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2021-08-04sock: allow reading and changing sk_userlocks with setsockoptPavel Tikhomirov
SOCK_SNDBUF_LOCK and SOCK_RCVBUF_LOCK flags disable automatic socket buffers adjustment done by kernel (see tcp_fixup_rcvbuf() and tcp_sndbuf_expand()). If we've just created a new socket this adjustment is enabled on it, but if one changes the socket buffer size by setsockopt(SO_{SND,RCV}BUF*) it becomes disabled. CRIU needs to call setsockopt(SO_{SND,RCV}BUF*) on each socket on restore as it first needs to increase buffer sizes for packet queues restore and second it needs to restore back original buffer sizes. So after CRIU restore all sockets become non-auto-adjustable, which can decrease network performance of restored applications significantly. CRIU need to be able to restore sockets with enabled/disabled adjustment to the same state it was before dump, so let's add special setsockopt for it. Let's also export SOCK_SNDBUF_LOCK and SOCK_RCVBUF_LOCK flags to uAPI so that using these interface one can reenable automatic socket buffer adjustment on their sockets. Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: make switchdev_bridge_port_{,unoffload} loosely coupled with the bridgeVladimir Oltean
With the introduction of explicit offloading API in switchdev in commit 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded"), we started having Ethernet switch drivers calling directly into a function exported by net/bridge/br_switchdev.c, which is a function exported by the bridge driver. This means that drivers that did not have an explicit dependency on the bridge before, like cpsw and am65-cpsw, now do - otherwise it is not possible to call a symbol exported by a driver that can be built as module unless you are a module too. There was an attempt to solve the dependency issue in the form of commit b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module"). Grygorii Strashko, however, says about it: | In my opinion, the problem is a bit bigger here than just fixing the | build :( | | In case, of ^cpsw the switchdev mode is kinda optional and in many | cases (especially for testing purposes, NFS) the multi-mac mode is | still preferable mode. | | There were no such tight dependency between switchdev drivers and | bridge core before and switchdev serviced as independent, notification | based layer between them, so ^cpsw still can be "Y" and bridge can be | "M". Now for mostly every kernel build configuration the CONFIG_BRIDGE | will need to be set as "Y", or we will have to update drivers to | support build with BRIDGE=n and maintain separate builds for | networking vs non-networking testing. But is this enough? Wouldn't | it cause 'chain reaction' required to add more and more "Y" options | (like CONFIG_VLAN_8021Q)? | | PS. Just to be sure we on the same page - ARM builds will be forced | (with this patch) to have CONFIG_TI_CPSW_SWITCHDEV=m and so all our | automation testing will just fail with omap2plus_defconfig. In the light of this, it would be desirable for some configurations to avoid dependencies between switchdev drivers and the bridge, and have the switchdev mode as completely optional within the driver. Arnd Bergmann also tried to write a patch which better expressed the build time dependency for Ethernet switch drivers where the switchdev support is optional, like cpsw/am65-cpsw, and this made the drivers follow the bridge (compile as module if the bridge is a module) only if the optional switchdev support in the driver was enabled in the first place: https://patchwork.kernel.org/project/netdevbpf/patch/20210802144813.1152762-1-arnd@kernel.org/ but this still did not solve the fact that cpsw and am65-cpsw now must be built as modules when the bridge is a module - it just expressed correctly that optional dependency. But the new behavior is an apparent regression from Grygorii's perspective. So to support the use case where the Ethernet driver is built-in, NET_SWITCHDEV (a bool option) is enabled, and the bridge is a module, we need a framework that can handle the possible absence of the bridge from the running system, i.e. runtime bloatware as opposed to build-time bloatware. Luckily we already have this framework, since switchdev has been using it extensively. Events from the bridge side are transmitted to the driver side using notifier chains - this was originally done so that unrelated drivers could snoop for events emitted by the bridge towards ports that are implemented by other drivers (think of a switch driver with LAG offload that listens for switchdev events on a bonding/team interface that it offloads). There are also events which are transmitted from the driver side to the bridge side, which again are modeled using notifiers. SWITCHDEV_FDB_ADD_TO_BRIDGE is an example of this, and deals with notifying the bridge that a MAC address has been dynamically learned. So there is a precedent we can use for modeling the new framework. The difference compared to SWITCHDEV_FDB_ADD_TO_BRIDGE is that the work that the bridge needs to do when a port becomes offloaded is blocking in its nature: replay VLANs, MDBs etc. The calling context is indeed blocking (we are under rtnl_mutex), but the existing switchdev notification chain that the bridge is subscribed to is only the atomic one. So we need to subscribe the bridge to the blocking switchdev notification chain too. This patch: - keeps the driver-side perception of the switchdev_bridge_port_{,un}offload unchanged - moves the implementation of switchdev_bridge_port_{,un}offload from the bridge module into the switchdev module. - makes everybody that is subscribed to the switchdev blocking notifier chain "hear" offload & unoffload