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path: root/drivers/net/tun.c
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2021-02-11net: fix dev_ifsioc_locked() race conditionCong Wang
dev_ifsioc_locked() is called with only RCU read lock, so when there is a parallel writer changing the mac address, it could get a partially updated mac address, as shown below: Thread 1 Thread 2 // eth_commit_mac_addr_change() memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); // dev_ifsioc_locked() memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,...); Close this race condition by guarding them with a RW semaphore, like netdev_get_name(). We can not use seqlock here as it does not allow blocking. The writers already take RTNL anyway, so this does not affect the slow path. To avoid bothering existing dev_set_mac_address() callers in drivers, introduce a new wrapper just for user-facing callers on ioctl and rtnetlink paths. Note, bonding also changes slave mac addresses but that requires a separate patch due to the complexity of bonding code. Fixes: 3710becf8a58 ("net: RCU locking for simple ioctl()") Reported-by: "Gong, Sishuai" <sishuai@purdue.edu> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-19net: tun: fix misspellings using codespell toolMenglong Dong
Some typos are found out by codespell tool: $ codespell -w -i 3 ./drivers/net/tun.c aovid ==> avoid Fix typos found by codespell. Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn> Link: https://lore.kernel.org/r/20210118111539.35886-1-dong.menglong@zte.com.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-08net, xdp: Introduce xdp_prepare_buff utility routineLorenzo Bianconi
Introduce xdp_prepare_buff utility routine to initialize per-descriptor xdp_buff fields (e.g. xdp_buff pointers). Rely on xdp_prepare_buff() in all XDP capable drivers. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Shay Agroskin <shayagr@amazon.com> Acked-by: Martin Habets <habetsm.xilinx@gmail.com> Acked-by: Camelia Groza <camelia.groza@nxp.com> Acked-by: Marcin Wojtas <mw@semihalf.com> Link: https://lore.kernel.org/bpf/45f46f12295972a97da8ca01990b3e71501e9d89.1608670965.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-08net, xdp: Introduce xdp_init_buff utility routineLorenzo Bianconi
Introduce xdp_init_buff utility routine to initialize xdp_buff fields const over NAPI iterations (e.g. frame_sz or rxq pointer). Rely on xdp_init_buff in all XDP capable drivers. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Shay Agroskin <shayagr@amazon.com> Acked-by: Martin Habets <habetsm.xilinx@gmail.com> Acked-by: Camelia Groza <camelia.groza@nxp.com> Acked-by: Marcin Wojtas <mw@semihalf.com> Link: https://lore.kernel.org/bpf/7f8329b6da1434dc2b05a77f2e800b29628a8913.1608670965.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-07tap/tun: add skb_zcopy_init() helper for initialization.Jonathan Lemon
Replace direct assignments with skb_zcopy_init() for zerocopy cases where a new skb is initialized, without changing the reference counts. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07net: group skb_shinfo zerocopy related bits together.Jonathan Lemon
In preparation for expanded zerocopy (TX and RX), move the zerocopy related bits out of tx_flags into their own flag word. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07skbuff: Add skb parameter to the ubuf zerocopy callbackJonathan Lemon
Add an optional skb parameter to the zerocopy callback parameter, which is passed down from skb_zcopy_clear(). This gives access to the original skb, which is needed for upcoming RX zero-copy error handling. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-28tun: fix return value when the number of iovs exceeds MAX_SKB_FRAGSYunjian Wang
Currently the tun_napi_alloc_frags() function returns -ENOMEM when the number of iovs exceeds MAX_SKB_FRAGS + 1. However this is inappropriate, we should use -EMSGSIZE instead of -ENOMEM. The following distinctions are matters: 1. the caller need to drop the bad packet when -EMSGSIZE is returned, which means meeting a persistent failure. 2. the caller can try again when -ENOMEM is returned, which means meeting a transient failure. Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/1608864736-24332-1-git-send-email-wangyunjian@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-04Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Alexei Starovoitov says: ==================== pull-request: bpf-next 2020-12-03 The main changes are: 1) Support BTF in kernel modules, from Andrii. 2) Introduce preferred busy-polling, from Björn. 3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh. 4) Memcg-based memory accounting for bpf objects, from Roman. 