user/sven/linux.git/net, branch v5.4-rc2

nfc: fix memory leak in llcp_sock_bind()

2019-10-05T01:31:36Z

sysbot reported a memory leak after a bind() has failed. While we are at it, abort the operation if kmemdup() has failed. BUG: memory leak unreferenced object 0xffff888105d83ec0 (size 32): comm "syz-executor067", pid 7207, jiffies 4294956228 (age 19.430s) hex dump (first 32 bytes): 00 69 6c 65 20 72 65 61 64 00 6e 65 74 3a 5b 34 .ile read.net:[4 30 32 36 35 33 33 30 39 37 5d 00 00 00 00 00 00 026533097]...... backtrace: [<0000000036bac473>] kmemleak_alloc_recursive /./include/linux/kmemleak.h:43 [inline] [<0000000036bac473>] slab_post_alloc_hook /mm/slab.h:522 [inline] [<0000000036bac473>] slab_alloc /mm/slab.c:3319 [inline] [<0000000036bac473>] __do_kmalloc /mm/slab.c:3653 [inline] [<0000000036bac473>] __kmalloc_track_caller+0x169/0x2d0 /mm/slab.c:3670 [<000000000cd39d07>] kmemdup+0x27/0x60 /mm/util.c:120 [<000000008e57e5fc>] kmemdup /./include/linux/string.h:432 [inline] [<000000008e57e5fc>] llcp_sock_bind+0x1b3/0x230 /net/nfc/llcp_sock.c:107 [<000000009cb0b5d3>] __sys_bind+0x11c/0x140 /net/socket.c:1647 [<00000000492c3bbc>] __do_sys_bind /net/socket.c:1658 [inline] [<00000000492c3bbc>] __se_sys_bind /net/socket.c:1656 [inline] [<00000000492c3bbc>] __x64_sys_bind+0x1e/0x30 /net/socket.c:1656 [<0000000008704b2a>] do_syscall_64+0x76/0x1a0 /arch/x86/entry/common.c:296 [<000000009f4c57a4>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 30cc4587659e ("NFC: Move LLCP code to the NFC top level diirectory") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller

sch_dsmark: fix potential NULL deref in dsmark_init()

2019-10-05T01:28:30Z

Make sure TCA_DSMARK_INDICES was provided by the user. syzbot reported : kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8799 Comm: syz-executor235 Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:nla_get_u16 include/net/netlink.h:1501 [inline] RIP: 0010:dsmark_init net/sched/sch_dsmark.c:364 [inline] RIP: 0010:dsmark_init+0x193/0x640 net/sched/sch_dsmark.c:339 Code: 85 db 58 0f 88 7d 03 00 00 e8 e9 1a ac fb 48 8b 9d 70 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 ca RSP: 0018:ffff88809426f3b8 EFLAGS: 00010247 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff85c6eb09 RDX: 0000000000000000 RSI: ffffffff85c6eb17 RDI: 0000000000000004 RBP: ffff88809426f4b0 R08: ffff88808c4085c0 R09: ffffed1015d26159 R10: ffffed1015d26158 R11: ffff8880ae930ac7 R12: ffff8880a7e96940 R13: dffffc0000000000 R14: ffff88809426f8c0 R15: 0000000000000000 FS: 0000000001292880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 000000008ca1b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_create+0x4ee/0x1210 net/sched/sch_api.c:1237 tc_modify_qdisc+0x524/0x1c50 net/sched/sch_api.c:1653 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5223 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440369 Fixes: 758cc43c6d73 ("[PKT_SCHED]: Fix dsmark to apply changes consistent") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller

ipv6: Handle missing host route in __ipv6_ifa_notify

2019-10-05T01:08:58Z

Rajendra reported a kernel panic when a link was taken down: [ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8 [ 6870.271856] IP: [] __ipv6_ifa_notify+0x154/0x290 [ 6870.570501] Call Trace: [ 6870.573238] [] ? ipv6_ifa_notify+0x26/0x40 [ 6870.579665] [] ? addrconf_dad_completed+0x4c/0x2c0 [ 6870.586869] [] ? ipv6_dev_mc_inc+0x196/0x260 [ 6870.593491] [] ? addrconf_dad_work+0x10a/0x430 [ 6870.600305] [] ? __switch_to_asm+0x34/0x70 [ 6870.606732] [] ? process_one_work+0x18a/0x430 [ 6870.613449] [] ? worker_thread+0x4d/0x490 [ 6870.619778] [] ? process_one_work+0x430/0x430 [ 6870.626495] [] ? kthread+0xd9/0xf0 [ 6870.632145] [] ? __switch_to_asm+0x34/0x70 [ 6870.638573] [] ? kthread_park+0x60/0x60 [ 6870.644707] [] ? ret_from_fork+0x57/0x70 [ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0 addrconf_dad_work is kicked to be scheduled when a device is brought up. There is a race between addrcond_dad_work getting scheduled and taking the rtnl lock and a process taking the link down (under rtnl). The latter removes the host route from the inet6_addr as part of addrconf_ifdown which is run for NETDEV_DOWN. The former attempts to use the host route in __ipv6_ifa_notify. If the down event removes the host route due to the race to the rtnl, then the BUG listed above occurs. Since the DAD sequence can not be aborted, add a check for the missing host route in __ipv6_ifa_notify. The only way this should happen is due to the previously mentioned race. The host route is created when the address is added to an interface; it is only removed on a down event where the address is kept. Add a warning if the host route is missing AND the device is up; this is a situation that should never happen. Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Reported-by: Rajendra Dendukuri Signed-off-by: David Ahern Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

