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2017-12-01bpf: set maximum number of attached progs to 64 for a single perf tpYonghong Song1-1/+2
cgropu+bpf prog array has a maximum number of 64 programs. Let us apply the same limit here. Fixes: e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-28bpf: 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>
2017-11-23bpf: fix branch pruning logicAlexei Starovoitov1-0/+27
when the verifier detects that register contains a runtime constant and it's compared with another constant it will prune exploration of the branch that is guaranteed not to be taken at runtime. This is all correct, but malicious program may be constructed in such a way that it always has a constant comparison and the other branch is never taken under any conditions. In this case such path through the program will not be explored by the verifier. It won't be taken at run-time either, but since all instructions are JITed the malicious program may cause JITs to complain about using reserved fields, etc. To fix the issue we have to track the instructions explored by the verifier and sanitize instructions that are dead at run time with NOPs. We cannot reject such dead code, since llvm generates it for valid C code, since it doesn't do as much data flow analysis as the verifier does. Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22bpf: introduce ARG_PTR_TO_MEM_OR_NULLGianluca Borello1-1/+3
With the current ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM semantics, an helper argument can be NULL when the next argument type is ARG_CONST_SIZE_OR_ZERO and the verifier can prove the value of this next argument is 0. However, most helpers are just interested in handling <!NULL, 0>, so forcing them to deal with <NULL, 0> makes the implementation of those helpers more complicated for no apparent benefits, requiring them to explicitly handle those corner cases with checks that bpf programs could start relying upon, preventing the possibility of removing them later. Solve this by making ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM never accept NULL even when ARG_CONST_SIZE_OR_ZERO is set, and introduce a new argument type ARG_PTR_TO_MEM_OR_NULL to explicitly deal with the NULL case. Currently, the only helper that needs this is bpf_csum_diff_proto(), so change arg1 and arg3 to this new type as well. Also add a new battery of tests that explicitly test the !ARG_PTR_TO_MEM_OR_NULL combination: all the current ones testing the various <NULL, 0> variations are focused on bpf_csum_diff, so cover also other helpers. Signed-off-by: Gianluca Borello <g.borello@gmail.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: revert report offload info to user spaceJakub Kicinski2-17/+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: turn bpf_prog_get_type() into a wrapperJakub Kicinski1-10/+0
bpf_prog_get_type() is identical to bpf_prog_get_type_dev(), with false passed as attach_drv. Instead of keeping it as an exported symbol turn it into static inline wrapper. 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: move offload device validation out to the driversJakub Kicinski1-11/+12
With TC shared block changes we can't depend on correct netdev pointer being available in cls_bpf. Move the device validation to the driver. Core will only make sure that offloaded programs are always attached in the driver (or in HW by the driver). We trust that drivers which implement offload callbacks will perform necessary checks. Moving the checks to the driver is generally a useful thing, in practice the check should be against a switchdev instance, not a netdev, given that most ASICs will probably allow using the same program on many ports. 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> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21bpf: offload: rename the ifindex fieldJakub Kicinski2-3/+3
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>
2017-11-16Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-6/+0
Merge updates from Andrew Morton: - a few misc bits - ocfs2 updates - almost all of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits) memory hotplug: fix comments when adding section mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP mm: simplify nodemask printing mm,oom_reaper: remove pointless kthread_run() error check mm/page_ext.c: check if page_ext is not prepared writeback: remove unused function parameter mm: do not rely on preempt_count in print_vma_addr mm, sparse: do not swamp log with huge vmemmap allocation failures mm/hmm: remove redundant variable align_end mm/list_lru.c: mark expected switch fall-through mm/shmem.c: mark expected switch fall-through mm/page_alloc.c: broken deferred calculation mm: don't warn about allocations which stall for too long fs: fuse: account fuse_inode slab memory as reclaimable mm, page_alloc: fix potential false positive in __zone_watermark_ok mm: mlock: remove lru_add_drain_all() mm, sysctl: make NUMA stats configurable shmem: convert shmem_init_inodecache() to void Unify migrate_pages and move_pages access checks mm, pagevec: rename pagevec drained field ...