5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits) selftests/bpf: Fix invalid use of strncat in test_sockmap libbpf: Use memcpy instead of strncpy to please GCC selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module selftests/bpf: Add tp_btf CO-RE reloc test for modules libbpf: Support attachment of BPF tracing programs to kernel modules libbpf: Factor out low-level BPF program loading helper bpf: Allow to specify kernel module BTFs when attaching BPF programs bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF selftests/bpf: Add support for marking sub-tests as skipped selftests/bpf: Add bpf_testmod kernel module for testing libbpf: Add kernel module BTF support for CO-RE relocations libbpf: Refactor CO-RE relocs to not assume a single BTF object libbpf: Add internal helper to load BTF data by FD bpf: Keep module's btf_data_size intact after load bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address() selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP bpf: Adds support for setting window clamp samples/bpf: Fix spelling mistake "recieving" -> "receiving" bpf: Fix cold build of test_progs-no_alu32 ... ==================== Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01xsk: Propagate napi_id to XDP socket Rx pathBjörn Töpel
Add napi_id to the xdp_rxq_info structure, and make sure the XDP socket pick up the napi_id in the Rx path. The napi_id is used to find the corresponding NAPI structure for socket busy polling. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Link: https://lore.kernel.org/bpf/20201130185205.196029-7-bjorn.topel@gmail.com
2020-11-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Trivial conflict in CAN, keep the net-next + the byteswap wrapper. Conflicts: drivers/net/can/usb/gs_usb.c Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-23net/tun: Call type change netdev notifiersMartin Schiller
Call netdev notifiers before and after changing the device type. Signed-off-by: Martin Schiller <ms@dev.tdt.de> Link: https://lore.kernel.org/r/20201118063919.29485-1-ms@dev.tdt.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-21tun: honor IOCB_NOWAIT flagJens Axboe
tun only checks the file O_NONBLOCK flag, but it should also be checking the iocb IOCB_NOWAIT flag. Any fops using ->read/write_iter() should check both, otherwise it breaks users that correctly expect O_NONBLOCK semantics if IOCB_NOWAIT is set. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/e9451860-96cc-c7c7-47b8-fe42cadd5f4c@kernel.dk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09tun: switch to net core provided statistics countersHeiner Kallweit
Switch tun to the standard statistics pattern: - use netdev->stats for the less frequently accessed counters - use netdev->tstats for the frequently accessed per-cpu counters v3: - add atomic_long_t member rx_frame_errors for making counter updates atomic Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
We got slightly different patches removing a double word in a comment in net/ipv4/raw.c - picked the version from net. Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached values instead of VNIC login response buffer (following what commit 507ebe6444a4 ("ibmvnic: Fix use-after-free of VNIC login response buffer") did). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-19net-tun: Eliminate two tun/xdp related function calls from vhost-netMaciej Żenczykowski
This provides a minor performance boost by virtue of inlining instead of cross module function calls. Test: builds Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200819010710.3959310-2-zenczykowski@gmail.com
2020-08-19net-tun: Add type safety to tun_xdp_to_ptr() and tun_ptr_to_xdp()Maciej Żenczykowski
This reduces likelihood of incorrect use. Test: builds Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200819010710.3959310-1-zenczykowski@gmail.com
2020-08-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-08-04 The following pull-request contains BPF updates for your *net-next* tree. We've added 73 non-merge commits during the last 9 day(s) which contain a total of 135 files changed, 4603 insertions(+), 1013 deletions(-). The main changes are: 1) Implement bpf_link support for XDP. Also add LINK_DETACH operation for the BPF syscall allowing processes with BPF link FD to force-detach, from Andrii Nakryiko. 2) Add BPF iterator for map elements and to iterate all BPF programs for efficient in-kernel inspection, from Yonghong Song and Alexei Starovoitov. 3) Separate bpf_get_{stack,stackid}() helpers for perf events in BPF to avoid unwinder errors, from Song Liu. 4) Allow cgroup local storage map to be shared between programs on the same cgroup. Also extend BPF selftests with coverage, from YiFei Zhu. 5) Add BPF exception tables to ARM64 JIT in order to be able to JIT BPF_PROBE_MEM load instructions, from Jean-Philippe Brucker. 6) Follow-up fixes on BPF socket lookup in combination with reuseport group handling. Also add related BPF selftests, from Jakub Sitnicki. 7) Allow to use socket storage in BPF_PROG_TYPE_CGROUP_SOCK-typed programs for socket create/release as well as bind functions, from Stanislav Fomichev. 8) Fix an info leak in xsk_getsockopt() when retrieving XDP stats via old struct xdp_statistics, from Peilin Ye. 9) Fix PT_REGS_RC{,_CORE}() macros in libbpf for MIPS arch, from Jerry Crunchtime. 10) Extend BPF kernel test infra with skb->family and skb->{local,remote}_ip{4,6} fields and allow user space to specify skb->dev via ifindex, from Dmitry Yakunin. 11) Fix a bpftool segfault due to missing program type name and make it more robust to prevent them in future gaps, from Quentin Monnet. 12) Consolidate cgroup helper functions across selftests and fix a v6 localhost resolver issue, from John Fastabend. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-31tun: add missing rcu annotation in tun_set_ebpf()Jason Wang
We expecte prog_p to be protected by rcu, so adding the rcu annotation to fix the following sparse warning: drivers/net/tun.c:3003:36: warning: incorrect type in argument 2 (different address spaces) drivers/net/tun.c:3003:36: expected struct tun_prog [noderef] __rcu **prog_p drivers/net/tun.c:3003:36: got struct tun_prog **prog_p drivers/net/tun.c:3292:42: warning: incorrect type in argument 2 (different address spaces) drivers/net/tun.c:3292:42: expected struct tun_prog **prog_p drivers/net/tun.c:3292:42: got struct tun_prog [noderef] __rcu ** drivers/net/tun.c:3296:42: warning: incorrect type in argument 2 (different address spaces) drivers/net/tun.c:3296:42: expected struct tun_prog **prog_p drivers/net/tun.c:3296:42: got struct tun_prog [noderef] __rcu ** Reported-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-25bpf, xdp: Remove XDP_QUERY_PROG and XDP_QUERY_PROG_HW XDP commandsAndrii Nakryiko
Now that BPF program/link management is centralized in generic net_device code, kernel code never queries program id from drivers, so XDP_QUERY_PROG/XDP_QUERY_PROG_HW commands are unnecessary. This patch removes all the implementations of those commands in kernel, along the xdp_attachment_query(). This patch was compile-tested on allyesconfig. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200722064603.3350758-10-andriin@fb.com
2020-06-30tun: implement header_ops->parse_protocol for AF_PACKETJason A. Donenfeld
The tun driver passes up skb->protocol to userspace in the form of PI headers. For AF_PACKET injection, we need to support its call chain of: packet_sendmsg -> packet_snd -> packet_parse_headers -> dev_parse_header_protocol -> parse_protocol Without a valid parse_protocol, this returns zero, and the tun driver then gives userspace bogus values that it can't deal with. Note that this isn't the case with tap, because tap already benefits from the shared infrastructure for ethernet headers. But with tun, there's nothing. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-01xdp: Rename convert_to_xdp_frame in xdp_convert_buff_to_frameLorenzo Bianconi
In order to use standard 'xdp' prefix, rename convert_to_xdp_frame utility routine in xdp_convert_buff_to_frame and replace all the occurrences Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/6344f739be0d1a08ab2b9607584c4d5478c8c083.1590698295.git.lorenzo@kernel.org
2020-06-01tun: correct header offsets in napi frags modeWillem de Bruijn
Tun in IFF_NAPI_FRAGS mode calls napi_gro_frags. Unlike netif_rx and netif_gro_receive, this expects skb->data to point to the mac layer. But skb_probe_transport_header, __skb_get_hash_symmetric, and xdp_do_generic in tun_get_user need skb->data to point to the network header. Flow dissection also needs skb->protocol set, so eth_type_trans has to be called. Ensure the link layer header lies in linear as eth_type_trans pulls ETH_HLEN. Then take the same code paths for frags as for not frags. Push the link layer header back just before calling napi_gro_frags. By pulling up to ETH_HLEN from frag0 into linear, this disables the frag0 optimization in the special case when IFF_NAPI_FRAGS is used with zero length iov[0] (and thus empty skb->linear). Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Petar Penkov <ppenkov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-14tun: Add XDP frame sizeJesper Dangaard Brouer
The tun driver have two code paths for running XDP (bpf_prog_run_xdp). In both cases 'buflen' contains enough tailroom for skb_shared_info. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/bpf/158945343419.97035.9594485183958037621.stgit@firesoul
2020-04-12net: tun: record RX queue in skb before do_xdp_generic()Gilberto Bertin
This allows netif_receive_generic_xdp() to correctly determine the RX queue from which the skb is coming, so that the context passed to the XDP program will contain the correct RX queue index. Signed-off-by: Gilberto Bertin <me@jibi.io> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-06tun: Don't put_page() for all negative return values from XDP programWill Deacon