events - makes the bridge driver subscribe and handle those events - moves the bridge driver's handling of those events into 2 new functions called br_switchdev_port_{,un}offload. These functions contain in fact the core of the logic that was previously in switchdev_bridge_port_{,un}offload, just that now we go through an extra indirection layer to reach them. Unlike all the other switchdev notification structures, the structure used to carry the bridge port information, struct switchdev_notifier_brport_info, does not contain a "bool handled". This is because in the current usage pattern, we always know that a switchdev bridge port offloading event will be handled by the bridge, because the switchdev_bridge_port_offload() call was initiated by a NETDEV_CHANGEUPPER event in the first place, where info->upper_dev is a bridge. So if the bridge wasn't loaded, then the CHANGEUPPER event couldn't have happened. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04Merge tag 'linux-can-next-for-5.15-20210804' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next Marc Kleine-Budde says: ==================== pull-request: can-next 2021-08-04 this is a pull request of 5 patches for net-next/master. The first patch is by me and fixes a typo in a comment in the CAN J1939 protocol. The next 2 patches are by Oleksij Rempel and update the CAN J1939 protocol to send RX status updates via the error queue mechanism. The next patch is by me and adds a missing variable initialization to the flexcan driver (the problem was introduced in the current net-next cycle). The last patch is by Aswath Govindraju and adds power-domains to the Bosch m_can DT binding documentation. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04can: j1939: extend UAPI to notify about RX statusOleksij Rempel
To be able to create applications with user friendly feedback, we need be able to provide receive status information. Typical ETP transfer may take seconds or even hours. To give user some clue or show a progress bar, the stack should push status updates. Same as for the TX information, the socket error queue will be used with following new signals: - J1939_EE_INFO_RX_RTS - received and accepted request to send signal. - J1939_EE_INFO_RX_DPO - received data package offset signal - J1939_EE_INFO_RX_ABORT - RX session was aborted Instead of completion signal, user will get data package. To activate this signals, application should set SOF_TIMESTAMPING_RX_SOFTWARE to the SO_TIMESTAMPING socket option. This will avoid unpredictable application behavior for the old software. Link: https://lore.kernel.org/r/20210707094854.30781-3-o.rempel@pengutronix.de Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-08-04net: add netif_set_real_num_queues() for device reconfigJakub Kicinski
netif_set_real_num_rx_queues() and netif_set_real_num_tx_queues() can fail which breaks drivers trying to implement reconfiguration in a way that can't leave the device half-broken. In other words those functions are incompatible with prepare/commit approach. Luckily setting real number of queues can fail only if the number is increased, meaning that if we order operations correctly we can guarantee ending up with either new config (success), or the old one (on error). Provide a helper implementing such logic so that drivers don't have to duplicate it. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04net: add extack arg for link opsRocco Yue
Pass extack arg to validate_linkmsg and validate_link_af callbacks. If a netlink attribute has a reject_message, use the extended ack mechanism to carry the message back to user space. Signed-off-by: Rocco Yue <rocco.yue@mediatek.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04af_unix: Add OOB supportRao Shoaib
This patch adds OOB support for AF_UNIX sockets. The semantics is same as TCP. The last byte of a message with the OOB flag is treated as the OOB byte. The byte is separated into a skb and a pointer to the skb is stored in unix_sock. The pointer is used to enforce OOB semantics. Signed-off-by: Rao Shoaib <rao.shoaib@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04bus: fsl-mc: extend fsl_mc_get_endpoint() to pass interface IDIoana Ciornei
In case of a switch DPAA2 object, the interface ID is also needed when querying for the object endpoint. Extend fsl_mc_get_endpoint() so that users can also pass the interface ID that are interested in. Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03wan: remove sbni/granch driverArnd Bergmann
The driver was merged in 1999 and has only ever seen treewide cleanups since then, with no indication whatsoever that anyone has actually had access to hardware for testing the patches. >From the information in the link below, it appears that the hardware is for some leased line system in Russia that has since been discontinued, and useless without any remote end to connect to. As the driver still feels like a Linux-2.2 era artifact today, it appears that the best way forward is to just delete it. Link: https://www.tms.ru/%D0%90%D0%B4%D0%B0%D0%BF%D1%82%D0%B5%D1%80_%D0%B4%D0%BB%D1%8F_%D0%B2%D1%8B%D0%B4%D0%B5%D0%BB%D0%B5%D0%BD%D0%BD%D1%8B%D1%85_%D0%BB%D0%B8%D0%BD%D0%B8%D0%B9_Granch_SBNI12-10 Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03move netdev_boot_setup into Space.cArnd Bergmann
This is now only used by a handful of old ISA drivers, and can be moved into the file they already all depend on. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03ax88796: export ax_NS8390_init() hookMichael Schmitz
The block I/O code for the new X-Surf 100 ax88796 driver needs ax_NS8390_init() for error fixup in its block_output function. Export this static function through the ax_NS8390_reinit() wrapper so we can lose the lib8380.c include in the X-Surf 100 driver. [arnd: add the declaration in the header to avoid a -Wmissing-prototypes warning] Fixes: 861928f4e60e826c ("net-next: New ax88796 platform driver for Amiga X-Surf 100 Zorro board (m68k)") Signed-off-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03m68k: remove legacy probingArnd Bergmann
There are six m68k specific drivers that use the legacy probe method in drivers/net/Space.c. However, all of these only support a single device, and they completely ignore the command line settings from netdev_boot_setup_check, so there is really no point at all. Aside from sun3_82586, these already have a module_init function that can be used for built-in mode as well, simply by removing the #ifdef. Note that the 82596 driver was previously used on ISA as well, but that got dropped long ago. Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03appletalk: ltpc: remove static probingArnd Bergmann
This driver never relies on the netdev_boot_setup_check() to get its configuration, so it can just as well do its own probing all the time. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03bonding: add new option lacp_activeHangbin Liu
Add an option lacp_active, which is similar with team's runner.active. This option specifies whether to send LACPDU frames periodically. If set on, the LACPDU frames are sent along with the configured lacp_rate setting. If set off, the LACPDU frames acts as "speak when spoken to". Note, the LACPDU state frames still will be sent when init or unbind port. v2: remove module parameter Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03skbuff: introduce skb_expand_head()Vasily Averin
Like skb_realloc_headroom(), new helper increases headroom of specified skb. Unlike skb_realloc_headroom(), it does not allocate a new skb if possible; copies skb->sk on new skb when as needed and frees original skb in case of failures. This helps to simplify ip[6]_finish_output2() and a few other similar cases. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02net/mlx5: Move TTC logic to fs_ttcMaor Gottlieb
Now that TTC logic is not dependent on mlx5e structs, move it to lib/fs_ttc.c so it could be used other part of the mlx5 driver. Signed-off-by: Maor Gottlieb <maorg@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Mark Bloch <mbloch@nvidia.com> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2021-08-02net/ipv4: Replace one-element array with flexible-array memberGustavo A. R. Silva
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. Use an anonymous union with a couple of anonymous structs in order to keep userspace unchanged: $ pahole -C ip_msfilter net/ipv4/ip_sockglue.o struct ip_msfilter { union { struct { __be32 imsf_multiaddr_aux; /* 0 4 */ __be32 imsf_interface_aux; /* 4 4 */ __u32 imsf_fmode_aux; /* 8 4 */ __u32 imsf_numsrc_aux; /* 12 4 */ __be32 imsf_slist[1]; /* 16 4 */ }; /* 0 20 */ struct { __be32 imsf_multiaddr; /* 0 4 */ __be32 imsf_interface; /* 4 4 */ __u32 imsf_fmode; /* 8 4 */ __u32 imsf_numsrc; /* 12 4 */ __be32 imsf_slist_flex[0]; /* 16 0 */ }; /* 0 16 */ }; /* 0 20 */ /* size: 20, cachelines: 1, members: 1 */ /* last cacheline: 20 bytes */ }; Also, refactor the code accordingly and make use of the struct_size() and flex_array_size() helpers. This helps with the ongoing efforts to globally enable -Warray-bounds and get us closer to being able to tighten the FORTIFY_SOURCE routines on memcpy(). [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/109 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()Vladimir Oltean
No tagging driver uses this. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02nfc: hci: pass callback data param as pointer in nci_request()Krzysztof Kozlowski
The nci_request() receives a callback function and unsigned long data argument "opt" which is passed to the callback. Almost all of the nci_request() callers pass pointer to a stack variable as data argument. Only few pass scalar value (e.g. u8). All such callbacks do not modify passed data argument and in previous commit they were made as const. However passing pointers via unsigned long removes the const annotation. The callback could simply cast unsigned long to a pointer to writeable memory. Use "const void *" as type of this "opt" argument to solve this and prevent modifying the pointed contents. This is also consistent with generic pattern of passing data arguments - via "void *". In few places which pass scalar values, use casts via "unsigned long" to suppress any warnings. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-02net_sched: refactor TC action init APICong Wang
TC action ->init() API has 10 parameters, it becomes harder to read. Some of them are just boolean and can be replaced by flags. Similarly for the internal API tcf_action_init() and tcf_exts_validate(). This patch converts them to flags and fold them into the upper 16 bits of "flags", whose lower 16 bits are still reserved for user-space. More specifically, the following kernel flags are introduced: TCA_ACT_FLAGS_POLICE replace 'name' in a few contexts, to distinguish whether it is compatible with policer. TCA_ACT_FLAGS_BIND replaces 'bind', to indicate whether this action is bound to a filter. TCA_ACT_FLAGS_REPLACE replaces 'ovr' in most contexts, means we are replacing an existing action. TCA_ACT_FLAGS_NO_RTNL replaces 'rtnl_held' but has the opposite meaning, because we still hold RTNL in most cases. The only user-space flag TCA_ACT_FLAGS_NO_PERCPU_STATS is untouched and still stored as before. I have tested this patch with tdc and I do not see any failure related to this patch. Tested-by: Vlad Buslov <vladbu@nvidia.