kernel/net/ipv6/ipv6_sockglue.c, branch linux-6.2.y

inet6: Clean up failure path in do_ipv6_setsockopt().

2022-10-24T08:40:39Z

We can reuse the unlock label above and need not repeat the same code. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller

tcp: Fix data races around icsk->icsk_af_ops.

2022-10-13T00:50:37Z

setsockopt(IPV6_ADDRFORM) and tcp_v6_connect() change icsk->icsk_af_ops under lock_sock(), but tcp_(get|set)sockopt() read it locklessly. To avoid load/store tearing, we need to add READ_ONCE() and WRITE_ONCE() for the reads and writes. Thanks to Eric Dumazet for providing the syzbot report: BUG: KCSAN: data-race in tcp_setsockopt / tcp_v6_connect write to 0xffff88813c624518 of 8 bytes by task 23936 on cpu 0: tcp_v6_connect+0x5b3/0xce0 net/ipv6/tcp_ipv6.c:240 __inet_stream_connect+0x159/0x6d0 net/ipv4/af_inet.c:660 inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724 __sys_connect_file net/socket.c:1976 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:2000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88813c624518 of 8 bytes by task 23937 on cpu 1: tcp_setsockopt+0x147/0x1c80 net/ipv4/tcp.c:3789 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3585 __sys_setsockopt+0x212/0x2b0 net/socket.c:2252 __do_sys_setsockopt net/socket.c:2263 [inline] __se_sys_setsockopt net/socket.c:2260 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffffffff8539af68 -> 0xffffffff8539aff8 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 23937 Comm: syz-executor.5 Not tainted 6.0.0-rc4-syzkaller-00331-g4ed9c1e971b1-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot Reported-by: Eric Dumazet Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski

ipv6: Fix data races around sk->sk_prot.

2022-10-13T00:50:37Z

Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot") fixed some data-races around sk->sk_prot but it was not enough. Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid load tearing. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski

udp: Call inet6_destroy_sock() in setsockopt(IPV6_ADDRFORM).

2022-10-13T00:50:37Z

Commit 4b340ae20d0e ("IPv6: Complete IPV6_DONTFRAG support") forgot to add a change to free inet6_sk(sk)->rxpmtu while converting an IPv6 socket into IPv4 with IPV6_ADDRFORM. After conversion, sk_prot is changed to udp_prot and ->destroy() never cleans it up, resulting in a memory leak. This is due to the discrepancy between inet6_destroy_sock() and IPV6_ADDRFORM, so let's call inet6_destroy_sock() from IPV6_ADDRFORM to remove the difference. However, this is not enough for now because rxpmtu can be changed without lock_sock() after commit 03485f2adcde ("udpv6: Add lockless sendmsg() support"). We will fix this case in the following patch. Note we will rename inet6_destroy_sock() to inet6_cleanup_sock() and remove unnecessary inet6_destroy_sock() calls in sk_prot->destroy() in the future. Fixes: 4b340ae20d0e ("IPv6: Complete IPV6_DONTFRAG support") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski

tcp/udp: Fix memory leak in ipv6_renew_options().