When an XDP program is installed, tun_build_skb() grabs a reference to the current page fragment page if the program returns XDP_REDIRECT or XDP_TX. However, since tun_xdp_act() passes through negative return values from the XDP program, it is possible to trigger the error path by mistake and accidentally drop a reference to the fragments page without taking one, leading to a spurious free. This is believed to be the cause of some KASAN use-after-free reports from syzbot [1], although without a reproducer it is not possible to confirm whether this patch fixes the problem. Ensure that we only drop a reference to the fragments page if the XDP transmit or redirect operations actually fail. [1] https://syzkaller.appspot.com/bug?id=e76a6af1be4acd727ff6bbca669833f98cbf5d95 Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> CC: Eric Dumazet <edumazet@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Fixes: 8ae1aff0b331 ("tuntap: split out XDP logic") Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-06tun: reject unsupported coalescing paramsJakub Kicinski
Set ethtool_ops->supported_coalesce_params to let the core reject unsupported coalescing parameters. This driver did not previously reject unsupported parameters. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05tun: drop TUN_DEBUG and tun_debug()Michal Kubecek
TUN_DEBUG and tun_debug() are no longer used anywhere, drop them. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05tun: replace tun_debug() by netif_info()Michal Kubecek
The tun driver uses custom macro tun_debug() which is only available if TUN_DEBUG is set. Replace it by standard netif_ifinfo(). For that purpose, rename tun_struct::debug to msg_enable and make it u32 and always present. Finally, make tun_get_msglevel(), tun_set_msglevel() and TUNSETDEBUG ioctl independent of TUN_DEBUG. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05tun: drop useless debugging statementsMichal Kubecek
Some of the tun_debug() statements only inform us about entering a function which can be easily achieved with ftrace or kprobe. As tun_debug() is no-op unless TUN_DEBUG is set which requires editing the source and recompiling, setting up ftrace or kprobe is easier. Drop these debug statements. Also drop the tun_debug() statement informing about SIOCSIFHWADDR ioctl. We can monitor these through rtnetlink and it makes little sense to log address changes through ioctl but not changes through rtnetlink. Moreover, this tun_debug() is called even if the actual address change fails which makes it even less useful. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05tun: get rid of DBG1() macroMichal Kubecek
This macro is no-op unless TUN_DEBUG is defined (which requires editing and recompiling the source) and only does something if variable debug is 2 but that variable is zero initialized and never set to anything else. Moreover, the only use of the macro informs about entering function tun_chr_open() which can be easily achieved using ftrace or kprobe. Drop DBG1() macro, its only use and global variable debug. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05tun: fix misleading comment formatMichal Kubecek
The comment above tun_flow_save_rps_rxhash() starts with "/**" which makes it look like kerneldoc comment and results in warnings when building with W=1. Fix the format to make it look like a normal comment. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-23tun: Remove unnecessary BUG_ON check in tun_net_xmitDavid Ahern
The BUG_ON for NULL tfile is now redundant due to a recently added null check after the rcu_dereference. Remove the BUG_ON. Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Minor conflict in mlx5 because changes happened to code that has moved meanwhile. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-23tun: add mutex_unlock() call and napi.skb clearing in tun_get_user()Eric Dumazet
If both IFF_NAPI_FRAGS mode and XDP are enabled, and the XDP program consumes the skb, we need to clear the napi.skb (or risk a use-after-free) and release the mutex (or risk a deadlock) WARNING: lock held when returning to user space! 5.5.0-rc6-syzkaller #0 Not tainted ------------------------------------------------ syz-executor.0/455 is leaving the kernel with locks still held! 1 lock held by syz-executor.0/455: #0: ffff888098f6e748 (&tfile->napi_mutex){+.+.}, at: tun_get_user+0x1604/0x3fc0 drivers/net/tun.c:1835 Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Petar Penkov <ppenkov@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-16xdp: Use bulking for non-map XDP_REDIRECT and consolidate code pathsToke Høiland-Jørgensen
Since the bulk queue used by XDP_REDIRECT now lives in struct net_device, we can re-use the bulking for the non-map version of the bpf_redirect() helper. This is a simple matter of having xdp_do_redirect_slow() queue the frame on the bulk queue instead of sending it out with __bpf_tx_xdp(). Unfortunately we can't make the bpf_redirect() helper return an error if the ifindex doesn't exit (as bpf_redirect_map() does), because we don't have a reference to the network namespace of the ingress device at the time the helper is called. So we have to leave it as-is and keep the device lookup in xdp_do_redirect_slow(). Since this leaves less reason to have the non-map redirect code in a separate function, so we get rid of the xdp_do_redirect_slow() function entirely. This does lose us the tracepoint disambiguation, but fortunately the xdp_redirect and xdp_redirect_map tracepoints use the same tracepoint entry structures. This means both can contain a map index, so we can just amend the tracepoint definitions so we always emit the xdp_redirect(_err) tracepoints, but with the map ID only populated if a map is present. This means we retire the xdp_redirect_map(_err) tracepoints entirely, but keep the definitions around in case someone is still listening for them. With this change, the performance of the xdp_redirect sample program goes from 5Mpps to 8.4Mpps (a 68% increase). Since the flush functions are no longer map-specific, rename the flush() functions to drop _map from their names. One of the renamed functions is the xdp_do_flush_map() callback used in all the xdp-enabled drivers. To keep from having to update all drivers, use a #define to keep the old name working, and only update the virtual drivers in this patch. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/157918768505.1458396.17518057312953572912.stgit@toke.dk
2019-11-15tun: fix data-race in gro_normal_list()Petar Penkov
There is a race in the TUN driver between napi_busy_loop and napi_gro_frags. This commit resolves the race by adding the NAPI struct via netif_tx_napi_add, instead of netif_napi_add, which disables polling for the NAPI struct. KCSAN reported: BUG: KCSAN: data-race in gro_normal_list.part.0 / napi_busy_loop write to 0xffff8880b5d474b0 of 4 bytes by task 11205 on cpu 0: gro_normal_list.part.0+0x77/0xb0 net/core/dev.c:5682 gro_normal_list net/core/dev.c:5678 [inline] gro_normal_one net/core/dev.c:5692 [inline] napi_frags_finish net/core/dev.c:5705 [inline] napi_gro_frags+0x625/0x770 net/core/dev.c:5778 tun_get_user+0x2150/0x26a0 drivers/net/tun.c:1976 tun_chr_write_iter+0x79/0xd0 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x13b/0x3c0 fs/read_write.c:951 vfs_writev+0x118/0x1c0 fs/read_write.c:1015 do_writev+0xe3/0x250 fs/read_write.c:1058 __do_sys_writev fs/read_write.c:1131 [inline] __se_sys_writev fs/read_write.c:1128 [inline] __x64_sys_writev+0x4e/0x60 fs/read_write.c:1128 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880b5d474b0 of 4 bytes by task 11168 on cpu 1: gro_normal_list net/core/dev.c:5678 [inline] napi_busy_loop+0xda/0x4f0 net/core/dev.c:6126 sk_busy_loop include/net/busy_poll.h:108 [inline] __skb_recv_udp+0x4ad/0x560 net/ipv4/udp.c:1689 udpv6_recvmsg+0x29e/0xe90 net/ipv6/udp.c:288 inet6_recvmsg+0xbb/0x240 net/ipv6/af_inet6.c:592 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 sock_read_iter+0x15f/0x1e0 net/socket.c:967 call_read_iter include/linux/fs.h:1889 [inline] new_sync_read+0x389/0x4f0 fs/read_write.c:414 __vfs_read+0xb1/0xc0 fs/read_write.c:427 vfs_read fs/read_write.c:461 [inline] vfs_read+0x143/0x2c0 fs/read_write.c:446 ksys_read+0xd5/0x1b0 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read fs/read_write.c:595 [inline] __x64_sys_read+0x4c/0x60 fs/read_write.c:595 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 11168 Comm: syz-executor.0 Not tainted 5.4.0-rc6+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 943170998b20 ("tun: enable NAPI for TUN/TAP driver") Signed-off-by: Petar Penkov <ppenkov@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07tun: switch to u64_stats_tEric Dumazet
In order to fix this data-race found by KCSAN [1], switch to u64_stats_t helpers. They provide all the needed annotations, without adding extra cost. [1] BUG: KCSAN: data-race in tun_get_user / tun_net_get_stats64 read to 0xffffe8ffffd8aca8 of 8 bytes by task 4882 on cpu 0: tun_net_get_stats64+0x9b/0x230 drivers/net/tun.c:1171 dev_get_stats+0x89/0x1e0 net/core/dev.c:9103 rtnl_fill_stats+0x56/0x370 net/core/rtnetlink.c:1177 rtnl_fill_ifinfo+0xd3b/0x2100 net/core/rtnetlink.c:1667 rtmsg_ifinfo_build_skb+0xb0/0x150 net/core/rtnetlink.c:3472 rtmsg_ifinfo_event.part.0+0x4e/0xb0 net/core/rtnetlink.c:3504 rtmsg_ifinfo_event net/core/rtnetlink.c:3515 [inline] rtmsg_ifinfo+0x85/0x90 net/core/rtnetlink.c:3513 __dev_notify_flags+0x18b/0x200 net/core/dev.c:7649 dev_change_flags+0xb8/0xe0 net/core/dev.c:7691 dev_ifsioc+0x201/0x6a0 net/core/dev_ioctl.c:237 dev_ioctl+0x149/0x660 net/core/dev_ioctl.c:489 sock_do_ioctl+0xdb/0x230 net/socket.c:1061 sock_ioctl+0x3a3/0x5e0 net/socket.c:1189 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696 write to 0xffffe8ffffd8aca8 of 8 bytes by task 4883 on cpu 1: tun_get_user+0x1d94/0x2ba0 drivers/net/tun.c:2002 tun_chr_write_iter+0x79/0xd0 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write+0x388/0x4a0 fs/read_write.c:483 __vfs_write+0xb1/0xc0 fs/read_write.c:496 __kernel_write+0xb8/0x240 fs/read_write.c:515 write_pipe_buf+0xb6/0xf0 fs/splice.c:794 splice_from_pipe_feed fs/splice.c:500 [inline] __splice_from_pipe+0x248/0x480 fs/splice.c:624 splice_from_pipe+0xbb/0x100 fs/splice.c:659 default_file_splice_write+0x45/0x90 fs/splice.c:806 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1020 splice_direct_to_actor+0x215/0x510 fs/splice.c:975 do_splice_direct+0x161/0x1e0 fs/splice.c:1063 do_sendfile+0x384/0x7f0 fs/read_write.c:1464 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4883 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Several cases of overlapping changes which were for the most part trivially resolvable. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-09tun: remove possible false sharing in tun_flow_update()Eric Dumazet