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-31Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Andrii Nakryiko says: ==================== bpf-next 2021-07-30 We've added 64 non-merge commits during the last 15 day(s) which contain a total of 83 files changed, 5027 insertions(+), 1808 deletions(-). The main changes are: 1) BTF-guided binary data dumping libbpf API, from Alan. 2) Internal factoring out of libbpf CO-RE relocation logic, from Alexei. 3) Ambient BPF run context and cgroup storage cleanup, from Andrii. 4) Few small API additions for libbpf 1.0 effort, from Evgeniy and Hengqi. 5) bpf_program__attach_kprobe_opts() fixes in libbpf, from Jiri. 6) bpf_{get,set}sockopt() support in BPF iterators, from Martin. 7) BPF map pinning improvements in libbpf, from Martynas. 8) Improved module BTF support in libbpf and bpftool, from Quentin. 9) Bpftool cleanups and documentation improvements, from Quentin. 10) Libbpf improvements for supporting CO-RE on old kernels, from Shuyi. 11) Increased maximum cgroup storage size, from Stanislav. 12) Small fixes and improvements to BPF tests and samples, from various folks. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (64 commits) tools: bpftool: Complete metrics list in "bpftool prog profile" doc tools: bpftool: Document and add bash completion for -L, -B options selftests/bpf: Update bpftool's consistency script for checking options tools: bpftool: Update and synchronise option list in doc and help msg tools: bpftool: Complete and synchronise attach or map types selftests/bpf: Check consistency between bpftool source, doc, completion tools: bpftool: Slightly ease bash completion updates unix_bpf: Fix a potential deadlock in unix_dgram_bpf_recvmsg() libbpf: Add btf__load_vmlinux_btf/btf__load_module_btf tools: bpftool: Support dumping split BTF by id libbpf: Add split BTF support for btf__load_from_kernel_by_id() tools: Replace btf__get_from_id() with btf__load_from_kernel_by_id() tools: Free BTF objects at various locations libbpf: Rename btf__get_from_id() as btf__load_from_kernel_by_id() libbpf: Rename btf__load() as btf__load_into_kernel() libbpf: Return non-null error on failures in libbpf_find_prog_btf_id() bpf: Emit better log message if bpf_iter ctx arg btf_id == 0 tools/resolve_btfids: Emit warnings and patch zero id for missing symbols bpf: Increase supported cgroup storage value size libbpf: Fix race when pinning maps in parallel ... ==================== Link: https://lore.kernel.org/r/20210730225606.1897330-1-andrii@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicting commits, all resolutions pretty trivial: drivers/bus/mhi/pci_generic.c 5c2c85315948 ("bus: mhi: pci-generic: configurable network interface MRU") 56f6f4c4eb2a ("bus: mhi: pci_generic: Apply no-op for wake using sideband wake boolean") drivers/nfc/s3fwrn5/firmware.c a0302ff5906a ("nfc: s3fwrn5: remove unnecessary label") 46573e3ab08f ("nfc: s3fwrn5: fix undefined parameter values in dev_err()") 801e541c79bb ("nfc: s3fwrn5: fix undefined parameter values in dev_err()") MAINTAINERS 7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver") 8a7b46fa7902 ("MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30Merge tag 'net-5.14-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Networking fixes for 5.14-rc4, including fixes from bpf, can, WiFi (mac80211) and netfilter trees. Current release - regressions: - mac80211: fix starting aggregation sessions on mesh interfaces Current release - new code bugs: - sctp: send pmtu probe only if packet loss in Search Complete state - bnxt_en: add missing periodic PHC overflow check - devlink: fix phys_port_name of virtual port and merge error - hns3: change the method of obtaining default ptp cycle - can: mcba_usb_start(): add missing urb->transfer_dma initialization Previous releases - regressions: - set true network header for ECN decapsulation - mlx5e: RX, avoid possible data corruption w/ relaxed ordering and LRO - phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811 PHY - sctp: fix return value check in __sctp_rcv_asconf_lookup Previous releases - always broken: - bpf: - more spectre corner case fixes, introduce a BPF nospec instruction for mitigating Spectre v4 - fix OOB read when printing XDP link fdinfo - sockmap: fix cleanup related races - mac80211: fix enabling 4-address mode on a sta vif after assoc - can: - raw: raw_setsockopt(): fix raw_rcv panic for sock UAF - j1939: j1939_session_deactivate(): clarify lifetime of session object, avoid UAF - fix number of identical memory leaks in USB drivers - tipc: - do not blindly write skb_shinfo frags when doing decryption - fix sleeping in tipc accept routine" * tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits) gve: Update MAINTAINERS list can: esd_usb2: fix memory leak can: ems_usb: fix memory leak can: usb_8dev: fix memory leak can: mcba_usb_start(): add missing urb->transfer_dma initialization can: hi311x: fix a signedness bug in hi3110_cmd() MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver bpf: Fix leakage due to insufficient speculative store bypass mitigation bpf: Introduce BPF nospec instruction for mitigating Spectre v4 sis900: Fix missing pci_disable_device() in probe and remove net: let flow have same hash in two directions nfc: nfcsim: fix use after free during module unload tulip: windbond-840: Fix missing pci_disable_device() in probe and remove sctp: fix return value check in __sctp_rcv_asconf_lookup nfc: s3fwrn5: fix undefined parameter values in dev_err() net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32 net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev() net/mlx5: Unload device upon firmware fatal error net/mlx5e: Fix page allocation failure for ptp-RQ over SF net/mlx5e: Fix page allocation failure for trap-RQ over SF ...
2021-07-30devlink: Allocate devlink directly in requested net namespaceLeon Romanovsky
There is no need in extra call indirection and check from impossible flow where someone tries to set namespace without prior call to devlink_alloc(). Instead of this extra logic and additional EXPORT_SYMBOL, use specialized devlink allocation function that receives net namespace as an argument. Such specialized API allows clear view when devlink initialized in wrong net namespace and/or kernel users don't try to change devlink namespace under the hood. Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30sk_buff: avoid potentially clearing 'slow_gro' fieldPaolo Abeni
If skb_dst_set_noref() is invoked with a NULL dst, the 'slow_gro' field is cleared, too. That could lead to wrong behavior if the skb later enters the GRO stage. Fix the potential issue replacing preserving a non-zero value of the 'slow_gro' field. Additionally, fix a comment typo. Reported-by: Sabrina Dubroca <sd@queasysnail.net> Reported-by: Jakub Kicinski <kuba@kernel.org> Fixes: 8a886b142bd0 ("sk_buff: track dst status in slow_gro") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/aa42529252dc8bb02bd42e8629427040d1058537.1627662501.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid Pull HID fixes from Jiri Kosina: - resume timing fix for intel-ish driver (Ye Xiang) - fix for using incorrect MMIO register in amd_sfh driver (Dylan MacKenzie) - Cintiq 24HDT / 27QHDT regression fix and touch processing fix for Wacom driver (Jason Gerecke) - device removal bugfix for ft260 driver (Michael Zaidman) - other small assorted fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: HID: ft260: fix device removal due to USB disconnect HID: wacom: Skip processing of touches with negative slot values HID: wacom: Re-enable touch by default for Cintiq 24HDT / 27QHDT HID: Kconfig: Fix spelling mistake "Uninterruptable" -> "Uninterruptible" HID: apple: Add support for Keychron K1 wireless keyboard HID: fix typo in Kconfig HID: ft260: fix format type warning in ft260_word_show() HID: amd_sfh: Use correct MMIO register for DMA address HID: asus: Remove check for same LED brightness on set HID: intel-ish-hid: use async resume function
2021-07-30net: netlink: Remove unused functionYajun Deng
lockdep_genl_is_held() and its caller arm not used now, just remove them. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Link: https://lore.kernel.org/r/20210729074854.8968-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30nfc: nci: constify several pointers to u8, sk_buff and other structsKrzysztof Kozlowski
Several functions receive pointers to u8, sk_buff or other structs but do not modify the contents so make them const. This allows doing the same for local variables and in total makes the code a little bit safer. This makes const also data passed as "unsigned long opt" argument to nci_request() function. Usual flow for such functions is: 1. Receive "u8 *" and store it (the pointer) in a structure allocated on stack (e.g. struct nci_set_config_param), 2. Call nci_request() or __nci_request() passing a callback function an the pointer to the structure via an "unsigned long opt", 3. nci_request() calls the callback which dereferences "unsigned long opt" in a read-only way. This converts all above paths to use proper pointer to const data, so entire flow is safer. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30nfc: constify several pointers to u8, char and sk_buffKrzysztof Kozlowski
Several functions receive pointers to u8, char or sk_buff but do not modify the contents so make them const. This allows doing the same for local variables and in total makes the code a little bit safer. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30net: convert fib_treeref from int to refcount_tYajun Deng
refcount_t type should be used instead of int when fib_treeref is used as a reference counter,and avoid use-after-free risks. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210729071350.28919-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-29net/sched: store the last executed chain also for clsact egressDavide Caratti
currently, only 'ingress' and 'clsact ingress' qdiscs store the tc 'chain id' in the skb extension. However, userspace programs (like ovs) are able to setup egress rules, and datapath gets confused in case it doesn't find the 'chain id' for a packet that's "recirculated" by tc. Change tcf_classify() to have the same semantic as tcf_classify_ingress() so that a single function can be called in ingress / egress, using the tc ingress / egress block respectively. Suggested-by: Alaa Hleilel <alaa@nvidia.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Allow per-netns default networksMatt Johnston
Currently we have a compile-time default network (MCTP_INITIAL_DEFAULT_NET). This change introduces a default_net field on the net namespace, allowing future configuration for new interfaces. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Implement message fragmentation & reassemblyJeremy Kerr
This change implements MCTP fragmentation (based on route & device MTU), and corresponding reassembly. The MCTP specification only allows for fragmentation on the originating message endpoint, and reassembly on the destination endpoint - intermediate nodes do not need to reassemble/refragment. Consequently, we only fragment in the local transmit path, and reassemble locally-bound packets. Messages are required to be in-order, so we simply cancel reassembly on out-of-order or missing packets. In the fragmentation path, we just break up the message into MTU-sized fragments; the skb structure is a simple copy for now, which we can later improve with a shared data implementation. For reassembly, we keep track of incoming message fragments using the existing tag infrastructure, allocating a key on the (src,dest,tag) tuple, and reassembles matching fragments into a skb->frag_list. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Populate socket implementationJeremy Kerr
Start filling-out the socket syscalls: bind, sendmsg & recvmsg. This requires an input route implementation, so we add to mctp_route_input, allowing lookups on binds & message tags. This just handles single-packet messages at present, we will add fragmentation in a future change. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add neighbour implementationMatt Johnston