2022-10-13T00:50:37Z

syzbot reported a memory leak [0] related to IPV6_ADDRFORM. The scenario is that while one thread is converting an IPv6 socket into IPv4 with IPV6_ADDRFORM, another thread calls do_ipv6_setsockopt() and allocates memory to inet6_sk(sk)->XXX after conversion. Then, the converted sk with (tcp|udp)_prot never frees the IPv6 resources, which inet6_destroy_sock() should have cleaned up. setsockopt(IPV6_ADDRFORM) setsockopt(IPV6_DSTOPTS) +-----------------------+ +----------------------+ - do_ipv6_setsockopt(sk, ...) - sockopt_lock_sock(sk) - do_ipv6_setsockopt(sk, ...) - lock_sock(sk) ^._ called via tcpv6_prot - WRITE_ONCE(sk->sk_prot, &tcp_prot) before WRITE_ONCE() - xchg(&np->opt, NULL) - txopt_put(opt) - sockopt_release_sock(sk) - release_sock(sk) - sockopt_lock_sock(sk) - lock_sock(sk) - ipv6_set_opt_hdr(sk, ...) - ipv6_update_options(sk, opt) - xchg(&inet6_sk(sk)->opt, opt) ^._ opt is never freed. - sockopt_release_sock(sk) - release_sock(sk) Since IPV6_DSTOPTS allocates options under lock_sock(), we can avoid this memory leak by testing whether sk_family is changed by IPV6_ADDRFORM after acquiring the lock. This issue exists from the initial commit between IPV6_ADDRFORM and IPV6_PKTOPTIONS. [0]: BUG: memory leak unreferenced object 0xffff888009ab9f80 (size 96): comm "syz-executor583", pid 328, jiffies 4294916198 (age 13.034s) hex dump (first 32 bytes): 01 00 00 00 48 00 00 00 08 00 00 00 00 00 00 00 ....H........... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000002ee98ae1>] kmalloc include/linux/slab.h:605 [inline] [<000000002ee98ae1>] sock_kmalloc+0xb3/0x100 net/core/sock.c:2566 [<0000000065d7b698>] ipv6_renew_options+0x21e/0x10b0 net/ipv6/exthdrs.c:1318 [<00000000a8c756d7>] ipv6_set_opt_hdr net/ipv6/ipv6_sockglue.c:354 [inline] [<00000000a8c756d7>] do_ipv6_setsockopt.constprop.0+0x28b7/0x4350 net/ipv6/ipv6_sockglue.c:668 [<000000002854d204>] ipv6_setsockopt+0xdf/0x190 net/ipv6/ipv6_sockglue.c:1021 [<00000000e69fdcf8>] tcp_setsockopt+0x13b/0x2620 net/ipv4/tcp.c:3789 [<0000000090da4b9b>] __sys_setsockopt+0x239/0x620 net/socket.c:2252 [<00000000b10d192f>] __do_sys_setsockopt net/socket.c:2263 [inline] [<00000000b10d192f>] __se_sys_setsockopt net/socket.c:2260 [inline] [<00000000b10d192f>] __x64_sys_setsockopt+0xbe/0x160 net/socket.c:2260 [<000000000a80d7aa>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<000000000a80d7aa>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 [<000000004562b5c6>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2022-09-06T21:21:18Z

Daniel Borkmann says: ==================== pull-request: bpf-next 2022-09-05 The following pull-request contains BPF updates for your *net-next* tree. We've added 106 non-merge commits during the last 18 day(s) which contain a total of 159 files changed, 5225 insertions(+), 1358 deletions(-). There are two small merge conflicts, resolve them as follows: 1) tools/testing/selftests/bpf/DENYLIST.s390x Commit 27e23836ce22 ("selftests/bpf: Add lru_bug to s390x deny list") in bpf tree was needed to get BPF CI green on s390x, but it conflicted with newly added tests on bpf-next. Resolve by adding both hunks, result: [...] lru_bug # prog 'printk': failed to auto-attach: -524 setget_sockopt # attach unexpected error: -524 (trampoline) cb_refs # expected error message unexpected error: -524 (trampoline) cgroup_hierarchical_stats # JIT does not support calling kernel function (kfunc) htab_update # failed to attach: ERROR: strerror_r(-524)=22 (trampoline) [...] 2) net/core/filter.c Commit 1227c1771dd2 ("net: Fix data-races around sysctl_[rw]mem_(max|default).") from net tree conflicts with commit 29003875bd5b ("bpf: Change bpf_setsockopt(SOL_SOCKET) to reuse sk_setsockopt()") from bpf-next tree. Take the code as it is from bpf-next tree, result: [...] if (getopt) { if (optname == SO_BINDTODEVICE) return -EINVAL; return sk_getsockopt(sk, SOL_SOCKET, optname, KERNEL_SOCKPTR(optval), KERNEL_SOCKPTR(optlen)); } return sk_setsockopt(sk, SOL_SOCKET, optname, KERNEL_SOCKPTR(optval), *optlen); [...] The main changes are: 1) Add any-context BPF specific memory allocator which is useful in particular for BPF tracing with bonus of performance equal to full prealloc, from Alexei Starovoitov. 2) Big batch to remove duplicated code from bpf_{get,set}sockopt() helpers as an effort to reuse the existing core socket code as much as possible, from Martin KaFai Lau. 3) Extend BPF flow dissector for BPF programs to just augment the in-kernel dissector with custom logic. In other words, allow for partial replacement, from Shmulik Ladkani. 4) Add a new cgroup iterator to BPF with different traversal options, from Hao Luo. 5) Support for BPF to collect hierarchical cgroup statistics efficiently through BPF integration with the rstat framework, from Yosry Ahmed. 6) Support bpf_{g,s}et_retval() under more BPF cgroup hooks, from Stanislav Fomichev. 7) BPF hash table and local storages fixes under fully preemptible kernel, from Hou Tao. 8) Add various improvements to BPF selftests and libbpf for compilation with gcc BPF backend, from James Hilliard. 9) Fix verifier helper permissions and reference state management for synchronous callbacks, from Kumar Kartikeya Dwivedi. 10) Add support for BPF selftest's xskxceiver to also be used against real devices that support MAC loopback, from Maciej Fijalkowski. 11) Various fixes to the bpf-helpers(7) man page generation script, from Quentin Monnet. 12) Document BPF verifier's tnum_in(tnum_range(), ...) gotchas, from Shung-Hsi Yu. 13) Various minor misc improvements all over the place. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (106 commits) bpf: Optimize rcu_barrier usage between hash map and bpf_mem_alloc. bpf: Remove usage of kmem_cache from bpf_mem_cache. bpf: Remove prealloc-only restriction for sleepable bpf programs. bpf: Prepare bpf_mem_alloc to be used by sleepable bpf programs. bpf: Remove tracing program restriction on map types bpf: Convert percpu hash map to per-cpu bpf_mem_alloc. bpf: Add percpu allocation support to bpf_mem_alloc. bpf: Batch call_rcu callbacks instead of SLAB_TYPESAFE_BY_RCU. bpf: Adjust low/high watermarks in bpf_mem_cache bpf: Optimize call_rcu in non-preallocated hash map. bpf: Optimize element count in non-preallocated hash map. bpf: Relax the requirement to use preallocated hash maps in tracing progs. samples/bpf: Reduce syscall overhead in map_perf_test. selftests/bpf: Improve test coverage of test_maps bpf: Convert hash map to bpf_mem_alloc. bpf: Introduce any context BPF specific memory allocator. selftest/bpf: Add test for bpf_getsockopt() bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt() bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt() bpf: Change bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt() ... ==================== Link: https://lore.kernel.org/r/20220905161136.9150-1-daniel@iogearbox.net Signed-off-by: Paolo Abeni

bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt()

2022-09-03T03:34:32Z

This patch changes bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt(). It removes the duplicated code from bpf_getsockopt(SOL_IPV6). This also makes bpf_getsockopt(SOL_IPV6) supporting the same set of optnames as in bpf_setsockopt(SOL_IPV6). In particular, this adds IPV6_AUTOFLOWLABEL support to bpf_getsockopt(SOL_IPV6). ipv6 could be compiled as a module. Like how other code solved it with stubs in ipv6_stubs.h, this patch adds the do_ipv6_getsockopt to the ipv6_bpf_stub. Signed-off-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20220902002931.2896218-1-kafai@fb.com Signed-off-by: Alexei Starovoitov

bpf: net: Avoid do_ipv6_getsockopt() taking sk lock when called from bpf

2022-09-03T03:34:31Z

Similar to the earlier patch that changes sk_getsockopt() to use sockopt_{lock,release}_sock() such that it can avoid taking the lock when called from bpf. This patch also changes do_ipv6_getsockopt() to use sockopt_{lock,release}_sock() such that bpf_getsockopt(SOL_IPV6) can reuse do_ipv6_getsockopt(). Although bpf_getsockopt(SOL_IPV6) currently does not support optname that requires lock_sock(), using sockopt_{lock,release}_sock() consistently across *_getsockopt() will make future optname addition harder to miss the sockopt_{lock,release}_sock() usage. eg. when adding new optname that requires a lock and the new optname is needed in bpf_getsockopt() also. Signed-off-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20220902002859.2893064-1-kafai@fb.com Signed-off-by: Alexei Starovoitov

bpf: net: Change do_ipv6_getsockopt() to take the sockptr_t argument

2022-09-03T03:34:31Z

Similar to the earlier patch that changes sk_getsockopt() to take the sockptr_t argument . This patch also changes do_ipv6_getsockopt() to take the sockptr_t argument such that a latter patch can make bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt(). Note on the change in ip6_mc_msfget(). This function is to return an array of sockaddr_storage in optval. This function is shared between ipv6_get_msfilter() and compat_ipv6_get_msfilter(). However, the sockaddr_storage is stored at different offset of the optval because of the difference between group_filter and compat_group_filter. Thus, a new 'ss_offset' argument is added to ip6_mc_msfget(). Signed-off-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20220902002853.2892532-1-kafai@fb.com Signed-off-by: Alexei Starovoitov

net: Add a len argument to compat_ipv6_get_msfilter()

2022-09-03T03:34:31Z

Pass the len to the compat_ipv6_get_msfilter() instead of compat_ipv6_get_msfilter() getting it again from optlen. Its counter part ipv6_get_msfilter() is also taking the len from do_ipv6_getsockopt(). Signed-off-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20220902002846.2892091-1-kafai@fb.com Signed-off-by: Alexei Starovoitov