net: ipv4: avoid mixed n_redirects and rate_tokens usage

2019-10-05T00:27:04Z

Since commit c09551c6ff7f ("net: ipv4: use a dedicated counter for icmp_v4 redirect packets") we use 'n_redirects' to account for redirect packets, but we still use 'rate_tokens' to compute the redirect packets exponential backoff. If the device sent to the relevant peer any ICMP error packet after sending a redirect, it will also update 'rate_token' according to the leaking bucket schema; typically 'rate_token' will raise above BITS_PER_LONG and the redirect packets backoff algorithm will produce undefined behavior. Fix the issue using 'n_redirects' to compute the exponential backoff in ip_rt_send_redirect(). Note that we still clear rate_tokens after a redirect silence period, to avoid changing an established behaviour. The root cause predates git history; before the mentioned commit in the critical scenario, the kernel stopped sending redirects, after the mentioned commit the behavior more randomic. Reported-by: Xiumei Mu Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: c09551c6ff7f ("net: ipv4: use a dedicated counter for icmp_v4 redirect packets") Signed-off-by: Paolo Abeni Acked-by: Lorenzo Bianconi Signed-off-by: David S. Miller

Revert "ipv6: Handle race in addrconf_dad_work"

2019-10-04T21:31:10Z

This reverts commit a3ce2a21bb8969ae27917281244fa91bf5f286d7. Eric reported tests failings with commit. After digging into it, the bottom line is that the DAD sequence is not to be messed with. There are too many cases that are expected to proceed regardless of whether a device is up. Revert the patch and I will send a different solution for the problem Rajendra reported. Signed-off-by: David Ahern Cc: Eric Dumazet Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

net: make sock_prot_memory_pressure() return "const char *"

2019-10-04T21:30:23Z

This function returns string literals which are "const char *". Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller

tcp: fix slab-out-of-bounds in tcp_zerocopy_receive()

2019-10-03T19:05:34Z

Apparently a refactoring patch brought a bug, that was caught by syzbot [1] Original code was correct, do not try to be smarter than the compiler :/ [1] BUG: KASAN: slab-out-of-bounds in tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline] BUG: KASAN: slab-out-of-bounds in do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654 Read of size 4 at addr ffff8880943cf188 by task syz-executor.2/17508 CPU: 0 PID: 17508 Comm: syz-executor.2 Not tainted 5.3.0-rc7+ #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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:618 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline] do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654 tcp_getsockopt+0xbf/0xe0 net/ipv4/tcp.c:3680 sock_common_getsockopt+0x94/0xd0 net/core/sock.c:3098 __sys_getsockopt+0x16d/0x310 net/socket.c:2129 __do_sys_getsockopt net/socket.c:2144 [inline] __se_sys_getsockopt net/socket.c:2141 [inline] __x64_sys_getsockopt+0xbe/0x150 net/socket.c:2141 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 Fixes: d8e18a516f8f ("net: Use skb accessors in network core") Signed-off-by: Eric Dumazet Acked-by: Soheil Hassas Yeganeh Cc: Matthew Wilcox (Oracle) Reported-by: syzbot Signed-off-by: David S. Miller

udp: only do GSO if # of segs > 1

2019-10-03T15:47:10Z

Prior to this change an application sending <= 1MSS worth of data and enabling UDP GSO would fail if the system had SW GSO enabled, but the same send would succeed if HW GSO offload is enabled. In addition to this inconsistency the error in the SW GSO case does not get back to the application if sending out of a real device so the user is unaware of this failure. With this change we only perform GSO if the # of segments is > 1 even if the application has enabled segmentation. I've also updated the relevant udpgso selftests. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Josh Hunt Reviewed-by: Willem de Bruijn Reviewed-by: Alexander Duyck Signed-off-by: David S. Miller

udp: fix gso_segs calculations

2019-10-03T15:47:10Z

Commit dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") added gso_segs calculation, but incorrectly got sizeof() the pointer and not the underlying data type. In addition let's fix the v6 case. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Fixes: dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") Signed-off-by: Josh Hunt Reviewed-by: Alexander Duyck Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

ipv6: drop incoming packets having a v4mapped source address

2019-10-03T15:40:21Z

This began with a syzbot report. syzkaller was injecting IPv6 TCP SYN packets having a v4mapped source address. After an unsuccessful 4-tuple lookup, TCP creates a request socket (SYN_RECV) and calls reqsk_queue_hash_req() reqsk_queue_hash_req() calls sk_ehashfn(sk) At this point we have AF_INET6 sockets, and the heuristic used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr) For the particular spoofed packet, we end up hashing V4 addresses which were not initialized by the TCP IPv6 stack, so KMSAN fired a warning. I first fixed sk_ehashfn() to test both source and destination addresses, but then faced various problems, including user-space programs like packetdrill that had similar assumptions. Instead of trying to fix the whole ecosystem, it is better to admit that we have a dual stack behavior, and that we can not build linux kernels without V4 stack anyway. The dual stack API automatically forces the traffic to be IPv4 if v4mapped addresses are used at bind() or connect(), so it makes no sense to allow IPv6 traffic to use the same v4mapped class. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Cc: Florian Westphal Cc: Hannes Frederic Sowa Reported-by: syzbot Signed-off-by: David S. Miller