user/sven/linux.git/net, branch v5.6.13

netfilter: nf_osf: avoid passing pointer to local var

2020-05-14T05:59:27Z

commit c165d57b552aaca607fa5daf3fb524a6efe3c5a3 upstream. gcc-10 points out that a code path exists where a pointer to a stack variable may be passed back to the caller: net/netfilter/nfnetlink_osf.c: In function 'nf_osf_hdr_ctx_init': cc1: warning: function may return address of local variable [-Wreturn-local-addr] net/netfilter/nfnetlink_osf.c:171:16: note: declared here 171 | struct tcphdr _tcph; | ^~~~~ I am not sure whether this can happen in practice, but moving the variable declaration into the callers avoids the problem. Fixes: 31a9c29210e2 ("netfilter: nf_osf: add struct nf_osf_hdr_ctx") Signed-off-by: Arnd Bergmann Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: nat: never update the UDP checksum when it's 0

2020-05-14T05:59:27Z

commit ea64d8d6c675c0bb712689b13810301de9d8f77a upstream. If the UDP header of a local VXLAN endpoint is NAT-ed, and the VXLAN device has disabled UDP checksums and enabled Tx checksum offloading, then the skb passed to udp_manip_pkt() has hdr->check == 0 (outer checksum disabled) and skb->ip_summed == CHECKSUM_PARTIAL (inner packet checksum offloaded). Because of the ->ip_summed value, udp_manip_pkt() tries to update the outer checksum with the new address and port, leading to an invalid checksum sent on the wire, as the original null checksum obviously didn't take the old address and port into account. So, we can't take ->ip_summed into account in udp_manip_pkt(), as it might not refer to the checksum we're acting on. Instead, we can base the decision to update the UDP checksum entirely on the value of hdr->check, because it's null if and only if checksum is disabled: * A fully computed checksum can't be 0, since a 0 checksum is represented by the CSUM_MANGLED_0 value instead. * A partial checksum can't be 0, since the pseudo-header always adds at least one non-zero value (the UDP protocol type 0x11) and adding more values to the sum can't make it wrap to 0 as the carry is then added to the wrapped number. * A disabled checksum uses the special value 0. The problem seems to be there from day one, although it was probably not visible before UDP tunnels were implemented. Fixes: 5b1158e909ec ("[NETFILTER]: Add NAT support for nf_conntrack") Signed-off-by: Guillaume Nault Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

batman-adv: Fix refcnt leak in batadv_v_ogm_process

2020-05-14T05:59:25Z

commit 6f91a3f7af4186099dd10fa530dd7e0d9c29747d upstream. batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns a reference of the neighbor object to "hardif_neigh" with increased refcount. When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling paths of batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the orig node and returns NULL, the refcnt increased by batadv_hardif_neigh_get() is not decreased, causing a refcnt leak. Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get() fails to get the orig node. Fixes: 9323158ef9f4 ("batman-adv: OGMv2 - implement originators logic") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman

batman-adv: Fix refcnt leak in batadv_store_throughput_override

2020-05-14T05:59:25Z

commit 6107c5da0fca8b50b4d3215e94d619d38cc4a18c upstream. batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(), which gets a batadv_hard_iface object from net_dev with increased refcnt and its reference is assigned to a local pointer 'hard_iface'. When batadv_store_throughput_override() returns, "hard_iface" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in one error path of batadv_store_throughput_override(). When batadv_parse_throughput() returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is not decreased, causing a refcnt leak. Fix this issue by jumping to "out" label when batadv_parse_throughput() returns NULL. Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman

batman-adv: Fix refcnt leak in batadv_show_throughput_override

2020-05-14T05:59:25Z

commit f872de8185acf1b48b954ba5bd8f9bc0a0d14016 upstream. batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(), which gets a batadv_hard_iface object from net_dev with increased refcnt and its reference is assigned to a local pointer 'hard_iface'. When batadv_show_throughput_override() returns, "hard_iface" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in the normal path of batadv_show_throughput_override(), which forgets to decrease the refcnt increased by batadv_hardif_get_by_netdev() before the function returns, causing a refcnt leak. Fix this issue by calling batadv_hardif_put() before the batadv_show_throughput_override() returns in the normal path. Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman

batman-adv: fix batadv_nc_random_weight_tq

2020-05-14T05:59:25Z

commit fd0c42c4dea54335967c5a86f15fc064235a2797 upstream. and change to pseudorandom numbers, as this is a traffic dithering operation that doesn't need crypto-grade. The previous code operated in 4 steps: 1. Generate a random byte 0 <= rand_tq <= 255 2. Multiply it by BATADV_TQ_MAX_VALUE - tq 3. Divide by 255 (= BATADV_TQ_MAX_VALUE) 4. Return BATADV_TQ_MAX_VALUE - rand_tq This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random value between 0/255 and 255/255. But! The intermediate value between steps 3 and 4 is stored in a u8 variable. So it's truncated, and most of the time, is less than 255, after which the division produces 0. Specifically, if tq is odd, the product is always even, and can never be 255. If tq is even, there's exactly one random byte value that will produce a product byte of 255. Thus, the return value is 255 (511/512 of the time) or 254 (1/512 of the time). If we assume that the truncation is a bug, and the code is meant to scale the input, a simpler way of looking at it is that it's returning a random value between tq and BATADV_TQ_MAX_VALUE, inclusive. Well, we have an optimized function for doing just that. Fixes: 3c12de9a5c75 ("batman-adv: network coding - code and transmit packets if possible") Signed-off-by: George Spelvin Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman

sctp: Fix bundling of SHUTDOWN with COOKIE-ACK

2020-05-14T05:59:20Z

commit 145cb2f7177d94bc54563ed26027e952ee0ae03c upstream. When we start shutdown in sctp_sf_do_dupcook_a(), we want to bundle the SHUTDOWN with the COOKIE-ACK to ensure that the peer receives them at the same time and in the correct order. This bundling was broken by commit 4ff40b86262b ("sctp: set chunk transport correctly when it's a new asoc"), which assigns a transport for the COOKIE-ACK, but not for the SHUTDOWN. Fix this by passing a reference to the COOKIE-ACK chunk as an argument to sctp_sf_do_9_2_start_shutdown() and onward to sctp_make_shutdown(). This way the SHUTDOWN chunk is assigned the same transport as the COOKIE-ACK chunk, which allows them to be bundled. In sctp_sf_do_9_2_start_shutdown(), the void *arg parameter was previously unused. Now that we're taking it into use, it must be a valid pointer to a chunk, or NULL. There is only one call site where it's not, in sctp_sf_autoclose_timer_expire(). Fix that too. Fixes: 4ff40b86262b ("sctp: set chunk transport correctly when it's a new asoc") Signed-off-by: Jere Leppänen Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

tipc: fix partial topology connection closure

2020-05-14T05:59:18Z

[ Upstream commit 980d69276f3048af43a045be2925dacfb898a7be ] When an application connects to the TIPC topology server and subscribes to some services, a new connection is created along with some objects - 'tipc_subscription' to store related data correspondingly... However, there is one omission in the connection handling that when the connection or application is orderly shutdown (e.g. via SIGQUIT, etc.), the connection is not closed in kernel, the 'tipc_subscription' objects are not freed too. This results in: - The maximum number of subscriptions (65535) will be reached soon, new subscriptions will be rejected; - TIPC module cannot be removed (unless the objects are somehow forced to release first); The commit fixes the issue by closing the connection if the 'recvmsg()' returns '0' i.e. when the peer is shutdown gracefully. It also includes the other unexpected cases. Acked-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: Tuong Lien Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sch_sfq: validate silly quantum values

2020-05-14T05:59:18Z

[ Upstream commit df4953e4e997e273501339f607b77953772e3559 ] syzbot managed to set up sfq so that q->scaled_quantum was zero, triggering an infinite loop in sfq_dequeue() More generally, we must only accept quantum between 1 and 2^18 - 7, meaning scaled_quantum must be in [1, 0x7FFF] range. Otherwise, we also could have a loop in sfq_dequeue() if scaled_quantum happens to be 0x8000, since slot->allot could indefinitely switch between 0 and 0x8000. Fixes: eeaeb068f139 ("sch_sfq: allow big packets and be fair") Signed-off-by: Eric Dumazet Reported-by: syzbot+0251e883fe39e7a0cb0a@syzkaller.appspotmail.com Cc: Jason A. Donenfeld Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sch_choke: avoid potential panic in choke_reset()

2020-05-14T05:59:18Z

[ Upstream commit 8738c85c72b3108c9b9a369a39868ba5f8e10ae0 ] If choke_init() could not allocate q->tab, we would crash later in choke_reset(). BUG: KASAN: null-ptr-deref in memset include/linux/string.h:366 [inline] BUG: KASAN: null-ptr-deref in choke_reset+0x208/0x340 net/sched/sch_choke.c:326 Write of size 8 at addr 0000000000000000 by task syz-executor822/7022 CPU: 1 PID: 7022 Comm: syz-executor822 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 __kasan_report.cold+0x5/0x4d mm/kasan/report.c:515 kasan_report+0x33/0x50 mm/kasan/common.c:625 check_memory_region_inline mm/kasan/generic.c:187 [inline] check_memory_region+0x141/0x190 mm/kasan/generic.c:193 memset+0x20/0x40 mm/kasan/common.c:85 memset include/linux/string.h:366 [inline] choke_reset+0x208/0x340 net/sched/sch_choke.c:326 qdisc_reset+0x6b/0x520 net/sched/sch_generic.c:910 dev_deactivate_queue.constprop.0+0x13c/0x240 net/sched/sch_generic.c:1138 netdev_for_each_tx_queue include/linux/netdevice.h:2197 [inline] dev_deactivate_many+0xe2/0xba0 net/sched/sch_generic.c:1195 dev_deactivate+0xf8/0x1c0 net/sched/sch_generic.c:1233 qdisc_graft+0xd25/0x1120 net/sched/sch_api.c:1051 tc_modify_qdisc+0xbab/0x1a00 net/sched/sch_api.c:1670 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5454 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362 ___sys_sendmsg+0x100/0x170 net/socket.c:2416 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 Fixes: 77e62da6e60c ("sch_choke: drop all packets in queue during reset") Signed-off-by: Eric Dumazet Reported-by: syzbot Cc: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman