kernel.git/net/xdp, branch linux-5.4.y

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

2024-06-16T11:28:52Z

commit 237f3cf13b20db183d3706d997eedc3c49eacd44 upstream. 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 [shung-hsi.yu: copy_from_sockptr() in the context was replaced with copy_from_usr() because commit a7b75c5a8c414 ("net: pass a sockptr_t into ->setsockopt") was not present] Signed-off-by: Shung-Hsi Yu Signed-off-by: Greg Kroah-Hartman

xsk: Honor SO_BINDTODEVICE on bind

2023-07-27T06:37:23Z

[ Upstream commit f7306acec9aae9893d15e745c8791124d42ab10a ] Initial creation of an AF_XDP socket requires CAP_NET_RAW capability. A privileged process might create the socket and pass it to a non-privileged process for later use. However, that process will be able to bind the socket to any network interface. Even though it will not be able to receive any traffic without modification of the BPF map, the situation is not ideal. Sockets already have a mechanism that can be used to restrict what interface they can be attached to. That is SO_BINDTODEVICE. To change the SO_BINDTODEVICE binding the process will need CAP_NET_RAW. Make xsk_bind() honor the SO_BINDTODEVICE in order to allow safer workflow when non-privileged process is using AF_XDP. The intended workflow is following: 1. First process creates a bare socket with socket(AF_XDP, ...). 2. First process loads the XSK program to the interface. 3. First process adds the socket fd to a BPF map. 4. First process ties socket fd to a particular interface using SO_BINDTODEVICE. 5. First process sends socket fd to a second process. 6. Second process allocates UMEM. 7. Second process binds socket to the interface with bind(...). 8. Second process sends/receives the traffic. All the steps above are possible today if the first process is privileged and the second one has sufficient RLIMIT_MEMLOCK and no capabilities. However, the second process will be able to bind the socket to any interface it wants on step 7 and send traffic from it. With the proposed change, the second process will be able to bind the socket only to a specific interface chosen by the first process at step 4. Fixes: 965a99098443 ("xsk: add support for bind for Rx") Signed-off-by: Ilya Maximets Signed-off-by: Daniel Borkmann Acked-by: Magnus Karlsson Acked-by: John Fastabend Acked-by: Jason Wang Link: https://lore.kernel.org/bpf/20230703175329.3259672-1-i.maximets@ovn.org Signed-off-by: Sasha Levin

Revert "xsk: Do not sleep in poll() when need_wakeup set"

2021-12-22T08:29:40Z

commit 0706a78f31c4217ca144f630063ec9561a21548d upstream. This reverts commit bd0687c18e635b63233dc87f38058cd728802ab4. This patch causes a Tx only workload to go to sleep even when it does not have to, leading to misserable performance in skb mode. It fixed one rare problem but created a much worse one, so this need to be reverted while I try to craft a proper solution to the original problem. Fixes: bd0687c18e63 ("xsk: Do not sleep in poll() when need_wakeup set") Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211217145646.26449-1-magnus.karlsson@gmail.com Signed-off-by: Greg Kroah-Hartman

xsk: Do not sleep in poll() when need_wakeup set

2021-12-22T08:29:39Z

commit bd0687c18e635b63233dc87f38058cd728802ab4 upstream. Do not sleep in poll() when the need_wakeup flag is set. When this flag is set, the application needs to explicitly wake up the driver with a syscall (poll, recvmsg, sendmsg, etc.) to guarantee that Rx and/or Tx processing will be processed promptly. But the current code in poll(), sleeps first then wakes up the driver. This means that no driver processing will occur (baring any interrupts) until the timeout has expired. Fix this by checking the need_wakeup flag first and if set, wake the driver and return to the application. Only if need_wakeup is not set should the process sleep if there is a timeout set in the poll() call. Fixes: 77cd0d7b3f25 ("xsk: add support for need_wakeup flag in AF_XDP rings") Reported-by: Keith Wiles Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Acked-by: Maciej Fijalkowski Link: https://lore.kernel.org/bpf/20211214102607.7677-1-magnus.karlsson@gmail.com Signed-off-by: Greg Kroah-Hartman

