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2018-10-19bpf: rename stack trace map operationsMauricio Vasquez B
In the following patches queue and stack maps (FIFO and LIFO datastructures) will be implemented. In order to avoid confusion and a possible name clash rename stack_map_ops to stack_trace_map_ops Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
net/sched/cls_api.c has overlapping changes to a call to nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL to the 5th argument, and another (from 'net-next') added cb->extack instead of NULL to the 6th argument. net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to code which moved (to mr_table_dump)) in 'net-next'. Thanks to David Ahern for the heads up. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15bpf, sockmap: convert to generic sk_msg interfaceDaniel Borkmann
Add a generic sk_msg layer, and convert current sockmap and later kTLS over to make use of it. While sk_buff handles network packet representation from netdevice up to socket, sk_msg handles data representation from application to socket layer. This means that sk_msg framework spans across ULP users in the kernel, and enables features such as introspection or filtering of data with the help of BPF programs that operate on this data structure. Latter becomes in particular useful for kTLS where data encryption is deferred into the kernel, and as such enabling the kernel to perform L7 introspection and policy based on BPF for TLS connections where the record is being encrypted after BPF has run and came to a verdict. In order to get there, first step is to transform open coding of scatter-gather list handling into a common core framework that subsystems can use. The code itself has been split and refactored into three bigger pieces: i) the generic sk_msg API which deals with managing the scatter gather ring, providing helpers for walking and mangling, transferring application data from user space into it, and preparing it for BPF pre/post-processing, ii) the plain sock map itself where sockets can be attached to or detached from; these bits are independent of i) which can now be used also without sock map, and iii) the integration with plain TCP as one protocol to be used for processing L7 application data (later this could e.g. also be extended to other protocols like UDP). The semantics are the same with the old sock map code and therefore no change of user facing behavior or APIs. While pursuing this work it also helped finding a number of bugs in the old sockmap code that we've fixed already in earlier commits. The test_sockmap kselftest suite passes through fine as well. Joint work with John. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15tcp, ulp: remove ulp bits from sockmapDaniel Borkmann
In order to prepare sockmap logic to be used in combination with kTLS we need to detangle it from ULP, and further split it in later commits into a generic API. Joint work with John. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12bpf: wait for running BPF programs when updating map-in-mapDaniel Colascione
The map-in-map frequently serves as a mechanism for atomic snapshotting of state that a BPF program might record. The current implementation is dangerous to use in this way, however, since userspace has no way of knowing when all programs that might have retrieved the "old" value of the map may have completed. This change ensures that map update operations on map-in-map map types always wait for all references to the old map to drop before returning to userspace. Signed-off-by: Daniel Colascione <dancol@google.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-11xsk: do not call synchronize_net() under RCU read lockBjörn Töpel
The XSKMAP update and delete functions called synchronize_net(), which can sleep. It is not allowed to sleep during an RCU read section. Instead we need to make sure that the sock sk_destruct (xsk_destruct) function is asynchronously called after an RCU grace period. Setting the SOCK_RCU_FREE flag for XDP sockets takes care of this. Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-09bpf: return EOPNOTSUPP when map lookup isn't supportedPrashant Bhole
Return ERR_PTR(-EOPNOTSUPP) from map_lookup_elem() methods of below map types: - BPF_MAP_TYPE_PROG_ARRAY - BPF_MAP_TYPE_STACK_TRACE - BPF_MAP_TYPE_XSKMAP - BPF_MAP_TYPE_SOCKMAP/BPF_MAP_TYPE_SOCKHASH Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09bpf: error handling when map_lookup_elem isn't supportedPrashant Bhole
The error value returned by map_lookup_elem doesn't differentiate whether lookup was failed because of invalid key or lookup is not supported. Lets add handling for -EOPNOTSUPP return value of map_lookup_elem() method of map, with expectation from map's implementation that it should return -EOPNOTSUPP if lookup is not supported. The errno for bpf syscall for BPF_MAP_LOOKUP_ELEM command will be set to EOPNOTSUPP if map lookup is not supported. Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09bpf: btf: Fix a missing check bugWenwen Wang