2017-11-16kmemcheck: remove annotationsLevin, Alexander (Sasha Levin)1-6/+0
Patch series "kmemcheck: kill kmemcheck", v2. As discussed at LSF/MM, kill kmemcheck. KASan is a replacement that is able to work without the limitation of kmemcheck (single CPU, slow). KASan is already upstream. We are also not aware of any users of kmemcheck (or users who don't consider KASan as a suitable replacement). The only objection was that since KASAN wasn't supported by all GCC versions provided by distros at that time we should hold off for 2 years, and try again. Now that 2 years have passed, and all distros provide gcc that supports KASAN, kill kmemcheck again for the very same reasons. This patch (of 4): Remove kmemcheck annotations, and calls to kmemcheck from the kernel. [alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs] Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15bpf: fix lockdep splatEric Dumazet1-2/+6
pcpu_freelist_pop() needs the same lockdep awareness than pcpu_freelist_populate() to avoid a false positive. [ INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected ] switchto-defaul/12508 [HC0[0]:SC0[6]:HE0:SE0] is trying to acquire: (&htab->buckets[i].lock){......}, at: [<ffffffff9dc099cb>] __htab_percpu_map_update_elem+0x1cb/0x300 and this task is already holding: (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...}, at: [<ffffffff9e135848>] __dev_queue_xmit+0 x868/0x1240 which would create a new lock dependency: (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...} -> (&htab->buckets[i].lock){......} but this new dependency connects a SOFTIRQ-irq-safe lock: (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...} ... which became SOFTIRQ-irq-safe at: [<ffffffff9db5931b>] __lock_acquire+0x42b/0x1f10 [<ffffffff9db5b32c>] lock_acquire+0xbc/0x1b0 [<ffffffff9da05e38>] _raw_spin_lock+0x38/0x50 [<ffffffff9e135848>] __dev_queue_xmit+0x868/0x1240 [<ffffffff9e136240>] dev_queue_xmit+0x10/0x20 [<ffffffff9e1965d9>] ip_finish_output2+0x439/0x590 [<ffffffff9e197410>] ip_finish_output+0x150/0x2f0 [<ffffffff9e19886d>] ip_output+0x7d/0x260 [<ffffffff9e19789e>] ip_local_out+0x5e/0xe0 [<ffffffff9e197b25>] ip_queue_xmit+0x205/0x620 [<ffffffff9e1b8398>] tcp_transmit_skb+0x5a8/0xcb0 [<ffffffff9e1ba152>] tcp_write_xmit+0x242/0x1070 [<ffffffff9e1baffc>] __tcp_push_pending_frames+0x3c/0xf0 [<ffffffff9e1b3472>] tcp_rcv_established+0x312/0x700 [<ffffffff9e1c1acc>] tcp_v4_do_rcv+0x11c/0x200 [<ffffffff9e1c3dc2>] tcp_v4_rcv+0xaa2/0xc30 [<ffffffff9e191107>] ip_local_deliver_finish+0xa7/0x240 [<ffffffff9e191a36>] ip_local_deliver+0x66/0x200 [<ffffffff9e19137d>] ip_rcv_finish+0xdd/0x560 [<ffffffff9e191e65>] ip_rcv+0x295/0x510 [<ffffffff9e12ff88>] __netif_receive_skb_core+0x988/0x1020 [<ffffffff9e130641>] __netif_receive_skb+0x21/0x70 [<ffffffff9e1306ff>] process_backlog+0x6f/0x230 [<ffffffff9e132129>] net_rx_action+0x229/0x420 [<ffffffff9da07ee8>] __do_softirq+0xd8/0x43d [<ffffffff9e282bcc>] do_softirq_own_stack+0x1c/0x30 [<ffffffff9dafc2f5>] do_softirq+0x55/0x60 [<ffffffff9dafc3a8>] __local_bh_enable_ip+0xa8/0xb0 [<ffffffff9db4c727>] cpu_startup_entry+0x1c7/0x500 [<ffffffff9daab333>] start_secondary+0x113/0x140 to a SOFTIRQ-irq-unsafe lock: (&head->lock){+.+...} ... which became SOFTIRQ-irq-unsafe at: ... [<ffffffff9db5971f>] __lock_acquire+0x82f/0x1f10 [<ffffffff9db5b32c>] lock_acquire+0xbc/0x1b0 [<ffffffff9da05e38>] _raw_spin_lock+0x38/0x50 [<ffffffff9dc0b7fa>] pcpu_freelist_pop+0x7a/0xb0 [<ffffffff9dc08b2c>] htab_map_alloc+0x50c/0x5f0 [<ffffffff9dc00dc5>] SyS_bpf+0x265/0x1200 [<ffffffff9e28195f>] entry_SYSCALL_64_fastpath+0x12/0x17 other info that might help us debug this: Chain exists of: dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2 --> &htab->buckets[i].lock --> &head->lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&head->lock); local_irq_disable(); lock(dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2); lock(&htab->buckets[i].lock); <Interrupt> lock(dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2); *** DEADLOCK *** Fixes: e19494edab82 ("bpf: introduce percpu_freelist") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14bpf: improve verifier ARG_CONST_SIZE_OR_ZERO semanticsYonghong Song1-16/+24
