linux.git/net/xdp, branch v6.9

xsk: validate user input for XDP_{UMEM|COMPLETION}_FILL_RING

2024-04-06T05:47:22+00:00

syzbot reported an illegal copy in xsk_setsockopt() [1]

Make sure to validate setsockopt() @optlen parameter.

[1]

 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
 BUG: KASAN: slab-out-of-bounds in xsk_setsockopt+0x909/0xa40 net/xdp/xsk.c:1420
Read of size 4 at addr ffff888028c6cde3 by task syz-executor.0/7549

CPU: 0 PID: 7549 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
  copy_from_sockptr include/linux/sockptr.h:55 [inline]
  xsk_setsockopt+0x909/0xa40 net/xdp/xsk.c:1420
  do_sock_setsockopt+0x3af/0x720 net/socket.c:2311
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fb40587de69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb40665a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fb4059abf80 RCX: 00007fb40587de69
RDX: 0000000000000005 RSI: 000000000000011b RDI: 0000000000000006
RBP: 00007fb4058ca47a R08: 0000000000000002 R09: 0000000000000000
R10: 0000000020001980 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fb4059abf80 R15: 00007fff57ee4d08
 

Allocated by task 7549:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
  kasan_kmalloc include/linux/kasan.h:211 [inline]
  __do_kmalloc_node mm/slub.c:3966 [inline]
  __kmalloc+0x233/0x4a0 mm/slub.c:3979
  kmalloc include/linux/slab.h:632 [inline]
  __cgroup_bpf_run_filter_setsockopt+0xd2f/0x1040 kernel/bpf/cgroup.c:1869
  do_sock_setsockopt+0x6b4/0x720 net/socket.c:2293
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

The buggy address belongs to the object at ffff888028c6cde0
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 1 bytes to the right of
 allocated 2-byte region [ffff888028c6cde0, ffff888028c6cde2)

The buggy address belongs to the physical page:
page:ffffea0000a31b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888028c6c9c0 pfn:0x28c6c
anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888014c41280 0000000000000000 dead000000000001
raw: ffff888028c6c9c0 0000000080800057 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 6648, tgid 6644 (syz-executor.0), ts 133906047828, free_ts 133859922223
  set_page_owner include/linux/page_owner.h:31 [inline]
  post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
  prep_new_page mm/page_alloc.c:1540 [inline]
  get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
  __alloc_pages+0x256/0x680 mm/page_alloc.c:4569
  __alloc_pages_node include/linux/gfp.h:238 [inline]
  alloc_pages_node include/linux/gfp.h:261 [inline]
  alloc_slab_page+0x5f/0x160 mm/slub.c:2175
  allocate_slab mm/slub.c:2338 [inline]
  new_slab+0x84/0x2f0 mm/slub.c:2391
  ___slab_alloc+0xc73/0x1260 mm/slub.c:3525
  __slab_alloc mm/slub.c:3610 [inline]
  __slab_alloc_node mm/slub.c:3663 [inline]
  slab_alloc_node mm/slub.c:3835 [inline]
  __do_kmalloc_node mm/slub.c:3965 [inline]
  __kmalloc_node+0x2db/0x4e0 mm/slub.c:3973
  kmalloc_node include/linux/slab.h:648 [inline]
  __vmalloc_area_node mm/vmalloc.c:3197 [inline]
  __vmalloc_node_range+0x5f9/0x14a0 mm/vmalloc.c:3392
  __vmalloc_node mm/vmalloc.c:3457 [inline]
  vzalloc+0x79/0x90 mm/vmalloc.c:3530
  bpf_check+0x260/0x19010 kernel/bpf/verifier.c:21162
  bpf_prog_load+0x1667/0x20f0 kernel/bpf/syscall.c:2895
  __sys_bpf+0x4ee/0x810 kernel/bpf/syscall.c:5631
  __do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
page last free pid 6650 tgid 6647 stack trace:
  reset_page_owner include/linux/page_owner.h:24 [inline]
  free_pages_prepare mm/page_alloc.c:1140 [inline]
  free_unref_page_prepare+0x95d/0xa80 mm/page_alloc.c:2346
  free_unref_page_list+0x5a3/0x850 mm/page_alloc.c:2532
  release_pages+0x2117/0x2400 mm/swap.c:1042
  tlb_batch_pages_flush mm/mmu_gather.c:98 [inline]
  tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
  tlb_flush_mmu+0x34d/0x4e0 mm/mmu_gather.c:300
  tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:392
  exit_mmap+0x4b6/0xd40 mm/mmap.c:3300
  __mmput+0x115/0x3c0 kernel/fork.c:1345
  exit_mm+0x220/0x310 kernel/exit.c:569
  do_exit+0x99e/0x27e0 kernel/exit.c:865
  do_group_exit+0x207/0x2c0 kernel/exit.c:1027
  get_signal+0x176e/0x1850 kernel/signal.c:2907
  arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
  exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
  exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
  __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
  syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212
  do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Memory state around the buggy address:
 ffff888028c6cc80: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff888028c6cd00: fa fc fc fc fa fc fc fc 00 fc fc fc 06 fc fc fc
>ffff888028c6cd80: fa fc fc fc fa fc fc fc fa fc fc fc 02 fc fc fc
                                                       ^
 ffff888028c6ce00: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff888028c6ce80: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc

Fixes: 423f38329d26 ("xsk: add umem fill queue support and mmap")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Cc: "Björn Töpel" 
Cc: Magnus Karlsson 
Cc: Maciej Fijalkowski 
Cc: Jonathan Lemon 
Acked-by: Daniel Borkmann 
Link: https://lore.kernel.org/r/20240404202738.3634547-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2024-03-03T04:50:59+00:00

Daniel Borkmann says:

====================
pull-request: bpf-next 2024-02-29

We've added 119 non-merge commits during the last 32 day(s) which contain
a total of 150 files changed, 3589 insertions(+), 995 deletions(-).

The main changes are:

1) Extend the BPF verifier to enable static subprog calls in spin lock
   critical sections, from Kumar Kartikeya Dwivedi.

2) Fix confusing and incorrect inference of PTR_TO_CTX argument type
   in BPF global subprogs, from Andrii Nakryiko.

3) Larger batch of riscv BPF JIT improvements and enabling inlining
   of the bpf_kptr_xchg() for RV64, from Pu Lehui.

4) Allow skeleton users to change the values of the fields in struct_ops
   maps at runtime, from Kui-Feng Lee.

5) Extend the verifier's capabilities of tracking scalars when they
   are spilled to stack, especially when the spill or fill is narrowing,
   from Maxim Mikityanskiy & Eduard Zingerman.

6) Various BPF selftest improvements to fix errors under gcc BPF backend,
   from Jose E. Marchesi.

7) Avoid module loading failure when the module trying to register
   a struct_ops has its BTF section stripped, from Geliang Tang.

8) Annotate all kfuncs in .BTF_ids section which eventually allows
   for automatic kfunc prototype generation from bpftool, from Daniel Xu.

9) Several updates to the instruction-set.rst IETF standardization
   document, from Dave Thaler.

10) Shrink the size of struct bpf_map resp. bpf_array,
    from Alexei Starovoitov.

11) Initial small subset of BPF verifier prepwork for sleepable bpf_timer,
    from Benjamin Tissoires.

12) Fix bpftool to be more portable to musl libc by using POSIX's
    basename(), from Arnaldo Carvalho de Melo.

13) Add libbpf support to gcc in CORE macro definitions,
    from Cupertino Miranda.

14) Remove a duplicate type check in perf_event_bpf_event,
    from Florian Lehner.

15) Fix bpf_spin_{un,}lock BPF helpers to actually annotate them
    with notrace correctly, from Yonghong Song.

16) Replace the deprecated bpf_lpm_trie_key 0-length array with flexible
    array to fix build warnings, from Kees Cook.

17) Fix resolve_btfids cross-compilation to non host-native endianness,
    from Viktor Malik.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits)
  selftests/bpf: Test if shadow types work correctly.
  bpftool: Add an example for struct_ops map and shadow type.
  bpftool: Generated shadow variables for struct_ops maps.
  libbpf: Convert st_ops->data to shadow type.
  libbpf: Set btf_value_type_id of struct bpf_map for struct_ops.
  bpf: Replace bpf_lpm_trie_key 0-length array with flexible array
  bpf, arm64: use bpf_prog_pack for memory management
  arm64: patching: implement text_poke API
  bpf, arm64: support exceptions
  arm64: stacktrace: Implement arch_bpf_stack_walk() for the BPF JIT
  bpf: add is_async_callback_calling_insn() helper
  bpf: introduce in_sleepable() helper
  bpf: allow more maps in sleepable bpf programs
  selftests/bpf: Test case for lacking CFI stub functions.
  bpf: Check cfi_stubs before registering a struct_ops type.
  bpf: Clarify batch lookup/lookup_and_delete semantics
  bpf, docs: specify which BPF_ABS and BPF_IND fields were zero
  bpf, docs: Fix typos in instruction-set.rst
  selftests/bpf: update tcp_custom_syncookie to use scalar packet offset
  bpf: Shrink size of struct bpf_map/bpf_array.
  ...
====================