In btf_parse_hdr(), the length of the btf data header is firstly copied from the user space to 'hdr_len' and checked to see whether it is larger than 'btf_data_size'. If yes, an error code EINVAL is returned. Otherwise, the whole header is copied again from the user space to 'btf->hdr'. However, after the second copy, there is no check between 'btf->hdr->hdr_len' and 'hdr_len' to confirm that the two copies get the same value. Given that the btf data is in the user space, a malicious user can race to change the data between the two copies. By doing so, the user can provide malicious data to the kernel and cause undefined behavior. This patch adds a necessary check after the second copy, to make sure 'btf->hdr->hdr_len' has the same value as 'hdr_len'. Otherwise, an error code EINVAL will be returned. Signed-off-by: Wenwen Wang <wang6495@umn.edu> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2018-10-08 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) sk_lookup_[tcp|udp] and sk_release helpers from Joe Stringer which allow BPF programs to perform lookups for sockets in a network namespace. This would allow programs to determine early on in processing whether the stack is expecting to receive the packet, and perform some action (eg drop, forward somewhere) based on this information. 2) per-cpu cgroup local storage from Roman Gushchin. Per-cpu cgroup local storage is very similar to simple cgroup storage except all the data is per-cpu. The main goal of per-cpu variant is to implement super fast counters (e.g. packet counters), which don't require neither lookups, neither atomic operations in a fast path. The example of these hybrid counters is in selftests/bpf/netcnt_prog.c 3) allow HW offload of programs with BPF-to-BPF function calls from Quentin Monnet 4) support more than 64-byte key/value in HW offloaded BPF maps from Jakub Kicinski 5) rename of libbpf interfaces from Andrey Ignatov. libbpf is maturing as a library and should follow good practices in library design and implementation to play well with other libraries. This patch set brings consistent naming convention to global symbols. 6) relicense libbpf as LGPL-2.1 OR BSD-2-Clause from Alexei Starovoitov to let Apache2 projects use libbpf 7) various AF_XDP fixes from Björn and Magnus ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08bpf: allow offload of programs with BPF-to-BPF function callsQuentin Monnet
Now that there is at least one driver supporting BPF-to-BPF function calls, lift the restriction, in the verifier, on hardware offload of eBPF programs containing such calls. But prevent jit_subprogs(), still in the verifier, from being run for offloaded programs. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08bpf: add verifier callback to get stack usage info for offloaded progsQuentin Monnet
In preparation for BPF-to-BPF calls in offloaded programs, add a new function attribute to the struct bpf_prog_offload_ops so that drivers supporting eBPF offload can hook at the end of program verification, and potentially extract information collected by the verifier. Implement a minimal callback (returning 0) in the drivers providing the structs, namely netdevsim and nfp. This will be useful in the nfp driver, in later commits, to extract the number of subprograms as well as the stack depth for those subprograms. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-10-05bpf: 32-bit RSH verification must truncate input before the ALU opJann Horn
When I wrote commit 468f6eafa6c4 ("bpf: fix 32-bit ALU op verification"), I assumed that, in order to emulate 64-bit arithmetic with 32-bit logic, it is sufficient to just truncate the output to 32 bits; and so I just moved the register size coercion that used to be at the start of the function to the end of the function. That assumption is true for almost every op, but not for 32-bit right shifts, because those can propagate information towards the least significant bit. Fix it by always truncating inputs for 32-bit ops to 32 bits. Also get rid of the coerce_reg_to_size() after the ALU op, since that has no effect. Fixes: 468f6eafa6c4 ("bpf: fix 32-bit ALU op verification") Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Add helper to retrieve socket in BPFJoe Stringer
This patch adds new BPF helper functions, bpf_sk_lookup_tcp() and bpf_sk_lookup_udp() which allows BPF programs to find out if there is a socket listening on this host, and returns a socket pointer which the BPF program can then access to determine, for instance, whether to forward or drop traffic. bpf_sk_lookup_xxx() may take a reference on the socket, so when a BPF program makes use of this function, it must subsequently pass the returned pointer into the newly added sk_release() to return the reference. By way of example, the following pseudocode would filter inbound connections at XDP if there is no corresponding service listening for the traffic: struct bpf_sock_tuple tuple; struct bpf_sock_ops *sk; populate_tuple(ctx, &tuple); // Extract the 5tuple from the packet sk = bpf_sk_lookup_tcp(ctx, &tuple, sizeof tuple, netns, 0); if (!sk) { // Couldn't find a socket listening for this traffic. Drop. return TC_ACT_SHOT; } bpf_sk_release(sk, 0); return TC_ACT_OK; Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Add reference tracking to verifierJoe Stringer
Allow helper functions to acquire a reference and return it into a register. Specific pointer types such as the PTR_TO_SOCKET will implicitly represent such a reference. The verifier must ensure that these references are released exactly once in each path through the program. To achieve this, this commit assigns an id to the pointer and tracks it in the 'bpf_func_state', then when the function or program exits, verifies that all of the acquired references have been freed. When the pointer is passed to a function that frees the reference, it is removed from the 'bpf_func_state` and all existing copies of the pointer in registers are marked invalid. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Macrofy stack state copyJoe Stringer
An upcoming commit will need very similar copy/realloc boilerplate, so refactor the existing stack copy/realloc functions into macros to simplify it. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Add PTR_TO_SOCKET verifier typeJoe Stringer
Teach the verifier a little bit about a new type of pointer, a PTR_TO_SOCKET. This pointer type is accessed from BPF through the 'struct bpf_sock' structure. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Generalize ptr_or_null regs checkJoe Stringer
This check will be reused by an upcoming commit for conditional jump checks for sockets. Refactor it a bit to simplify the later commit. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Reuse canonical string formatter for ctx errsJoe Stringer
The array "reg_type_str" provides canonical formatting of register types, however a couple of places would previously check whether a register represented the context and write the name "context" directly. An upcoming commit will add another pointer type to these statements, so to provide more accurate error messages in the verifier, update these error messages to use "reg_type_str" instead. Signed-off-by: Joe Stringer <joe@wand.net.nz> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Simplify ptr_min_max_vals adjustmentJoe Stringer
An upcoming commit will add another two pointer types that need very similar behaviour, so generalise this function now. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03bpf: Add iterator for spilled registersJoe Stringer
Add this iterator for spilled registers, it concentrates the details of how to get the current frame's spilled registers into a single macro while clarifying the intention of the code which is calling the macro. Signed-off-by: Joe Stringer <joe@wand.net.nz> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02bpf: don't accept cgroup local storage with zero value sizeRoman Gushchin
Explicitly forbid creating cgroup local storage maps with zero value size, as it makes no sense and might even cause a panic. Reported-by: syzbot+18628320d3b14a5c459c@syzkaller.appspotmail.com Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01bpf: don't allow create maps of per-cpu cgroup local storagesRoman Gushchin
Explicitly forbid creating map of per-cpu cgroup local storages. This behavior matches the behavior of shared cgroup storages. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01bpf: introduce per-cpu cgroup local storageRoman Gushchin
This commit introduced per-cpu cgroup local storage. Per-cpu cgroup local storage is very similar to simple cgroup storage (let's call it shared), except all the data is per-cpu. The main goal of per-cpu variant is to implement super fast counters (e.g. packet counters), which don't require neither lookups, neither atomic operations. >From userspace's point of view, accessing a per-cpu cgroup storage is similar to other per-cpu map types (e.g. per-cpu hashmaps and arrays). Writing to a per-cpu cgroup storage is not atomic, but is performed by copying longs, so some minimal atomicity is here, exactly as with other per-cpu maps. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01bpf: rework cgroup storage pointer passingRoman Gushchin
To simplify the following introduction of per-cpu cgroup storage, let's rework a bit a mechanism of passing a pointer to a cgroup storage into the bpf_get_local_storage(). Let's save a pointer to the corresponding bpf_cgroup_storage structure, instead of a pointer to the actual buffer. It will help us to handle per-cpu storage later, which has a different way of accessing to the actual data. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01bpf: extend cgroup bpf core to allow multiple cgroup storage typesRoman Gushchin
In order to introduce per-cpu cgroup storage, let's generalize bpf cgroup core to support multiple cgroup storage types. Potentially, per-node cgroup storage can be added later. This commit is mostly a formal change that replaces cgroup_storage pointer with a array of cgroup_storage pointers. It doesn't actually introduce a new storage type, it will be done later. Each bpf program is now able to have one cgroup storage of each type. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-28bpf: harden flags check in cgroup_storage_update_elem()Roman Gushchin
cgroup_storage_update_elem() shouldn't accept any flags argument values except BPF_ANY and BPF_EXIST to guarantee the backward compatibility, had a new flag value been added. Fixes: de9cbbaadba5 ("bpf: introduce cgroup storage maps") Signed-off-by: Roman Gushchin <guro@fb.com> Reported-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-28bpf: permit CGROUP_DEVICE programs accessing helper bpf_get_current_cgroup_id()Yonghong Song
Currently, helper bpf_get_current_cgroup_id() is not permitted for CGROUP_DEVICE type of programs. If the helper is used in such cases, the verifier will log the following error: 0: (bf) r6 = r1 1: (69) r7 = *(u16 *)(r6 +0) 2: (85) call bpf_get_current_cgroup_id#80 unknown func bpf_get_current_cgroup_id#80 The bpf_get_current_cgroup_id() is useful for CGROUP_DEVICE type of programs in order to customize action based on cgroup id. This patch added such a support. Cc: Roman Gushchin <guro@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-09-25 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Allow for RX stack hardening by implementing the kernel's flow dissector in BPF. Idea was originally presented at netconf 2017 [0]. Quote from merge commit: [...] Because of the rigorous checks of the BPF verifier, this provides significant security guarantees. In particular, the BPF flow dissector cannot get inside of an infinite loop, as with CVE-2013-4348, because BPF programs are guaranteed to terminate. It cannot read outside of packet bounds, because all memory accesses are checked. Also, with BPF the administrator can decide which protocols to support, reducing potential attack surface. Rarely encountered protocols can be excluded from dissection and the program can be updated without kernel recompile or reboot if a bug is discovered. [...] Also, a sample flow dissector has been implemented in BPF as part of this work, from Petar and Willem. [0] http://vger.kernel.org/netconf2017_files/rx_hardening_and_udp_gso.pdf 2) Add support for bpftool to list currently active attachment points of BPF networking programs providing a quick overview similar to bpftool's perf subcommand, from Yonghong. 3) Fix a verifier pruning instability bug where a union member from the register state was not cleared properly leading to branches not being pruned despite them being valid candidates, from Alexei. 4) Various smaller fast-path optimizations in XDP's map redirect code, from Jesper. 5) Enable to recognize BPF_MAP_TYPE_REUSEPORT_SOCKARRAY maps in bpftool, from Roman. 6) Remove a duplicate check in libbpf that probes for function storage, from Taeung. 7) Fix an issue in test_progs by avoid checking for errno since on success its value should not be checked, from Mauricio. 8) Fix unused variable warning in bpf_getsockopt() helper when CONFIG_INET is not configured, from Anders. 9) Fix a compilation failure in the BPF sample code's use of bpf_flow_keys, from Prashant. 10) Minor cleanups in BPF code, from Yue and Zhong. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Version bump conflict in batman-adv, take what's in net-next. iavf conflict, adjustment of netdev_ops in net-next conflicting with poll controller method removal in net. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-22bpf: sockmap, fix transition through disconnect without closeJohn Fastabend
It is possible (via shutdown()) for TCP socks to go trough TCP_CLOSE state via tcp_disconnect() without actually calling tcp_close which would then call our bpf_tcp_close() callback. Because of this a user could disconnect a socket then put it in a LISTEN state which would break our assumptions about sockets always being ESTABLISHED state. To resolve this rely on the unhash hook, which is called in the disconnect case, to remove the sock from the sockmap. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-22bpf: sockmap only allow ESTABLISHED sock stateJohn Fastabend
After this patch we only allow socks that are in ESTABLISHED state or are being added via a sock_ops event that is transitioning into an ESTABLISHED state. By allowing sock_ops events we allow users to manage sockmaps directly from sock ops programs. The two supported sock_ops ops are BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB and BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB. Similar to TLS ULP this ensures sk_user_data is correct. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-21bpf: remove redundant null pointer check before consume_skbzhong jiang
consume_skb has taken the null pointer into account. hence it is safe to remove the redundant null pointer check before consume_skb. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-18Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Two new tls tests added in parallel in both net and net-next. Used Stephen Rothwell's linux-next resolution. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-14flow_dissector: implements flow dissector BPF hookPetar Penkov
Adds a hook for programs of type BPF_PROG_TYPE_FLOW_DISSECTOR and attach type BPF_FLOW_DISSECTOR that is executed in the flow dissector path. The BPF program is per-network namespace. Signed-off-by: Petar Penkov <ppenkov@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-12bpf/verifier: disallow pointer subtractionAlexei Starovoitov
Subtraction of pointers was accidentally allowed for unpriv programs by commit 82abbf8d2fc4. Revert that part of commit. Fixes: 82abbf8d2fc4 ("bpf: do not allow root to mangle valid pointers") Reported-by: Jann Horn <jannh@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-12bpf: btf: Fix end boundary calculation for type sectionMartin KaFai Lau
The end boundary math for type section is incorrect in btf_check_all_metas(). It just happens that hdr->type_off is always 0 for now because there are only two sections (type and string) and string section must be at the end (ensured in btf_parse_str_sec). However, type_off may not be 0 if a new section would be added later. This patch fixes it. Fixes: f80442a4cd18 ("bpf: btf: Change how section is supported in btf_header") Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-11bpf: add bpffs pretty print for program array mapYonghong Song
Added bpffs pretty print for program array map. For a particular array index, if the program array points to a valid program, the "<index>: <prog_id>" will be printed out like 0: 6 which means bpf program with id "6" is installed at index "0". Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-05bpf/verifier: fix verifier instabilityAlexei Starovoitov
Edward Cree says: In check_mem_access(), for the PTR_TO_CTX case, after check_ctx_access() has supplied a reg_type, the other members of the register state are set appropriately. Previously reg.range was set to 0, but as it is in a union with reg.map_ptr, which is larger, upper bytes of the latter were left in place. This then caused the memcmp() in regsafe() to fail, preventing some branches from being pruned (and occasionally causing the same program to take a varying number of processed insns on repeated verifier runs). Fix the instability by clearing bpf_reg_state in __mark_reg_[un]known() Fixes: f1174f77b50c ("bpf/verifier: rework value tracking") Debugged-by: Edward Cree <ecree@solarflare.com> Acked-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-09-02bpf: avoid misuse of psock when TCP_ULP_BPF collides with another ULPJohn Fastabend
Currently we check sk_user_data is non NULL to determine if the sk exists in a map. However, this is not sufficient to ensure the psock or the ULP ops are not in use by another user, such as kcm or TLS. To avoid this when adding a sock to a map also verify it is of the correct ULP type. Additionally, when releasing a psock verify that it is the TCP_ULP_BPF type before releasing the ULP. The error case where we abort an update due to ULP collision can cause this error path. For example, __sock_map_ctx_update_elem() [...] err = tcp_set_ulp_id(sock, TCP_ULP_BPF) <- collides with TLS if (err) <- so err out here goto out_free [...] out_free: smap_release_sock() <- calling tcp_cleanup_ulp releases the TLS ULP incorrectly. Fixes: 2f857d04601a ("bpf: sockmap, remove STRPARSER map_flags and add multi-map support") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-30bpf: add bpffs pretty print for percpu arraymap/hash/lru_hashYonghong Song
Added bpffs pretty print for percpu arraymap, percpu hashmap and percpu lru hashmap. For each map <key, value> pair, the format is: <key_value>: { cpu0: <value_on_cpu0> cpu1: <value_on_cpu1> ... cpun: <value_on_cpun> } For example, on my VM, there are 4 cpus, and for test_btf test in the next patch: cat /sys/fs/bpf/pprint_test_percpu_hash You may get: ... 43602: { cpu0: {43602,0,-43602,0x3,0xaa52,0x3,{43602|[82,170,0,0,0,0,0,0]},ENUM_TWO} cpu1: {43602,0,-43602,0x3,0xaa52,0x3,{43602|[82,170,0,0,0,0,0,0]},ENUM_TWO} cpu2: {43602,0,-43602,0x3,0xaa52,0x3,{43602|[82,170,0,0,0,0,0,0]},ENUM_TWO} cpu3: {43602,0,-43602,0x3,0xaa52,0x3,{43602|[82,170,0,0,0,0,0,0]},ENUM_TWO} } 72847: { cpu0: {72847,0,-72847,0x3,0x11c8f,0x3,{72847|[143,28,1,0,0,0,0,0]},ENUM_THREE} cpu1: {72847,0,-72847,0x3,0x11c8f,0x3,{72847|[143,28,1,0,0,0,0,0]},ENUM_THREE} cpu2: {72847,0,-72847,0x3,0x11c8f,0x3,{72847|[143,28,1,0,0,0,0,0]},ENUM_THREE} cpu3: {72847,0,-72847,0x3,0x11c8f,0x3,{72847|[143,28,1,0,0,0,0,0]},ENUM_THREE} } ... Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-29bpf/verifier: display non-spill stack slot types in print_verifier_stateEdward Cree