For helpers, the argument type ARG_CONST_SIZE_OR_ZERO permits the access size to be 0 when accessing the previous argument (arg). Right now, it requires the arg needs to be NULL when size passed is 0 or could be 0. It also requires a non-NULL arg when the size is proved to be non-0. This patch changes verifier ARG_CONST_SIZE_OR_ZERO behavior such that for size-0 or possible size-0, it is not required the arg equal to NULL. There are a couple of reasons for this semantics change, and all of them intends to simplify user bpf programs which may improve user experience and/or increase chances of verifier acceptance. Together with the next patch which changes bpf_probe_read arg2 type from ARG_CONST_SIZE to ARG_CONST_SIZE_OR_ZERO, the following two examples, which fail the verifier currently, are able to get verifier acceptance. Example 1: unsigned long len = pend - pstart; len = len > MAX_PAYLOAD_LEN ? MAX_PAYLOAD_LEN : len; len &= MAX_PAYLOAD_LEN; bpf_probe_read(data->payload, len, pstart); It does not have test for "len > 0" and it failed the verifier. Users may not be aware that they have to add this test. Converting the bpf_probe_read helper to have ARG_CONST_SIZE_OR_ZERO helps the above code get verifier acceptance. Example 2: Here is one example where llvm "messed up" the code and the verifier fails. ...... unsigned long len = pend - pstart; if (len > 0 && len <= MAX_PAYLOAD_LEN) bpf_probe_read(data->payload, len, pstart); ...... The compiler generates the following code and verifier fails: ...... 39: (79) r2 = *(u64 *)(r10 -16) 40: (1f) r2 -= r8 41: (bf) r1 = r2 42: (07) r1 += -1 43: (25) if r1 > 0xffe goto pc+3 R0=inv(id=0) R1=inv(id=0,umax_value=4094,var_off=(0x0; 0xfff)) R2=inv(id=0) R6=map_value(id=0,off=0,ks=4,vs=4095,imm=0) R7=inv(id=0) R8=inv(id=0) R9=inv0 R10=fp0 44: (bf) r1 = r6 45: (bf) r3 = r8 46: (85) call bpf_probe_read#45 R2 min value is negative, either use unsigned or 'var &= const' ...... The compiler optimization is correct. If r1 = 0, r1 - 1 = 0xffffffffffffffff > 0xffe. If r1 != 0, r1 - 1 will not wrap. r1 > 0xffe at insn #43 can actually capture both "r1 > 0" and "len <= MAX_PAYLOAD_LEN". This however causes an issue in verifier as the value range of arg2 "r2" does not properly get refined and lead to verification failure. Relaxing bpf_prog_read arg2 from ARG_CONST_SIZE to ARG_CONST_SIZE_OR_ZERO allows the following simplied code: unsigned long len = pend - pstart; if (len <= MAX_PAYLOAD_LEN) bpf_probe_read(data->payload, len, pstart); The llvm compiler will generate less complex code and the verifier is able to verify that the program is okay. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11bpf: Revert bpf_overrid_function() helper changes.David S. Miller2-5/+0
NACK'd by x86 maintainer. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11bpf: add a bpf_override_function helperJosef Bacik2-0/+5
Error injection is sloppy and very ad-hoc. BPF could fill this niche perfectly with it's kprobe functionality. We could make sure errors are only triggered in specific call chains that we care about with very specific situations. Accomplish this with the bpf_override_funciton helper. This will modify the probe'd callers return value to the specified value and set the PC to an override function that simply returns, bypassing the originally probed function. This gives us a nice clean way to implement systematic error injection for all of our code paths. Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-07Merge branch 'linus' into perf/core, to fix conflictsIngo Molnar2-6/+24
Conflicts: tools/perf/arch/arm/annotate/instructions.c tools/perf/arch/arm64/annotate/instructions.c tools/perf/arch/powerpc/annotate/instructions.c tools/perf/arch/s390/annotate/instructions.c tools/perf/arch/x86/tests/intel-cqm.c tools/perf/ui/tui/progress.c tools/perf/util/zlib.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-05bpf, cgroup: implement eBPF-based device controller for cgroup v2Roman Gushchin3-0/+75
Cgroup v2 lacks the device controller, provided by cgroup v1. This patch adds a new eBPF program type, which in combination of previously added ability to attach multiple eBPF programs to a cgroup, will provide a similar functionality, but with some additional flexibility. This patch introduces a BPF_PROG_TYPE_CGROUP_DEVICE program type. A program takes major and minor device numbers, device type (block/character) and access type (mknod/read/write) as parameters and returns an integer which defines if the operation should be allowed or terminated with -EPERM. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05bpf: remove old offload/analyzerJakub Kicinski1-75/+0
Thanks to the ability to load a program for a specific device, running verifier twice is no longer needed. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05cls_bpf: allow attaching programs loaded for specific deviceJakub Kicinski1-0/+1
If TC program is loaded with skip_sw flag, we should allow the device-specific programs to be accepted. 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>
2017-11-05xdp: allow attaching programs loaded for specific deviceJakub Kicinski1-4/+29
Pass the netdev pointer to bpf_prog_get_type(). This way BPF code can decide whether the device matches what the code was loaded/translated for. 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: report offload info to user spaceJakub Kicinski2-0/+17
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 Kicinski5-8/+217
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>
2017-11-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03bpf: fix verifier NULL pointer dereferenceCraig Gallek1-4/+8
do_check() can fail early without allocating env->cur_state under memory pressure. Syzkaller found the stack below on the linux-next tree because of this. kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 27062 Comm: syz-executor5 Not tainted 4.14.0-rc7+ #106 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801c2c74700 task.stack: ffff8801c3e28000 RIP: 0010:free_verifier_state kernel/bpf/verifier.c:347 [inline] RIP: 0010:bpf_check+0xcf4/0x19c0 kernel/bpf/verifier.c:4533 RSP: 0018:ffff8801c3e2f5c8 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 00000000fffffff4 RCX: 0000000000000000 RDX: 0000000000000070 RSI: ffffffff817d5aa9 RDI: 0000000000000380 RBP: ffff8801c3e2f668 R08: 0000000000000000 R09: 1ffff100387c5d9f R10: 00000000218c4e80 R11: ffffffff85b34380 R12: ffff8801c4dc6a28 R13: 0000000000000000 R14: ffff8801c4dc6a00 R15: ffff8801c4dc6a20 FS: 00007f311079b700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004d4a24 CR3: 00000001cbcd0000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bpf_prog_load+0xcbb/0x18e0 kernel/bpf/syscall.c:1166 SYSC_bpf kernel/bpf/syscall.c:1690 [inline] SyS_bpf+0xae9/0x4620 kernel/bpf/syscall.c:1652 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x452869 RSP: 002b:00007f311079abe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452869 RDX: 0000000000000030 RSI: 0000000020168000 RDI: 0000000000000005 RBP: 00007f311079aa20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b7550 R13: 00007f311079ab58 R14: 00000000004b7560 R15: 0000000000000000 Code: df 48 c1 ea 03 80 3c 02 00 0f 85 e6 0b 00 00 4d 8b 6e 20 48 b8 00 00 00 00 00 fc ff df 49 8d bd 80 03 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 b6 0b 00 00 49 8b bd 80 03 00 00 e8 d6 0c 26 RIP: free_verifier_state kernel/bpf/verifier.c:347 [inline] RSP: ffff8801c3e2f5c8 RIP: bpf_check+0xcf4/0x19c0 kernel/bpf/verifier.c:4533 RSP: ffff8801c3e2f5c8 ---[ end trace c8d37f339dc64004 ]--- Fixes: 638f5b90d460 ("bpf: reduce verifier memory consumption") Fixes: 1969db47f8d0 ("bpf: fix verifier memory leaks") Signed-off-by: Craig Gallek <kraig@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03bpf: fix out-of-bounds access warning in bpf_checkArnd Bergmann1-0/+4
The bpf_verifer_ops array is generated dynamically and may be empty depending on configuration, which then causes an out of bounds access: kernel/bpf/verifier.c: In function 'bpf_check': kernel/bpf/verifier.c:4320:29: error: array subscript is above array bounds [-Werror=array-bounds] This adds a check to the start of the function as a workaround. I would assume that the function is never called in that configuration, so the warning is probably harmless. Fixes: 00176a34d9e2 ("bpf: remove the verifier ops from program structure") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03bpf: fix link error without CONFIG_NETArnd Bergmann1-0/+2
I ran into this link error with the latest net-next plus linux-next trees when networking is disabled: kernel/bpf/verifier.o:(.rodata+0x2958): undefined reference to `tc_cls_act_analyzer_ops' kernel/bpf/verifier.o:(.rodata+0x2970): undefined reference to `xdp_analyzer_ops' It seems that the code was written to deal with varying contents of the arrray, but the actual #ifdef was missing. Both tc_cls_act_analyzer_ops and xdp_analyzer_ops are defined in the core networking code, so adding a check for CONFIG_NET seems appropriate here, and I've verified this with many randconfig builds Fixes: 4f9218aaf8a4 ("bpf: move knowledge about post-translation offsets out of verifier") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02Merge tag 'spdx_identifiers-4.14-rc8' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull initial SPDX identifiers from Greg KH: "License cleanup: add SPDX license identifiers to some files Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: License cleanup: add SPDX license identifier to uapi header files with a license License cleanup: add SPDX license identifier to uapi header files with no license License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02bpf: also improve pattern matches for meta accessDaniel Borkmann1-69/+96
Follow-up to 0fd4759c5515 ("bpf: fix pattern matches for direct packet access") to cover also the remaining data_meta/data matches in the verifier. The matches are also refactored a bit to simplify handling of all the cases. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02bpf: minor cleanups after mergeDaniel Borkmann1-1/+1
Two minor cleanups after Dave's recent merge in f8ddadc4db6c ("Merge git://git.kernel.org...") of net into net-next in order to get the code in line with what was done originally in the net tree: i) use max() instead of max_t() since both ranges are u16, ii) don't split the direct access test cases in the middle with bpf_exit test cases from 390ee7e29fc ("bpf: enforce return code for cgroup-bpf programs"). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02bpf: cpumap micro-optimization in cpu_map_enqueueJesper Dangaard Brouer1-2/+2
Discovered that the compiler laid-out asm code in suboptimal way when studying perf report during benchmarking of cpumap. Help the compiler by the marking unlikely code paths. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+12
Smooth Cong Wang's bug fix into 'net-next'. Basically put the bulk of the tcf_block_put() logic from 'net' into tcf_block_put_ext(), but after the offload unbind. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01bpf: fix verifier memory leaksAlexei Starovoitov1-9/+18
fix verifier memory leaks Fixes: 638f5b90d460 ("bpf: reduce verifier memory consumption") Signed-off-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01bpf: remove SK_REDIRECT from UAPIJohn Fastabend1-4/+12
Now that SK_REDIRECT is no longer a valid return code. Remove it from the UAPI completely. Then do a namespace remapping internal to sockmap so SK_REDIRECT is no longer externally visible. Patchs primary change is to do a namechange from SK_REDIRECT to __SK_REDIRECT Reported-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01bpf: reduce verifier memory consumptionAlexei Starovoitov1-149/+288
the verifier got progressively smarter over time and size of its internal state grew as well. Time to reduce the memory consumption. Before: sizeof(struct bpf_verifier_state) = 6520 After: sizeof(struct bpf_verifier_state) = 896 It's done by observing that majority of BPF programs use little to no stack whereas verifier kept all of 512 stack slots ready always. Instead dynamically reallocate struct verifier state when stack access is detected. Runtime difference before vs after is within a noise. The number of processed instructions stays the same. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+10
Several conflicts here. NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to nfp_fl_output() needed some adjustments because the code block is in an else block now. Parallel additions to net/pkt_cls.h and net/sch_generic.h A bug fix in __tcp_retransmit_skb() conflicted with some of the rbtree changes in net-next. The tc action RCU callback fixes in 'net' had some overlap with some of the recent tcf_block reworking. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29bpf: rename sk_actions to align with bpf infrastructureJohn Fastabend1-1/+2
Recent additions to support multiple programs in cgroups impose a strict requirement, "all yes is yes, any no is no". To enforce this the infrastructure requires the 'no' return code, SK_DROP in this case, to be 0. To apply these rules to SK_SKB program types the sk_actions return codes need to be adjusted. This fix adds SK_PASS and makes 'SK_DROP = 0'. Finally, remove SK_ABORTED to remove any chance that the API may allow aborted program flows to be passed up the stack. This would be incorrect behavior and allow programs to break existing policies. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29bpf: bpf_compute_data uses incorrect cb structureJohn Fastabend1-2/+10
SK_SKB program types use bpf_compute_data to store the end of the packet data. However, bpf_compute_data assumes the cb is stored in the qdisc layer format. But, for SK_SKB this is the wrong layer of the stack for this type. It happens to work (sort of!) because in most cases nothing happens to be overwritten today. This is very fragile and error prone. Fortunately, we have another hole in tcp_skb_cb we can use so lets put the data_end value there. Note, SK_SKB program types do not use data_meta, they are failed by sk_skb_is_valid_access(). Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-27perf/bpf: Extend the perf_event_read_local() interface, a.k.a. "bpf: perf ↵Yonghong Song1-1/+1
event change needed for subsequent bpf helpers" eBPF programs would like access to the (perf) event enabled and running times along with the event value, such that they can deal with event multiplexing (among other things). This patch extends the interface; a future eBPF patch will utilize the new functionality. [ Note, there's a same-content commit with a poor changelog and a meaningless title in the networking tree as well - but we need this change for subsequent perf work, so apply it here as well, with a proper changelog. Hopefully Git will be able to sort out this somewhat messy workflow, if there are no other, conflicting changes to these files. ] Signed-off-by: Yonghong Song <yhs@fb.com> [ Rewrote the changelog. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <ast@fb.com> Cc: <daniel@iogearbox.net> Cc: <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20171005161923.332790-2-yhs@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25bpf: permit multiple bpf attachments for a single perf eventYonghong Song1-0/+81
This patch enables multiple bpf attachments for a kprobe/uprobe/tracepoint single trace event. Each trace_event keeps a list of attached perf events. When an event happens, all attached bpf programs will be executed based on the order of attachment. A global bpf_event_mutex lock is introduced to protect prog_array attaching and detaching. An alternative will be introduce a mutex lock in every trace_event_call structure, but it takes a lot of extra memory. So a global bpf_event_mutex lock is a good compromise. The bpf prog detachment involves allocation of memory. If the allocation fails, a dummy do-nothing program will replace to-be-detached program in-place. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-24bpf: cpumap fix potential lost wake-up problemJesper Dangaard Brouer1-4/+8
As pointed out by Michael, commit 1c601d829ab0 ("bpf: cpumap xdp_buff to skb conversion and allocation") contains a classical example of the potential lost wake-up problem. We need to recheck the condition __ptr_ring_empty() after changing current->state to TASK_INTERRUPTIBLE, this avoids a race between wake_up_process() and schedule(). After this, a race with wake_up_process() will simply change the state to TASK_RUNNING, and the schedule() call not really put us to sleep. Fixes: 1c601d829ab0 ("bpf: cpumap xdp_buff to skb conversion and allocation") Reported-by: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller5-36/+90
There were quite a few overlapping sets of changes here. Daniel's bug fix for off-by-ones in the new BPF branch instructions, along with the added allowances for "data_end > ptr + x" forms collided with the metadata additions. Along with those three changes came veritifer test cases, which in their final form I tried to group together properly. If I had just trimmed GIT's conflict tags as-is, this would have split up the meta tests unnecessarily. In the socketmap code, a set of preemption disabling changes overlapped with the rename of bpf_compute_data_end() to bpf_compute_data_pointers(). Changes were made to the mv88e6060.c driver set addr method which got removed in net-next. The hyperv transport socket layer had a locking change in 'net' which overlapped with a change of socket state macro usage in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22bpf: fix pattern matches for direct packet accessDaniel Borkmann1-0/+24