xsk: Simplify detection of empty and full rings

2021-05-22T09:38:27Z

[ Upstream commit 11cc2d21499cabe7e7964389634ed1de3ee91d33 ] In order to set the correct return flags for poll, the xsk code has to check if the Rx queue is empty and if the Tx queue is full. This code was unnecessarily large and complex as it used the functions that are used to update the local state from the global state (xskq_nb_free and xskq_nb_avail). Since we are not doing this nor updating any data dependent on this state, we can simplify the functions. Another benefit from this is that we can also simplify the xskq_nb_free and xskq_nb_avail functions in a later commit. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/1576759171-28550-3-git-send-email-magnus.karlsson@intel.com Signed-off-by: Sasha Levin

xsk: Replace datagram_poll by sock_poll_wait

2020-12-30T10:50:53Z

[ Upstream commit f5da54187e33dce9bea63170667dbb0ca8d98194 ] datagram_poll will judge the current socket status (EPOLLIN, EPOLLOUT) based on the traditional socket information (eg: sk_wmem_alloc), but this does not apply to xsk. So this patch uses sock_poll_wait instead of datagram_poll, and the mask is calculated by xsk_poll. Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support") Signed-off-by: Xuan Zhuo Signed-off-by: Daniel Borkmann Acked-by: Magnus Karlsson Link: https://lore.kernel.org/bpf/e82f4697438cd63edbf271ebe1918db8261b7c09.1606555939.git.xuanzhuo@linux.alibaba.com Signed-off-by: Sasha Levin

xsk: Fix xsk_poll()'s return type

2020-12-30T10:50:53Z

[ Upstream commit 5d946c5abbaf68083fa6a41824dd79e1f06286d8 ] xsk_poll() is defined as returning 'unsigned int' but the .poll method is declared as returning '__poll_t', a bitwise type. Fix this by using the proper return type and using the EPOLL constants instead of the POLL ones, as required for __poll_t. Signed-off-by: Luc Van Oostenryck Signed-off-by: Daniel Borkmann Acked-by: Björn Töpel Link: https://lore.kernel.org/bpf/20191120001042.30830-1-luc.vanoostenryck@gmail.com Signed-off-by: Sasha Levin

xdp: Fix xsk_generic_xmit errno

2020-06-24T15:50:44Z

[ Upstream commit aa2cad0600ed2ca6a0ab39948d4db1666b6c962b ] Propagate sock_alloc_send_skb error code, not set it to EAGAIN unconditionally, when fail to allocate skb, which might cause that user space unnecessary loops. Fixes: 35fcde7f8deb ("xsk: support for Tx") Signed-off-by: Li RongQing Signed-off-by: Daniel Borkmann Acked-by: Björn Töpel Link: https://lore.kernel.org/bpf/1591852266-24017-1-git-send-email-lirongqing@baidu.com Signed-off-by: Sasha Levin

xsk: Add overflow check for u64 division, stored into u32

2020-06-03T06:21:36Z

commit b16a87d0aef7a6be766f6618976dc5ff2c689291 upstream. The npgs member of struct xdp_umem is an u32 entity, and stores the number of pages the UMEM consumes. The calculation of npgs npgs = size / PAGE_SIZE can overflow. To avoid overflow scenarios, the division is now first stored in a u64, and the result is verified to fit into 32b. An alternative would be storing the npgs as a u64, however, this wastes memory and is an unrealisticly large packet area. Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt") Reported-by: "Minh Bùi Quang" Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann Acked-by: Jonathan Lemon Link: https://lore.kernel.org/bpf/CACtPs=GGvV-_Yj6rbpzTVnopgi5nhMoCcTkSkYrJHGQHJWFZMQ@mail.gmail.com/ Link: https://lore.kernel.org/bpf/20200525080400.13195-1-bjorn.topel@gmail.com Signed-off-by: Greg Kroah-Hartman

xsk: Add missing check on user supplied headroom size

2020-04-23T08:36:21Z

commit 99e3a236dd43d06c65af0a2ef9cb44306aef6e02 upstream. Add a check that the headroom cannot be larger than the available space in the chunk. In the current code, a malicious user can set the headroom to a value larger than the chunk size minus the fixed XDP headroom. That way packets with a length larger than the supported size in the umem could get accepted and result in an out-of-bounds write. Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt") Reported-by: Bui Quang Minh Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Link: https://bugzilla.kernel.org/show_bug.cgi?id=207225 Link: https://lore.kernel.org/bpf/1586849715-23490-1-git-send-email-magnus.karlsson@intel.com Signed-off-by: Greg Kroah-Hartman