kernel/net/ipv4/inet_hashtables.c, branch linux-5.1.y

net: dccp: fix kernel crash on module load

2018-12-24T23:27:56Z

Patch eedbbb0d98b2 "net: dccp: initialize (addr,port) ..." added calling to inet_hashinfo2_init() from dccp_init(). However, inet_hashinfo2_init() is marked as __init(), and thus the kernel panics when dccp is loaded as module. Removing __init() tag from inet_hashinfo2_init() is not feasible because it calls into __init functions in mm. This patch adds inet_hashinfo2_init_mod() function that can be called after the init phase is done; changes dccp_init() to call the new function; un-marks inet_hashinfo2_init() as exported. Fixes: eedbbb0d98b2 ("net: dccp: initialize (addr,port) ...") Reported-by: kernel test robot Signed-off-by: Peter Oskolkov Signed-off-by: David S. Miller

net: dccp: initialize (addr,port) listening hashtable

2018-12-18T07:11:48Z

Commit d9fbc7f6431f "net: tcp: prefer listeners bound to an address" removes port-only listener lookups. This caused segfaults in DCCP lookups because DCCP did not initialize the (addr,port) hashtable. This patch adds said initialization. The only non-trivial issue here is the size of the new hashtable. It seemed reasonable to make it match the size of the port-only hashtable (= INET_LHTABLE_SIZE) that was used previously. Other parameters to inet_hashinfo2_init() match those used in TCP. V2 changes: marked inet_hashinfo2_init as an exported symbol so that DCCP compiles when configured as a module. Tested: syzcaller issues fixed; the second patch in the patchset tests that DCCP lookups work correctly. Fixes: d9fbc7f6431f "net: tcp: prefer listeners bound to an address" Reported-by: syzcaller Signed-off-by: Peter Oskolkov Signed-off-by: David S. Miller

net: tcp: prefer listeners bound to an address

2018-12-14T23:55:20Z

A relatively common use case is to have several IPs configured on a host, and have different listeners for each of them. We would like to add a "catch all" listener on addr_any, to match incoming connections not served by any of the listeners bound to a specific address. However, port-only lookups can match addr_any sockets when sockets listening on specific addresses are present if so_reuseport flag is set. This patch eliminates lookups into port-only hashtable, as lookups by (addr,port) tuple are easily available. In addition, compute_score() is tweaked to _not_ match addr_any sockets to specific addresses, as hash collisions could result in the unwanted behavior described above. Tested: the patch compiles; full test in the last patch in this patchset. Existing reuseport_* selftests also pass. Suggested-by: Eric Dumazet Signed-off-by: Peter Oskolkov Signed-off-by: David S. Miller

net: ensure unbound stream socket to be chosen when not in a VRF

2018-11-08T00:12:38Z

The commit a04a480d4392 ("net: Require exact match for TCP socket lookups if dif is l3mdev") only ensures that the correct socket is selected for packets in a VRF. However, there is no guarantee that the unbound socket will be selected for packets when not in a VRF. By checking for a device match in compute_score() also for the case when there is no bound device and attaching a score to this, the unbound socket is selected. And if a failure is returned when there is no device match, this ensures that bound sockets are never selected, even if there is no unbound socket. Signed-off-by: Mike Manning Reviewed-by: David Ahern Tested-by: David Ahern Signed-off-by: David S. Miller

net: allow binding socket in a VRF when there's an unbound socket

2018-11-08T00:12:38Z

Change the inet socket lookup to avoid packets arriving on a device enslaved to an l3mdev from matching unbound sockets by removing the wildcard for non sk_bound_dev_if and instead relying on check against the secondary device index, which will be 0 when the input device is not enslaved to an l3mdev and so match against an unbound socket and not match when the input device is enslaved. Change the socket binding to take the l3mdev into account to allow an unbound socket to not conflict sockets bound to an l3mdev given the datapath isolation now guaranteed. Signed-off-by: Robert Shearman Signed-off-by: Mike Manning Reviewed-by: David Ahern Tested-by: David Ahern Signed-off-by: David S. Miller

mm: remove include/linux/bootmem.h

2018-10-31T15:54:16Z

Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include @@ @@ - #include + #include [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport Signed-off-by: Stephen Rothwell Acked-by: Michal Hocko Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Kroah-Hartman Cc: Guan Xuetao Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Jonas Bonn Cc: Jonathan Corbet Cc: Ley Foon Tan Cc: Mark Salter Cc: Martin Schwidefsky Cc: Matt Turner Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Paul Burton Cc: Richard Kuo Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Serge Semin Cc: Thomas Gleixner Cc: Tony Luck Cc: Vineet Gupta Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selection

2018-08-10T23:58:46Z

This patch allows a BPF_PROG_TYPE_SK_REUSEPORT bpf prog to select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY introduced in the earlier patch. "bpf_run_sk_reuseport()" will return -ECONNREFUSED when the BPF_PROG_TYPE_SK_REUSEPORT prog returns SK_DROP. The callers, in inet[6]_hashtable.c and ipv[46]/udp.c, are modified to handle this case and return NULL immediately instead of continuing the sk search from its hashtable. It re-uses the existing SO_ATTACH_REUSEPORT_EBPF setsockopt to attach BPF_PROG_TYPE_SK_REUSEPORT. The "sk_reuseport_attach_bpf()" will check if the attaching bpf prog is in the new SK_REUSEPORT or the existing SOCKET_FILTER type and then check different things accordingly. One level of "__reuseport_attach_prog()" call is removed. The "sk_unhashed() && ..." and "sk->sk_reuseport_cb" tests are pushed back to "reuseport_attach_prog()" in sock_reuseport.c. sock_reuseport.c seems to have more knowledge on those test requirements than filter.c. In "reuseport_attach_prog()", after new_prog is attached to reuse->prog, the old_prog (if any) is also directly freed instead of returning the old_prog to the caller and asking the caller to free. The sysctl_optmem_max check is moved back to the "sk_reuseport_attach_filter()" and "sk_reuseport_attach_bpf()". As of other bpf prog types, the new BPF_PROG_TYPE_SK_REUSEPORT is only bounded by the usual "bpf_prog_charge_memlock()" during load time instead of bounded by both bpf_prog_charge_memlock and sysctl_optmem_max. Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann

bpf: Introduce BPF_PROG_TYPE_SK_REUSEPORT

2018-08-10T23:58:46Z

This patch adds a BPF_PROG_TYPE_SK_REUSEPORT which can select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY. Like other non SK_FILTER/CGROUP_SKB program, it requires CAP_SYS_ADMIN. BPF_PROG_TYPE_SK_REUSEPORT introduces "struct sk_reuseport_kern" to store the bpf context instead of using the skb->cb[48]. At the SO_REUSEPORT sk lookup time, it is in the middle of transiting from a lower layer (ipv4/ipv6) to a upper layer (udp/tcp). At this point, it is not always clear where the bpf context can be appended in the skb->cb[48] to avoid saving-and-restoring cb[]. Even putting aside the difference between ipv4-vs-ipv6 and udp-vs-tcp. It is not clear if the lower layer is only ipv4 and ipv6 in the future and will it not touch the cb[] again before transiting to the upper layer. For example, in udp_gro_receive(), it uses the 48 byte NAPI_GRO_CB instead of IP[6]CB and it may still modify the cb[] after calling the udp[46]_lib_lookup_skb(). Because of the above reason, if sk->cb is used for the bpf ctx, saving-and-restoring is needed and likely the whole 48 bytes cb[] has to be saved and restored. Instead of saving, setting and restoring the cb[], this patch opts to create a new "struct sk_reuseport_kern" and setting the needed values in there. The new BPF_PROG_TYPE_SK_REUSEPORT and "struct sk_reuseport_(kern|md)" will serve all ipv4/ipv6 + udp/tcp combinations. There is no protocol specific usage at this point and it is also inline with the current sock_reuseport.c implementation (i.e. no protocol specific requirement). In "struct sk_reuseport_md", this patch exposes data/data_end/len with semantic similar to other existing usages. Together with "bpf_skb_load_bytes()" and "bpf_skb_load_bytes_relative()", the bpf prog can peek anywhere in the skb. The "bind_inany" tells the bpf prog that the reuseport group is bind-ed to a local INANY address which cannot be learned from skb. The new "bind_inany" is added to "struct sock_reuseport" which will be used when running the new "BPF_PROG_TYPE_SK_REUSEPORT" bpf prog in order to avoid repeating the "bind INANY" test on "sk_v6_rcv_saddr/sk->sk_rcv_saddr" every time a bpf prog is run. It can only be properly initialized when a "sk->sk_reuseport" enabled sk is adding to a hashtable (i.e. during "reuseport_alloc()" and "reuseport_add_sock()"). The new "sk_select_reuseport()" is the main helper that the bpf prog will use to select a SO_REUSEPORT sk. It is the only function that can use the new BPF_MAP_TYPE_REUSEPORT_ARRAY. As mentioned in the earlier patch, the validity of a selected sk is checked in run time in "sk_select_reuseport()". Doing the check in verification time is difficult and inflexible (consider the map-in-map use case). The runtime check is to compare the selected sk's reuseport_id with the reuseport_id that we want. This helper will return -EXXX if the selected sk cannot serve the incoming request (e.g. reuseport_id not match). The bpf prog can decide if it wants to do SK_DROP as its discretion. When the bpf prog returns SK_PASS, the kernel will check if a valid sk has been selected (i.e. "reuse_kern->selected_sk != NULL"). If it does , it will use the selected sk. If not, the kernel will select one from "reuse->socks[]" (as before this patch). The SK_DROP and SK_PASS handling logic will be in the next patch. Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann

net/tcp: Fix socket lookups with SO_BINDTODEVICE

2018-06-19T23:03:06Z

Similar to 69678bcd4d2d ("udp: fix SO_BINDTODEVICE"), TCP socket lookups need to fail if dev_match is not true. Currently, a packet to a given port can match a socket bound to device when it should not. In the VRF case, this causes the lookup to hit a VRF socket and not a global socket resulting in a response trying to go through the VRF when it should not. Fixes: 3fa6f616a7a4d ("net: ipv4: add second dif to inet socket lookups") Fixes: 4297a0ef08572 ("net: ipv6: add second dif to inet6 socket lookups") Reported-by: Lou Berger Diagnosed-by: Renato Westphal Tested-by: Renato Westphal Signed-off-by: David Ahern Signed-off-by: David S. Miller

inet: Avoid unitialized variable warning in inet_unhash()

2018-02-01T14:48:42Z

With gcc-4.1.2: net/ipv4/inet_hashtables.c: In function ‘inet_unhash’: net/ipv4/inet_hashtables.c:628: warning: ‘ilb’ may be used uninitialized in this function While this is a false positive, it can easily be avoided by using the pointer itself as the canary variable. Signed-off-by: Geert Uytterhoeven Acked-by: Arnd Bergmann Signed-off-by: David S. Miller