If a stack slot does not hold a spilled register (STACK_SPILL), then each of its eight bytes could potentially have a different slot_type. This information can be important for debugging, and previously we either did not print anything for the stack slot, or just printed fp-X=0 in the case where its first byte was STACK_ZERO. Instead, print eight characters with either 0 (STACK_ZERO), m (STACK_MISC) or ? (STACK_INVALID) for any stack slot which is neither STACK_SPILL nor entirely STACK_INVALID. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29bpf/verifier: per-register parent pointersEdward Cree
By giving each register its own liveness chain, we elide the skip_callee() logic. Instead, each register's parent is the state it inherits from; both check_func_call() and prepare_func_exit() automatically connect reg states to the correct chain since when they copy the reg state across (r1-r5 into the callee as args, and r0 out as the return value) they also copy the parent pointer. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-29bpf: remove duplicated include from syscall.cYueHaibing
Remove duplicated include. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-28bpf: sockmap, decrement copied count correctly in redirect error caseJohn Fastabend
Currently, when a redirect occurs in sockmap and an error occurs in the redirect call we unwind the scatterlist once in the error path of bpf_tcp_sendmsg_do_redirect() and then again in sendmsg(). Then in the error path of sendmsg we decrement the copied count by the send size. However, its possible we partially sent data before the error was generated. This can happen if do_tcp_sendpages() partially sends the scatterlist before encountering a memory pressure error. If this happens we need to decrement the copied value (the value tracking how many bytes were actually sent to TCP stack) by the number of remaining bytes _not_ the entire send size. Otherwise we risk confusing userspace. Also we don't need two calls to free the scatterlist one is good enough. So remove the one in bpf_tcp_sendmsg_do_redirect() and then properly reduce copied by the number of remaining bytes which may in fact be the entire send size if no bytes were sent. To do this use bool to indicate if free_start_sg() should do mem accounting or not. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-27bpf, sockmap: fix psock refcount leak in bpf_tcp_recvmsgDaniel Borkmann
In bpf_tcp_recvmsg() we first took a reference on the psock, however once we find that there are skbs in the normal socket's receive queue we return with processing them through tcp_recvmsg(). Problem is that we leak the taken reference on the psock in that path. Given we don't really do anything with the psock at this point, move the skb_queue_empty() test before we fetch the psock to fix this case. Fixes: 8934ce2fd081 ("bpf: sockmap redirect ingress support") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-27bpf, sockmap: fix potential use after free in bpf_tcp_closeDaniel Borkmann
bpf_tcp_close() we pop the psock linkage to a map via psock_map_pop(). A parallel update on the sock hash map can happen between psock_map_pop() and lookup_elem_raw() where we override the element under link->hash / link->key. In bpf_tcp_close()'s lookup_elem_raw() we subsequently only test whether an element is present, but we do not test whether the element is infact the element we were looking for. We lock the sock in bpf_tcp_close() during that time, so do we hold the lock in sock_hash_update_elem(). However, the latter locks the sock which is newly updated, not the one we're purging from the hash table. This means that while one CPU is doing the lookup from bpf_tcp_close(), another CPU is doing the map update in parallel, dropped our sock from the hlist and released the psock. Subsequently the first CPU will find the new sock and attempts to drop and release the old sock yet another time. Fix is that we need to check the elements for a match after lookup, similar as we do in the sock map. Note that the hash tab elems are freed via RCU, so access to their link->hash / link->key is fine since we're under RCU read side there. Fixes: e9db4ef6bf4c ("bpf: sockhash fix omitted bucket lock in sock_close") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-23bpf: use per htab salt for bucket hashDaniel Borkmann
All BPF hash and LRU maps currently have a known and global seed we feed into jhash() which is 0. This is suboptimal, thus fix it by generating a random seed upon hashtab setup time which we can later on feed into jhash() on lookup, update and deletions. Fixes: 0f8e4bd8a1fc8 ("bpf: add hashtable type of eBPF maps") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Reviewed-by: Eduardo Valentin <eduval@amazon.com>