Add an initial neighbour table implementation, to be used in the route output path. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add netlink route managementMatt Johnston
This change adds RTM_GETROUTE, RTM_NEWROUTE & RTM_DELROUTE handlers, allowing management of the MCTP route table. Includes changes from Jeremy Kerr <jk@codeconstruct.com.au>. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add initial routing frameworkJeremy Kerr
Add a simple routing table, and a couple of route output handlers, and the mctp packet_type & handler. Includes changes from Matt Johnston <matt@codeconstruct.com.au>. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add device handling and netlink interfaceJeremy Kerr
This change adds the infrastructure for managing MCTP netdevices; we add a pointer to the AF_MCTP-specific data to struct netdevice, and hook up the rtnetlink operations for adding and removing addresses. Includes changes from Matt Johnston <matt@codeconstruct.com.au>. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add initial driver infrastructureJeremy Kerr
Add an empty drivers/net/mctp/, for future interface drivers. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add sockaddr_mctp to uapiJeremy Kerr
This change introduces the user-visible MCTP header, containing the protocol-specific addressing definitions. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add base packet definitionsJeremy Kerr
Simple packet header format as defined by DMTF DSP0236. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29mctp: Add MCTP baseJeremy Kerr
Add basic Kconfig, an initial (empty) af_mctp source object, and {AF,PF}_MCTP definitions, and the required definitions for a new protocol type. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29nfc: constify passed nfc_devKrzysztof Kozlowski
The struct nfc_dev is not modified by nfc_get_drvdata() and nfc_device_name() so it can be made a const. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29skbuff: allow 'slow_gro' for skb carring sock referencePaolo Abeni
This change leverages the infrastructure introduced by the previous patches to allow soft devices passing to the GRO engine owned skbs without impacting the fast-path. It's up to the GRO caller ensuring the slow_gro bit validity before invoking the GRO engine. The new helper skb_prepare_for_gro() is introduced for that goal. On slow_gro, skbs are aggregated only with equal sk. Additionally, skb truesize on GRO recycle and free is correctly updated so that sk wmem is not changed by the GRO processing. rfc-> v1: - fixed bad truesize on dev_gro_receive NAPI_FREE - use the existing state bit Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29sk_buff: track dst status in slow_groPaolo Abeni
Similar to the previous patch, but covering the dst field: the slow_gro flag is additionally set when a dst is attached to the skb RFC -> v1: - use the existing flag instead of adding a new one Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29sk_buff: introduce 'slow_gro' flagsPaolo Abeni
The new flag tracks if any state field is set, so that GRO requires 'unusual'/slow prepare steps. Set such flag when a ct entry is attached to the skb, and never clear it. The new bit uses an existing hole into the sk_buff struct RFC -> v1: - use a single state bit, never clear it - avoid moving the _nfct field Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2021-07-29 The following pull-request contains BPF updates for your *net* tree. We've added 9 non-merge commits during the last 14 day(s) which contain a total of 20 files changed, 446 insertions(+), 138 deletions(-). The main changes are: 1) Fix UBSAN out-of-bounds splat for showing XDP link fdinfo, from Lorenz Bauer. 2) Fix insufficient Spectre v4 mitigation in BPF runtime, from Daniel Borkmann, Piotr Krysiuk and Benedict Schlueter. 3) Batch of fixes for BPF sockmap found under stress testing, from John Fastabend. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29bpf: Fix leakage due to insufficient speculative store bypass mitigationDaniel Borkmann
Spectre v4 gadgets make use of memory disambiguation, which is a set of techniques that execute memory access instructions, that is, loads and stores, out of program order; Intel's optimization manual, section 2.4.4.5: A load instruction micro-op may depend on a preceding store. Many microarchitectures block loads until all preceding store addresses are known. The memory disambiguator predicts which loads will not depend on any previous stores. When the disambiguator predicts that a load does not have such a dependency, the load takes its data from the L1 data cache. Eventually, the prediction is verified. If an actual conflict is detected, the load and all succeeding instructions are re-executed. af86ca4e3088 ("bpf: Prevent memory disambiguation attack") tried to mitigate this attack by sanitizing the memory locations through preemptive "fast" (low latency) stores of zero prior to the actual "slow" (high latency) store of a pointer value such that upon dependency misprediction the CPU then speculatively executes the load of the pointer value and retrieves the zero value instead of the attacker controlled scalar value previously stored at that location, meaning, subsequent access in the speculative domain is then redirected to the "zero page". The sanitized preemptive store of zero prior to the actual "slow" store is done through a simple ST instruction based on r10 (frame pointer) with relative offset to the stack location that the verifier has been tracking on the original used register for STX, which does not have to be r10. Thus, there are no memory dependencies for this store, since it's only using r10 and immediate constant of zero; hence af86ca4e3088 /assumed/ a low latency operation. However, a recent attack demonstrated that this mitigation is not sufficient since the preemptive store of zero could also be turned into a "slow" store and is thus bypassed as well: [...] // r2 = oob address (e.g. scalar) // r7 = pointer to map value 31: (7b) *(u64 *)(r10 -16) = r2 // r9 will remain "fast" register, r10 will become "slow" register below 32: (bf) r9 = r10 // JIT maps BPF reg to x86 reg: // r9 -> r15 (callee saved) // r10 -> rbp // train store forward prediction to break dependency link between both r9 // and r10 by evicting them from the predictor's LRU table. 