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2020-02-28bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fillJohannes Krude1-1/+1
commit e20d3a055a457a10a4c748ce5b7c2ed3173a1324 upstream. This if guards whether user-space wants a copy of the offload-jited bytecode and whether this bytecode exists. By erroneously doing a bitwise AND instead of a logical AND on user- and kernel-space buffer-size can lead to no data being copied to user-space especially when user-space size is a power of two and bigger then the kernel-space buffer. Fixes: fcfb126defda ("bpf: add new jited info fields in bpf_dev_offload and bpf_prog_info") Signed-off-by: Johannes Krude <johannes@krude.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20200212193227.GA3769@phlox.h.transitiv.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-27bpf, offload: Unlock on error in bpf_offload_dev_create()Dan Carpenter1-1/+3
[ Upstream commit d0fbb51dfaa612f960519b798387be436e8f83c5 ] We need to drop the bpf_devs_lock on error before returning. Fixes: 9fd7c5559165 ("bpf: offload: aggregate offloads per-device") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Link: https://lore.kernel.org/bpf/20191104091536.GB31509@mwanda Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-07-18bpf: offload: allow program and map sharing per-ASICJakub Kicinski1-7/+35
Allow programs and maps to be re-used across different netdevs, as long as they belong to the same struct bpf_offload_dev. Update the bpf_offload_prog_map_match() helper for the verifier and export a new helper for the drivers to use when checking programs at attachment time. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-18bpf: offload: keep the offload state per-ASICJakub Kicinski1-17/+64
Create a higher-level entity to represent a device/ASIC to allow programs and maps to be shared between device ports. The extra work is required to make sure we don't destroy BPF objects as soon as the netdev for which they were loaded gets destroyed, as other ports may still be using them. When netdev goes away all of its BPF objects will be moved to other netdevs of the device, and only destroyed when last netdev is unregistered. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-18bpf: offload: aggregate offloads per-deviceJakub Kicinski1-46/+96
Currently we have two lists of offloaded objects - programs and maps. Netdevice unregister notifier scans those lists to orphan objects associated with device being unregistered. This puts unnecessary (even if negligible) burden on all netdev unregister calls in BPF- -enabled kernel. The lists of objects may potentially get long making the linear scan even more problematic. There haven't been complaints about this mechanisms so far, but it is suboptimal. Instead of relying on notifiers, make the few BPF-capable drivers register explicitly for BPF offloads. The programs and maps will now be collected per-device not on a global list, and only scanned for removal when driver unregisters from BPF offloads. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-18bpf: offload: rename bpf_offload_dev_match() to bpf_offload_prog_map_match()Jakub Kicinski1-1/+1
A set of new API functions exported for the drivers will soon use 'bpf_offload_dev_' as a prefix. Rename the bpf_offload_dev_match() which is internal to the core (used by the verifier) to avoid any confusion. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04bpf: offload: allow offloaded programs to use perf event arraysJakub Kicinski1-2/+4
BPF_MAP_TYPE_PERF_EVENT_ARRAY is special as far as offload goes. The map only holds glue to perf ring, not actual data. Allow non-offloaded perf event arrays to be used in offloaded programs. Offload driver can extract the events from HW and put them in the map for user space to retrieve. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-18bpf: offload: report device information about offloaded mapsJakub Kicinski1-0/+55
Tell user space about device on which the map was created. Unfortunate reality of user ABI makes sharing this code with program offload difficult but the information is the same. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-18bpf: offload: allow array map offloadJakub Kicinski1-1/+2
The special handling of different map types is left to the driver. Allow offload of array maps by simply adding it to accepted types. For nfp we have to make sure array elements are not deleted. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-18bpf: add new jited info fields in bpf_dev_offload and bpf_prog_infoJiong Wang1-0/+23
For host JIT, there are "jited_len"/"bpf_func" fields in struct bpf_prog used by all host JIT targets to get jited image and it's length. While for offload, targets are likely to have different offload mechanisms that these info are kept in device private data fields. Therefore, BPF_OBJ_GET_INFO_BY_FD syscall needs an unified way to get JIT length and contents info for offload targets. One way is to introduce new callback to parse device private data then fill those fields in bpf_prog_info. This might be a little heavy, the other way is to add generic fields which will be initialized by all offload targets. This patch follow the second approach to introduce two new fields in struct bpf_dev_offload and teach bpf_prog_get_info_by_fd about them to fill correct jited_prog_len and jited_prog_insns in bpf_prog_info. Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-17bpf: offload: make bpf_offload_dev_match() reject host+host caseJakub Kicinski1-3/+1
Daniel suggests it would be more logical for bpf_offload_dev_match() to return false is either the program or the map are not offloaded, rather than treating the both not offloaded case as a "matching CPU/host device". This makes no functional difference today, since verifier only calls bpf_offload_dev_match() when one of the objects is offloaded. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-14bpf: offload: add map offload infrastructureJakub Kicinski1-7/+181
BPF map offload follow similar path to program offload. At creation time users may specify ifindex of the device on which they want to create the map. Map will be validated by the kernel's .map_alloc_check callback and device driver will be called for the actual allocation. Map will have an empty set of operations associated with it (save for alloc and free callbacks). The real device callbacks are kept in map->offload->dev_ops because they have slightly different signatures. Map operations are called in process context so the driver may communicate with HW freely, msleep(), wait() etc. Map alloc and free callbacks are muxed via existing .ndo_bpf, and are always called with rtnl lock held. Maps and programs are guaranteed to be destroyed before .ndo_uninit (i.e. before unregister_netdev() returns). Map callbacks are invoked with bpf_devs_lock *read* locked, drivers must take care of exclusive locking if necessary. All offload-specific branches are marked with unlikely() (through bpf_map_is_dev_bound()), given that branch penalty will be negligible compared to IO anyway, and we don't want to penalize SW path unnecessarily. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-14bpf: offload: factor out netdev checking at allocation timeJakub Kicinski1-8/+20
Add a helper to check if netdev could be found and whether it has .ndo_bpf callback. There is no need to check the callback every time it's invoked, ndos can't reasonably be swapped for a set without .ndp_bpf while program is loaded. bpf_dev_offload_check() will also be used by map offload. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-14bpf: rename bpf_dev_offload -> bpf_prog_offloadJakub Kicinski1-5/+5
With map offload coming, we need to call program offload structure something less ambiguous. Pure rename, no functional changes. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31bpf: offload: report device information for offloaded programsJakub Kicinski1-0/+59
Report to the user ifindex and namespace information of offloaded programs. If device has disappeared return -ENODEV. Specify the namespace using dev/inode combination. CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31bpf: offload: free program id when device disappearsJakub Kicinski1-0/+3
Bound programs are quite useless after their device disappears. They are simply waiting for reference count to go to zero, don't list them in BPF_PROG_GET_NEXT_ID by freeing their ID early. Note that orphaned offload programs will return -ENODEV on BPF_OBJ_GET_INFO_BY_FD so user will never see ID 0. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31bpf: offload: free prog->aux->offload when device disappearsJakub Kicinski1-14/+9
All bpf offload operations should now be under bpf_devs_lock, it's safe to free and clear the entire offload structure, not only the netdev pointer. __bpf_prog_offload_destroy() will no longer be called multiple times. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31bpf: offload: allow netdev to disappear while verifier is runningJakub Kicinski1-14/+16
To allow verifier instruction callbacks without any extra locking NETDEV_UNREGISTER notification would wait on a waitqueue for verifier to finish. This design decision was made when rtnl lock was providing all the locking. Use the read/write lock instead and remove the workqueue. Verifier will now call into the offload code, so dev_ops are moved to offload structure. Since verifier calls are all under bpf_prog_is_dev_bound() we no longer need static inline implementations to please builds with CONFIG_NET=n. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31bpf: offload: don't require rtnl for dev list manipulationJakub Kicinski1-10/+24
We don't need the RTNL lock for all operations on offload state. We only need to hold it around ndo calls. The device offload initialization doesn't require it. The soon-to-come querying of the offload info will only need it partially. We will also be able to remove the waitqueue in following patches. Use struct rw_semaphore because map offload will require sleeping with the semaphore held for read. Suggested-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-27bpf: offload: add a license headerJakub Kicinski1-0/+15
I forgot to add a license on kernel/bpf/offload.c. Luckily I'm still the only author so make it explicitly GPLv2. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: revert report offload info to user spaceJakub Kicinski1-12/+0
This reverts commit bd601b6ada11 ("bpf: report offload info to user space"). The ifindex by itself is not sufficient, we should provide information on which network namespace this ifindex belongs to. After considering some options we concluded that it's best to just remove this API for now, and rework it in -next. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: offload: ignore namespace movesJakub Kicinski1-0/+4
We are currently destroying the device offload state when device moves to another net namespace. This doesn't break with current NFP code, because offload state is not used on program removal, but it's not correct behaviour. Ignore the device unregister notifications on namespace move. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: offload: rename the ifindex fieldJakub Kicinski1-1/+1
bpf_target_prog seems long and clunky, rename it to prog_ifindex. We don't want to call this field just ifindex, because maps may need a similar field in the future and bpf_attr members for programs and maps are unnamed. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: offload: limit offload to cls_bpf and xdp programs onlyJakub Kicinski1-2/+3
We are currently only allowing attachment of device-bound cls_bpf and XDP programs. Make this restriction explicit in the BPF offload code. This way we can potentially reuse the ifindex field in the future. Since XDP and cls_bpf programs can only be loaded by admin, we can drop the explicit capability check from offload code. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: offload: add comment warning developers about double destroyJakub Kicinski1-0/+4
Offload state may get destroyed either because the device for which it was constructed is going away, or because the refcount of bpf program itself has reached 0. In both of those cases we will call __bpf_prog_offload_destroy() to unlink the offload from the device. We may in fact call it twice, which works just fine, but we should make clear this is intended and caution others trying to extend the function. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-05bpf: report offload info to user spaceJakub Kicinski1-0/+12
Extend struct bpf_prog_info to contain information about program being bound to a device. Since the netdev may get destroyed while program still exists we need a flag to indicate the program is loaded for a device, even if the device is gone. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05bpf: offload: add infrastructure for loading programs for a specific netdevJakub Kicinski1-0/+182
The fact that we don't know which device the program is going to be used on is quite limiting in current eBPF infrastructure. We have to reverse or limit the changes which kernel makes to the loaded bytecode if we want it to be offloaded to a networking device. We also have to invent new APIs for debugging and troubleshooting support. Make it possible to load programs for a specific netdev. This helps us to bring the debug information closer to the core eBPF infrastructure (e.g. we will be able to reuse the verifer log in device JIT). It allows device JITs to perform translation on the original bytecode. __bpf_prog_get() when called to get a reference for an attachment point will now refuse to give it if program has a device assigned. Following patches will add a version of that function which passes the expected netdev in. @type argument in __bpf_prog_get() is renamed to attach_type to make it clearer that it's only set on attachment. All calls to ndo_bpf are protected by rtnl, only verifier callbacks are not. We need a wait queue to make sure netdev doesn't get destroyed while verifier is still running and calling its driver. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>