Alexander had a test program with direct packet access, where the access test was in the form of data + X > data_end. In an unrelated change to the program LLVM decided to swap the branches and emitted code for the test in form of data + X <= data_end. We hadn't seen these being generated previously, thus verifier would reject the program. Therefore, fix up the verifier to detect all test cases, so we don't run into such issues in the future. Fixes: b4e432f1000a ("bpf: enable BPF_J{LT, LE, SLT, SLE} opcodes in verifier") Reported-by: Alexander Alemayhu <alexander@alemayhu.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22bpf: fix off by one for range markings with L{T, E} patternsDaniel Borkmann1-12/+21
During review I noticed that the current logic for direct packet access marking in check_cond_jmp_op() has an off by one for the upper right range border when marking in find_good_pkt_pointers() with BPF_JLT and BPF_JLE. It's not really harmful given access up to pkt_end is always safe, but we should nevertheless correct the range marking before it becomes ABI. If pkt_data' denotes a pkt_data derived pointer (pkt_data + X), then for pkt_data' < pkt_end in the true branch as well as for pkt_end <= pkt_data' in the false branch we mark the range with X although it should really be X - 1 in these cases. For example, X could be pkt_end - pkt_data, then when testing for pkt_data' < pkt_end the verifier simulation cannot deduce that a byte load of pkt_data' - 1 would succeed in this branch. Fixes: b4e432f1000a ("bpf: enable BPF_J{LT, LE, SLT, SLE} opcodes in verifier") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22bpf: devmap fix arithmetic overflow in bitmap_size calculationJohn Fastabend1-1/+1
An integer overflow is possible in dev_map_bitmap_size() when calculating the BITS_TO_LONG logic which becomes, after macro replacement, (((n) + (d) - 1)/ (d)) where 'n' is a __u32 and 'd' is (8 * sizeof(long)). To avoid overflow cast to u64 before arithmetic. Reported-by: Richard Weinberger <richard@nod.at> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20selinux: bpf: Add addtional check for bpf object file receiveChenbo Feng1-2/+2
Introduce a bpf object related check when sending and receiving files through unix domain socket as well as binder. It checks if the receiving process have privilege to read/write the bpf map or use the bpf program. This check is necessary because the bpf maps and programs are using a anonymous inode as their shared inode so the normal way of checking the files and sockets when passing between processes cannot work properly on eBPF object. This check only works when the BPF_SYSCALL is configured. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20security: bpf: Add LSM hooks for bpf object related syscallChenbo Feng1-2/+32
Introduce several LSM hooks for the syscalls that will allow the userspace to access to eBPF object such as eBPF programs and eBPF maps. The security check is aimed to enforce a per object security protection for eBPF object so only processes with the right priviliges can read/write to a specific map or use a specific eBPF program. Besides that, a general security hook is added before the multiplexer of bpf syscall to check the cmd and the attribute used for the command. The actual security module can decide which command need to be checked and how the cmd should be checked. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20bpf: Add file mode configuration into bpf mapsChenbo Feng8-22/+110
Introduce the map read/write flags to the eBPF syscalls that returns the map fd. The flags is used to set up the file mode when construct a new file descriptor for bpf maps. To not break the backward capability, the f_flags is set to O_RDWR if the flag passed by syscall is 0. Otherwise it should be O_RDONLY or O_WRONLY. When the userspace want to modify or read the map content, it will check the file mode to see if it is allowed to make the change. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>