As mentioned in https://github.com/google/ktsan/wiki/READ_ONCE-and-WRITE_ONCE#it-may-improve-performance a C compiler can legally transform if (e->queue_index != queue_index) e->queue_index = queue_index; to : e->queue_index = queue_index; Note that the code using jiffies has no issue, since jiffies has volatile attribute. if (e->updated != jiffies) e->updated = jiffies; Fixes: 83b1bc122cab ("tun: align write-heavy flow entry members to a cache line") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Zhang Yu <zhangyu31@baidu.com> Cc: Wang Li <wangli39@baidu.com> Cc: Li RongQing <lirongqing@baidu.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08Revert "tun: call dev_get_valid_name() before register_netdevice()"Eric Dumazet
This reverts commit 0ad646c81b2182f7fa67ec0c8c825e0ee165696d. As noticed by Jakub, this is no longer needed after commit 11fc7d5a0a2d ("tun: fix memory leak in error path") This no longer exports dev_get_valid_name() for the exclusive use of tun driver. Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08tun: fix memory leak in error pathEric Dumazet
syzbot reported a warning [1] that triggered after recent Jiri patch. This exposes a bug that we hit already in the past (see commit ff244c6b29b1 ("tun: handle register_netdevice() failures properly") for details) tun uses priv->destructor without an ndo_init() method. register_netdevice() can return an error, but will not call priv->destructor() in some cases. Jiri recent patch added one more. A long term fix would be to transfer the initialization of what we destroy in ->destructor() in the ndo_init() This looks a bit risky given the complexity of tun driver. A simpler fix is to detect after the failed register_netdevice() if the tun_free_netdev() function was called already. [1] ODEBUG: free active (active state 0) object type: timer_list hint: tun_flow_cleanup+0x0/0x280 drivers/net/tun.c:457 WARNING: CPU: 0 PID: 8653 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 lib/debugobjects.c:481 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 8653 Comm: syz-executor976 Not tainted 5.4.0-rc1-next-20191004 #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 panic+0x2dc/0x755 kernel/panic.c:220 __warn.cold+0x2f/0x3c kernel/panic.c:581 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028 RIP: 0010:debug_print_object+0x168/0x250 lib/debugobjects.c:481 Code: dd 80 b9 e6 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd 80 b9 e6 87 48 c7 c7 e0 ae e6 87 e8 80 84 ff fd <0f> 0b 83 05 e3 ee 80 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3 RSP: 0018:ffff888095997a28 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815cb526 RDI: ffffed1012b32f37 RBP: ffff888095997a68 R08: ffff8880a92ac580 R09: ffffed1015d04101 R10: ffffed1015d04100 R11: ffff8880ae820807 R12: 0000000000000001 R13: ffffffff88fb5340 R14: ffffffff81627110 R15: ffff8880aa41eab8 __debug_check_no_obj_freed lib/debugobjects.c:963 [inline] debug_check_no_obj_freed+0x2d4/0x43f lib/debugobjects.c:994 kfree+0xf8/0x2c0 mm/slab.c:3755 kvfree+0x61/0x70 mm/util.c:593 netdev_freemem net/core/dev.c:9384 [inline] free_netdev+0x39d/0x450 net/core/dev.c:9533 tun_set_iff drivers/net/tun.c:2871 [inline] __tun_chr_ioctl+0x317b/0x3f30 drivers/net/tun.c:3075 tun_chr_ioctl+0x2b/0x40 drivers/net/tun.c:3355 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:539 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:726 ksys_ioctl+0xab/0xd0 fs/ioctl.c:743 __do_sys_ioctl fs/ioctl.c:750 [inline] __se_sys_ioctl fs/ioctl.c:748 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:748 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441439 Code: e8 9c ae 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0f 83 3b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff61c37438 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441439 RDX: 0000000020000400 RSI: 00000000400454ca RDI: 0000000000000004 RBP: 00007fff61c37470 R08: 0000000000000001 R09: 0000000100000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff R13: 0000000000000005 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: ff92741270bf ("net: introduce name_node struct to be used in hashlist") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Pirko <jiri@mellanox.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-01netfilter: drop bridge nf reset from nf_resetFlorian Westphal
commit 174e23810cd31 ("sk_buff: drop all skb extensions on free and skb scrubbing") made napi recycle always drop skb extensions. The additional skb_ext_del() that is performed via nf_reset on napi skb recycle is not needed anymore. Most nf_reset() calls in the stack are there so queued skb won't block 'rmmod nf_conntrack' indefinitely. This removes the skb_ext_del from nf_reset, and renames it to a more fitting nf_reset_ct(). In a few selected places, add a call to skb_ext_reset to make sure that no active extensions remain. I am submitting this for "net", because we're still early in the release cycle. The patch applies to net-next too, but I think the rename causes needless divergence between those trees. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-09-12tun: fix use-after-free when register netdev failedYang Yingliang
I got a UAF repport in tun driver when doing fuzzy test: [ 466.269490] ================================================================== [ 466.271792] BUG: KASAN: use-after-free in tun_chr_read_iter+0x2ca/0x2d0 [ 466.271806] Read of size 8 at addr ffff888372139250 by task tun-test/2699 [ 466.271810] [ 466.271824] CPU: 1 PID: 2699 Comm: tun-test Not tainted 5.3.0-rc1-00001-g5a9433db2614-dirty #427 [ 466.271833] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 466.271838] Call Trace: [ 466.271858] dump_stack+0xca/0x13e [ 466.271871] ? tun_chr_read_iter+0x2ca/0x2d0 [ 466.271890] print_address_description+0x79/0x440 [ 466.271906] ? vprintk_func+0x5e/0xf0 [ 466.271920] ? tun_chr_read_iter+0x2ca/0x2d0 [ 466.271935] __kasan_report+0x15c/0x1df [ 466.271958] ? tun_chr_read_iter+0x2ca/0x2d0 [ 466.271976] kasan_report+0xe/0x20 [ 466.271987] tun_chr_read_iter+0x2ca/0x2d0 [ 466.272013] do_iter_readv_writev+0x4b7/0x740 [ 466.272032] ? default_llseek+0x2d0/0x2d0 [ 466.272072] do_iter_read+0x1c5/0x5e0 [ 466.272110] vfs_readv+0x108/0x180 [ 466.299007] ? compat_rw_copy_check_uvector+0x440/0x440 [ 466.299020] ? fsnotify+0x888/0xd50 [ 466.299040] ? __fsnotify_parent+0xd0/0x350 [ 466.299064] ? fsnotify_first_mark+0x1e0/0x1e0 [ 466.304548] ? vfs_write+0x264/0x510 [ 466.304569] ? ksys_write+0x101/0x210 [ 466.304591] ? do_preadv+0x116/0x1a0 [ 466.304609] do_preadv+0x116/0x1a0 [ 466.309829] do_syscall_64+0xc8/0x600 [ 466.309849] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 466.309861] RIP: 0033:0x4560f9 [ 466.309875] Code: 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 [ 466.309889] RSP: 002b:00007ffffa5166e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000127 [ 466.322992] RAX: ffffffffffffffda RBX: 0000000000400460 RCX: 00000000004560f9 [ 466.322999] RDX: 0000000000000003 RSI: 00000000200008c0 RDI: 0000000000000003 [ 466.323007] RBP: 00007ffffa516700 R08: 0000000000000004 R09: 0000000000000000 [ 466.323014] R10: 0000000000000000 R11: 0000000000000206 R12: 000000000040cb10 [ 466.323021] R13: 0000000000000000 R14: 00000000006d7018 R15: 0000000000000000 [ 466.323057] [ 466.323064] Allocated by task 2605: [ 466.335165] save_stack+0x19/0x80 [ 466.336240] __kasan_kmalloc.constprop.8+0xa0/0xd0 [ 466.337755] kmem_cache_alloc+0xe8/0x320 [ 466.339050] getname_flags+0xca/0x560 [ 466.340229] user_path_at_empty+0x2c/0x50 [ 466.341508] vfs_statx+0xe6/0x190 [ 466.342619] __do_sys_newstat+0x81/0x100 [ 466.343908] do_syscall_64+0xc8/0x600 [ 466.345303] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 466.347034] [ 466.347517] Freed by task 2605: [ 466.348471] save_stack+0x19/0x80 [ 466.349476] __kasan_slab_free+0x12e/0x180 [ 466.350726] kmem_cache_free+0xc8/0x430 [ 466.351874] putname+0xe2/0x120 [ 466.352921] filename_lookup+0x257/0x3e0 [ 466.354319] vfs_statx+0xe6/0x190 [ 466.355498] __do_sys_newstat+0x81/0x100 [ 466.356889] do_syscall_64+0xc8/0x600 [ 466.358037] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 466.359567] [ 466.360050] The buggy address belongs to the object at ffff888372139100 [ 466.360050] which belongs to the cache names_cache of size 4096 [ 466.363735] The buggy address is located 336 bytes inside of [ 466.363735] 4096-byte region [ffff888372139100, ffff88837213a100) [ 466.367179] The buggy address belongs to the page: [ 466.368604] page:ffffea000dc84e00 refcount:1 mapcount:0 mapping:ffff8883df1b4f00 index:0x0 compound_mapcount: 0 [ 466.371582] flags: 0x2fffff80010200(slab|head) [ 466.372910] raw: 002fffff80010200 dead000000000100 dead000000000122 ffff8883df1b4f00 [ 466.375209] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 [ 466.377778] page dumped because: kasan: bad access detected [ 466.379730] [ 466.380288] Memory state around the buggy address: [ 466.381844] ffff888372139100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 466.384009] ffff888372139180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 466.386131] >ffff888372139200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 466.388257] ^ [ 