QUANTUM to 4096"")
https://lore.kernel.org/all/20220711120211.7c8b7cba@canb.auug.org.au/

net/ipv4/fib_semantics.c
  747c14307214 ("ip: fix dflt addr selection for connected nexthop")
  d62607c3fe45 ("net: rename reference+tracking helpers")

net/tls/tls.h
include/net/tls.h
  3d8c51b25a23 ("net/tls: Check for errors in tls_device_init")
  587903142308 ("tls: create an internal header")

Signed-off-by: Jakub Kicinski