Link: https://lore.kernel.org/r/20240301001625.8800-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

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

2024-02-22T23:29:26+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

net/ipv4/udp.c
  f796feabb9f5 ("udp: add local "peek offset enabled" flag")
  56667da7399e ("net: implement lockless setsockopt(SO_PEEK_OFF)")

Adjacent changes:

net/unix/garbage.c
  aa82ac51d633 ("af_unix: Drop oob_skb ref before purging queue in GC.")
  11498715f266 ("af_unix: Remove io_uring code for GC.")

Signed-off-by: Jakub Kicinski

xsk: Add truesize to skb_add_rx_frag().

2024-02-13T22:10:29+00:00

xsk_build_skb() allocates a page and adds it to the skb via
skb_add_rx_frag() and specifies 0 for truesize. This leads to a warning
in skb_add_rx_frag() with CONFIG_DEBUG_NET enabled because size is
larger than truesize.

Increasing truesize requires to add the same amount to socket's
sk_wmem_alloc counter in order not to underflow the counter during
release in the destructor (sock_wfree()).

Pass the size of the allocated page as truesize to skb_add_rx_frag().
Add this mount to socket's sk_wmem_alloc counter.

Fixes: cf24f5a5feea ("xsk: add support for AF_XDP multi-buffer on Tx path")
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Daniel Borkmann 
Acked-by: Maciej Fijalkowski 
Link: https://lore.kernel.org/bpf/20240202163221.2488589-1-bigeasy@linutronix.de

xsk: support redirect to any socket bound to the same umem

2024-02-06T04:01:15+00:00

Add support for directing a packet to any socket bound to the same
umem. This makes it possible to use the XDP program to select what
socket the packet should be received on. The user can populate the
XSKMAP with various sockets and as long as they share the same umem,
the XDP program can pick any one of them.

Suggested-by: Yuval El-Hanany 
Signed-off-by: Magnus Karlsson 
Reviewed-by: Willem de Bruijn 
Link: https://lore.kernel.org/r/20240205123553.22180-2-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov

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

2024-01-25T22:20:08+00:00

Cross-merge networking fixes after downstream PR.

No conflicts or adjacent changes.

Signed-off-by: Jakub Kicinski

xsk: make xsk_buff_pool responsible for clearing xdp_buff::flags

2024-01-25T00:24:06+00:00

XDP multi-buffer support introduced XDP_FLAGS_HAS_FRAGS flag that is
used by drivers to notify data path whether xdp_buff contains fragments
or not. Data path looks up mentioned flag on first buffer that occupies
the linear part of xdp_buff, so drivers only modify it there. This is
sufficient for SKB and XDP_DRV modes as usually xdp_buff is allocated on
stack or it resides within struct representing driver's queue and
fragments are carried via skb_frag_t structs. IOW, we are dealing with
only one xdp_buff.

ZC mode though relies on list of xdp_buff structs that is carried via
xsk_buff_pool::xskb_list, so ZC data path has to make sure that
fragments do *not* have XDP_FLAGS_HAS_FRAGS set. Otherwise,
xsk_buff_free() could misbehave if it would be executed against xdp_buff
that carries a frag with XDP_FLAGS_HAS_FRAGS flag set. Such scenario can
take place when within supplied XDP program bpf_xdp_adjust_tail() is
used with negative offset that would in turn release the tail fragment
from multi-buffer frame.

Calling xsk_buff_free() on tail fragment with XDP_FLAGS_HAS_FRAGS would
result in releasing all the nodes from xskb_list that were produced by
driver before XDP program execution, which is not what is intended -
only tail fragment should be deleted from xskb_list and then it should
be put onto xsk_buff_pool::free_list. Such multi-buffer frame will never
make it up to user space, so from AF_XDP application POV there would be
no traffic running, however due to free_list getting constantly new
nodes, driver will be able to feed HW Rx queue with recycled buffers.
Bottom line is that instead of traffic being redirected to user space,
it would be continuously dropped.