466.390234] ffff888372139280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 466.392512] ffff888372139300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 466.394667] ================================================================== tun_chr_read_iter() accessed the memory which freed by free_netdev() called by tun_set_iff(): CPUA CPUB tun_set_iff() alloc_netdev_mqs() tun_attach() tun_chr_read_iter() tun_get() tun_do_read() tun_ring_recv() register_netdevice() <-- inject error goto err_detach tun_detach_all() <-- set RCV_SHUTDOWN free_netdev() <-- called from err_free_dev path netdev_freemem() <-- free the memory without check refcount (In this path, the refcount cannot prevent freeing the memory of dev, and the memory will be used by dev_put() called by tun_chr_read_iter() on CPUB.) (Break from tun_ring_recv(), because RCV_SHUTDOWN is set) tun_put() dev_put() <-- use the memory freed by netdev_freemem() Put the publishing of tfile->tun after register_netdevice(), so tun_get() won't get the tun pointer that freed by err_detach path if register_netdevice() failed. Fixes: eb0fb363f920 ("tuntap: attach queue 0 before registering netdevice") Reported-by: Hulk Robot <hulkci@huawei.com> Suggested-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-25tun: mark small packets as owned by the tap sockAlexis Bauvin
- v1 -> v2: Move skb_set_owner_w to __tun_build_skb to reduce patch size Small packets going out of a tap device go through an optimized code path that uses build_skb() rather than sock_alloc_send_pskb(). The latter calls skb_set_owner_w(), but the small packet code path does not. The net effect is that small packets are not owned by the userland application's socket (e.g. QEMU), while large packets are. This can be seen with a TCP session, where packets are not owned when the window size is small enough (around PAGE_SIZE), while they are once the window grows (note that this requires the host to support virtio tso for the guest to offload segmentation). All this leads to inconsistent behaviour in the kernel, especially on netfilter modules that uses sk->socket (e.g. xt_owner). Fixes: 66ccbc9c87c2 ("tap: use build_skb() for small packet") Signed-off-by: Alexis Bauvin <abauvin@scaleway.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08coallocate socket_wq with socket itselfAl Viro
socket->wq is assign-once, set when we are initializing both struct socket it's in and struct socket_wq it points to. As the matter of fact, the only reason for separate allocation was the ability to RCU-delay freeing of socket_wq. RCU-delaying the freeing of socket itself gets rid of that need, so we can just fold struct socket_wq into the end of struct socket and simplify the life both for sock_alloc_inode() (one allocation instead of two) and for tun/tap oddballs, where we used to embed struct socket and struct socket_wq into the same structure (now - embedding just the struct socket). Note that reference to struct socket_wq in struct sock does remain a reference - that's unchanged. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-18tun: wake up waitqueues after IFF_UP is setFei Li
Currently after setting tap0 link up, the tun code wakes tx/rx waited queues up in tun_net_open() when .ndo_open() is called, however the IFF_UP flag has not been set yet. If there's already a wait queue, it would fail to transmit when checking the IFF_UP flag in tun_sendmsg(). Then the saving vhost_poll_start() will add the wq into wqh until it is waken up again. Although this works when IFF_UP flag has been set when tun_chr_poll detects; this is not true if IFF_UP flag has not been set at that time. Sadly the latter case is a fatal error, as the wq will never be waken up in future unless later manually setting link up on purpose. Fix this by moving the wakeup process into the NETDEV_UP event notifying process, this makes sure IFF_UP has been set before all waited queues been waken up. Signed-off-by: Fei Li <lifei.shirley@bytedance.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157Thomas Gleixner
Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-09tuntap: synchronize through tfiles array instead of tun->numqueuesJason Wang
When a queue(tfile) is detached through __tun_detach(), we move the last enabled tfile to the position where detached one sit but don't NULL out last position. We expect to synchronize the datapath through tun->numqueues. Unfortunately, this won't work since we're lacking sufficient mechanism to order or synchronize the access to tun->numqueues. To fix this, NULL out the last position during detaching and check RCU protected tfile against NULL instead of checking tun->numqueues in datapath. Cc: YueHaibing <yuehaibing@huawei.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: weiyongjun (A) <weiyongjun1@huawei.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Fixes: c8d68e6be1c3b ("tuntap: multiqueue support") Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>