33: (61) r0 = *(u32 *)(r7 +24576) 34: (63) *(u32 *)(r7 +29696) = r0 35: (61) r0 = *(u32 *)(r7 +24580) 36: (63) *(u32 *)(r7 +29700) = r0 37: (61) r0 = *(u32 *)(r7 +24584) 38: (63) *(u32 *)(r7 +29704) = r0 39: (61) r0 = *(u32 *)(r7 +24588) 40: (63) *(u32 *)(r7 +29708) = r0 [...] 543: (61) r0 = *(u32 *)(r7 +25596) 544: (63) *(u32 *)(r7 +30716) = r0 // prepare call to bpf_ringbuf_output() helper. the latter will cause rbp // to spill to stack memory while r13/r14/r15 (all callee saved regs) remain // in hardware registers. rbp becomes slow due to push/pop latency. below is // disasm of bpf_ringbuf_output() helper for better visual context: // // ffffffff8117ee20: 41 54 push r12 // ffffffff8117ee22: 55 push rbp // ffffffff8117ee23: 53 push rbx // ffffffff8117ee24: 48 f7 c1 fc ff ff ff test rcx,0xfffffffffffffffc // ffffffff8117ee2b: 0f 85 af 00 00 00 jne ffffffff8117eee0 <-- jump taken // [...] // ffffffff8117eee0: 49 c7 c4 ea ff ff ff mov r12,0xffffffffffffffea // ffffffff8117eee7: 5b pop rbx // ffffffff8117eee8: 5d pop rbp // ffffffff8117eee9: 4c 89 e0 mov rax,r12 // ffffffff8117eeec: 41 5c pop r12 // ffffffff8117eeee: c3 ret 545: (18) r1 = map[id:4] 547: (bf) r2 = r7 548: (b7) r3 = 0 549: (b7) r4 = 4 550: (85) call bpf_ringbuf_output#194288 // instruction 551 inserted by verifier \ 551: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here // storing map value pointer r7 at fp-16 | since value of r10 is "slow". 552: (7b) *(u64 *)(r10 -16) = r7 / // following "fast" read to the same memory location, but due to dependency // misprediction it will speculatively execute before insn 551/552 completes. 553: (79) r2 = *(u64 *)(r9 -16) // in speculative domain contains attacker controlled r2. in non-speculative // domain this contains r7, and thus accesses r7 +0 below. 554: (71) r3 = *(u8 *)(r2 +0) // leak r3 As can be seen, the current speculative store bypass mitigation which the verifier inserts at line 551 is insufficient since /both/, the write of the zero sanitation as well as the map value pointer are a high latency instruction due to prior memory access via push/pop of r10 (rbp) in contrast to the low latency read in line 553 as r9 (r15) which stays in hardware registers. Thus, architecturally, fp-16 is r7, however, microarchitecturally, fp-16 can still be r2. Initial thoughts to address this issue was to track spilled pointer loads from stack and enforce their load via LDX through r10 as well so that /both/ the preemptive store of zero /as well as/ the load use the /same/ register such that a dependency is created between the store and load. However, this option is not sufficient either since it can be bypassed as well under speculation. An updated attack with pointer spill/fills now _all_ based on r10 would look as follows: [...] // r2 = oob address (e.g. scalar) // r7 = pointer to map value [...] // longer store forward prediction training sequence than before. 2062: (61) r0 = *(u32 *)(r7 +25588) 2063: (63) *(u32 *)(r7 +30708) = r0 2064: (61) r0 = *(u32 *)(r7 +25592) 2065: (63) *(u32 *)(r7 +30712) = r0 2066: (61) r0 = *(u32 *)(r7 +25596) 2067: (63) *(u32 *)(r7 +30716) = r0 // store the speculative load address (scalar) this time after the store // forward prediction training. 2068: (7b) *(u64 *)(r10 -16) = r2 // preoccupy the CPU store port by running sequence of dummy stores. 2069: (63) *(u32 *)(r7 +29696) = r0 2070: (63) *(u32 *)(r7 +29700) = r0 2071: (63) *(u32 *)(r7 +29704) = r0 2072: (63) *(u32 *)(r7 +29708) = r0 2073: (63) *(u32 *)(r7 +29712) = r0 2074: (63) *(u32 *)(r7 +29716) = r0 2075: (63) *(u32 *)(r7 +29720) = r0 2076: (63) *(u32 *)(r7 +29724) = r0 2077: (63) *(u32 *)(r7 +29728) = r0 2078: (63) *(u32 *)(r7 +29732) = r0 2079: (63) *(u32 *)(r7 +29736) = r0 2080: (63) *(u32 *)(r7 +29740) = r0 2081: (63) *(u32 *)(r7 +29744) = r0 2082: (63) *(u32 *)(r7 +29748) = r0 2083: (63) *(u32 *)(r7 +29752) = r0 2084: (63) *(u32 *)(r7 +29756) = r0 2085: (63) *(u32 *)(r7 +29760) = r0 2086: (63) *(u32 *)(r7 +29764) = r0 2087: (63) *(u32 *)(r7 +29768) = r0 2088: (63) *(u32 *)(r7 +29772) = r0 2089: (63) *(u32 *)(r7 +29776) = r0 2090: (63) *(u32 *)(r7 +29780) = r0 2091: (63) *(u32 *)(r7 +29784) = r0 2092: (63) *(u32 *)(r7 +29788) = r0 2093: (63) *(u32 *)(r7 +29792) = r0 2094: (63) *(u32 *)(r7 +29796) = r0 2095: (63) *(u32 *)(r7 +29800) = r0 2096: (63) *(u32 *)(r7 +29804) = r0 2097: (63) *(u32 *)(r7 +29808) = r0 2098: (63) *(u32 *)(r7 +29812) = r0 // overwrite scalar with dummy pointer; same as before, also including the // sanitation store with 0 from the current mitigation by the verifier. 2099: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here 2100: (7b) *(u64 *)(r10 -16) = r7 | since store unit is still busy. // load from stack intended to bypass stores. 2101: (79) r2 = *(u64 *)(r10 -16) 2102: (71) r3 = *(u8 *)(r2 +0) // leak r3 [...] Looking at the CPU microarchitecture, the scheduler might issue loads (such as seen in line 2101) before stores (line 2099,2100) because the load execution units become available while the store execution unit is still busy with the sequence of dummy stores (line 2069-2098). And so the load may use the prior stored scalar from r2 at address r10 -16 for speculation. The updated attack may work less reliable on CPU microarchitectures where loads and stores share execution resources. This concludes that the sanitizing with zero stores from af86ca4e3088 ("bpf: Prevent memory disambiguation attack") is insufficient. Moreover, the detection of stack reuse from af86ca4e3088 where previously data (STACK_MISC) has been written to a given stack slot where a pointer value is now to be stored does not have sufficient coverage as precondition for the mitigation either; for several reasons outlined as follows: 1) Stack content from prior program runs could still be preserved and is therefore not "random", best example is to split a speculative store bypass attack between tail calls, program A would prepare and store the oob address at a given stack slot and then tail call into program B which does the "slow" store of a pointer to the stack with subsequent "fast" read. From program B PoV such stack slot type is STACK_INVALID, and therefore also must be subject to mitigation. 2) The STACK_SPILL must not be coupled to register_is_const(&stack->spilled_ptr) condition, for example, the previous content of that memory location could also be a pointer to map or map value. Without the fix, a speculative store bypass is not mitigated in such precondition and can then lead to a type confusion in the speculative domain leaking kernel memory near these pointer types. While brainstorming on various alternative mitigation possibilities, we also stumbled upon a retrospective from Chrome developers [0]: [...] For variant 4, we implemented a mitigation to zero the unused memory of the heap prior to allocation, which cost about 1% when done concurrently and 4% for scavenging. Variant 4 defeats everything we could think of. We explored more mitigations for variant 4 but the threat proved to be more pervasive and dangerous than we anticipated. For example, stack slots used by the register allocator in the optimizing compiler could be subject to type confusion, leading to pointer crafting. Mitigating type confusion for stack slots alone would have required a complete redesign of the backend of the optimizing compiler, perhaps man years of work, without a guarantee of completeness. [...] From BPF side, the problem space is reduced, however, options are rather limited. One idea that has been explored was to xor-obfuscate pointer spills to the BPF stack: [...] // preoccupy the CPU store port by running sequence of dummy stores. [...] 2106: (63) *(u32 *)(r7 +29796) = r0 2107: (63) *(u32 *)(r7 +29800) = r0 2108: (63) *(u32 *)(r7 +29804) = r0 2109: (63) *(u32 *)(r7 +29808) = r0 2110: (63) *(u32 *)(r7 +29812) = r0 // overwrite scalar with dummy pointer; xored with random 'secret' value // of 943576462 before store ... 2111: (b4) w11 = 943576462 2112: (af) r11 ^= r7 2113: (7b) *(u64 *)(r10 -16) = r11 2114: (79) r11 = *(u64 *)(r10 -16) 2115: (b4) w2 = 943576462 2116: (af) r2 ^= r11 // ... and restored with the same 'secret' value with the help of AX reg. 2117: (71) r3 = *(u8 *)(r2 +0) [...] While the above would not prevent speculation, it would make data leakage infeasible by directing it to random locations. In order to be effective and prevent type confusion under speculation, such random secret would have to be regenerated for each store. The additional complexity involved for a tracking mechanism that prevents jumps such that restoring spilled pointers would not get corrupted is not worth the gain for unprivileged. Hence, the fix in here eventually opted for emitting a non-public BPF_ST | BPF_NOSPEC instruction which the x86 JIT translates into a lfence opcode. Inserting the latter in between the store and load instruction is one of the mitigations options [1]. The x86 instruction manual notes: [...] An LFENCE that follows an instruction that stores to memory might complete before the data being stored have become globally visible. [...] The latter meaning that the preceding store instruction finished execution and the store is at minimum guaranteed to be in the CPU's store queue, but it's not guaranteed to be in that CPU's L1 cache at that point (globally visible). The latter would only be guaranteed via sfence. So the load which is guaranteed to execute after the lfence for that local CPU would have to rely on store-to-load forwarding. [2], in section 2.3 on store buffers says: [...] For every store operation that is added to the ROB, an entry is allocated in the store buffer. This entry requires both the virtual and physical address of the target. Only if there is no free entry in the store buffer, the frontend stalls until there is an empty slot available in the store buffer again. Otherwise, the CPU can immediately continue adding subsequent instructions to the ROB and execute them out of order. On Intel CPUs, the store buffer has up to 56 entries. [...] One small upside on the fix is that it lifts constraints from af86ca4e3088 where the sanitize_stack_off relative to r10 must be the same when coming from different paths. The BPF_ST | BPF_NOSPEC gets emitted after a BPF_STX or BPF_ST instruction. This happens either when we store a pointer or data value to the BPF stack for the first time, or upon later pointer spills. The former needs to be enforced since otherwise stale stack data could be leaked under speculation as outlined earlier. For non-x86 JITs the BPF_ST | BPF_NOSPEC mapping is currently optimized away, but others could emit a speculation barrier as well if necessary. For real-world unprivileged programs e.g. generated by LLVM, pointer spill/fill is only generated upon register pressure and LLVM only tries to do that for pointers which are not used often. The program main impact will be the initial BPF_ST | BPF_NOSPEC sanitation for the STACK_INVALID case when the first write to a stack slot occurs e.g. upon map lookup. In future we might refine ways to mitigate the latter cost. [0] https://arxiv.org/pdf/1902.05178.pdf [1] https://msrc-blog.microsoft.com/2018/05/21/analysis-and-mitigation-of-speculative-store-bypass-cve-2018-3639/ [2] https://arxiv.org/pdf/1905.05725.pdf Fixes: af86ca4e3088 ("bpf: Prevent memory disambiguation attack") Fixes: f7cf25b2026d ("bpf: track spill/fill of constants") Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-07-29bpf: Introduce BPF nospec instruction for mitigating Spectre v4Daniel Borkmann
In case of JITs, each of the JIT backends compiles the BPF nospec instruction /either/ to a machine instruction which emits a speculation barrier /or/ to /no/ machine instruction in case the underlying architecture is not affected by Speculative Store Bypass or has different mitigations in place already. This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence' instruction for mitigation. In case of arm64, we rely on the firmware mitigation as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled, it works for all of the kernel code with no need to provide any additional instructions here (hence only comment in arm64 JIT). Other archs can follow as needed. The BPF nospec instruction is specifically targeting Spectre v4 since i) we don't use a serialization barrier for the Spectre v1 case, and ii) mitigation instructions for v1 and v4 might be different on some archs. The BPF nospec is required for a future commit, where the BPF verifier does annotate intermediate BPF programs with speculation barriers. Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-07-28dmaengine: idxd: Change license on idxd.h to LGPLTony Luck
This file was given GPL-2.0 license. But LGPL-2.1 makes more sense as it needs to be used by libraries outside of the kernel source tree. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>