To fix this, let us clear the mentioned flag on xsk_buff_pool side
during xdp_buff initialization, which is what should have been done
right from the start of XSK multi-buffer support.

Fixes: 1bbc04de607b ("ice: xsk: add RX multi-buffer support")
Fixes: 1c9ba9c14658 ("i40e: xsk: add RX multi-buffer support")
Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX")
Signed-off-by: Maciej Fijalkowski 
Link: https://lore.kernel.org/r/20240124191602.566724-3-maciej.fijalkowski@intel.com
Signed-off-by: Alexei Starovoitov

xsk: recycle buffer in case Rx queue was full

2024-01-25T00:24:06+00:00

Add missing xsk_buff_free() call when __xsk_rcv_zc() failed to produce
descriptor to XSK Rx queue.

Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX")
Acked-by: Magnus Karlsson 
Signed-off-by: Maciej Fijalkowski 
Link: https://lore.kernel.org/r/20240124191602.566724-2-maciej.fijalkowski@intel.com
Signed-off-by: Alexei Starovoitov

sock_diag: add module pointer to "struct sock_diag_handler"

2024-01-23T14:13:54+00:00

Following patch is going to use RCU instead of
sock_diag_table_mutex acquisition.

This patch is a preparation, no change of behavior yet.

Signed-off-by: Eric Dumazet 
Reviewed-by: Guillaume Nault 
Reviewed-by: Kuniyuki Iwashima 
Reviewed-by: Willem de Bruijn 
Signed-off-by: Paolo Abeni

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2023-12-19T00:46:08+00:00

Alexei Starovoitov says:

====================
pull-request: bpf-next 2023-12-18

This PR is larger than usual and contains changes in various parts
of the kernel.

The main changes are:

1) Fix kCFI bugs in BPF, from Peter Zijlstra.

End result: all forms of indirect calls from BPF into kernel
and from kernel into BPF work with CFI enabled. This allows BPF
to work with CONFIG_FINEIBT=y.

2) Introduce BPF token object, from Andrii Nakryiko.

It adds an ability to delegate a subset of BPF features from privileged
daemon (e.g., systemd) through special mount options for userns-bound
BPF FS to a trusted unprivileged application. The design accommodates
suggestions from Christian Brauner and Paul Moore.

Example:
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
             -o delegate_cmds=prog_load:MAP_CREATE \
             -o delegate_progs=kprobe \
             -o delegate_attachs=xdp

3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei.

 - Complete precision tracking support for register spills
 - Fix verification of possibly-zero-sized stack accesses
 - Fix access to uninit stack slots
 - Track aligned STACK_ZERO cases as imprecise spilled registers.
   It improves the verifier "instructions processed" metric from single
   digit to 50-60% for some programs.
 - Fix verifier retval logic

4) Support for VLAN tag in XDP hints, from Larysa Zaremba.

5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu.

End result: better memory utilization and lower I$ miss for calls to BPF
via BPF trampoline.

6) Fix race between BPF prog accessing inner map and parallel delete,
from Hou Tao.

7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu.

It allows BPF interact with IPSEC infra. The intent is to support
software RSS (via XDP) for the upcoming ipsec pcpu work.
Experiments on AWS demonstrate single tunnel pcpu ipsec reaching
line rate on 100G ENA nics.

8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao.

9) BPF file verification via fsverity, from Song Liu.

It allows BPF progs get fsverity digest.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits)
  bpf: Ensure precise is reset to false in __mark_reg_const_zero()
  selftests/bpf: Add more uprobe multi fail tests
  bpf: Fail uprobe multi link with negative offset
  selftests/bpf: Test the release of map btf
  s390/bpf: Fix indirect trampoline generation
  selftests/bpf: Temporarily disable dummy_struct_ops test on s390
  x86/cfi,bpf: Fix bpf_exception_cb() signature
  bpf: Fix dtor CFI
  cfi: Add CFI_NOSEAL()
  x86/cfi,bpf: Fix bpf_struct_ops CFI
  x86/cfi,bpf: Fix bpf_callback_t CFI
  x86/cfi,bpf: Fix BPF JIT call
  cfi: Flip headers
  selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment
  selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test
  selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment
  bpf: Limit the number of kprobes when attaching program to multiple kprobes
  bpf: Limit the number of uprobes when attaching program to multiple uprobes
  bpf: xdp: Register generic_kfunc_set with XDP programs
  selftests/bpf: utilize string values for delegate_xxx mount options
  ...
====================

Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski