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2018-08-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller14-25/+478
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-08-13 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add driver XDP support for veth. This can be used in conjunction with redirect of another XDP program e.g. sitting on NIC so the xdp_frame can be forwarded to the peer veth directly without modification, from Toshiaki. 2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT in order to provide more control and visibility on where a SO_REUSEPORT sk should be located, and the latter enables to directly select a sk from the bpf map. This also enables map-in-map for application migration use cases, from Martin. 3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id of cgroup v2 that is the ancestor of the cgroup associated with the skb at the ancestor_level, from Andrey. 4) Implement BPF fs map pretty-print support based on BTF data for regular hash table and LRU map, from Yonghong. 5) Decouple the ability to attach BTF for a map from the key and value pretty-printer in BPF fs, and enable further support of BTF for maps for percpu and LPM trie, from Daniel. 6) Implement a better BPF sample of using XDP's CPU redirect feature for load balancing SKB processing to remote CPU. The sample implements the same XDP load balancing as Suricata does which is symmetric hash based on IP and L4 protocol, from Jesper. 7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s critical path as it is ensured that the allocator is present, from Björn. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-13bpf: decouple btf from seq bpf fs dump and enable more mapsDaniel Borkmann11-40/+66
Commit a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap") and 699c86d6ec21 ("bpf: btf: add pretty print for hash/lru_hash maps") enabled support for BTF and dumping via BPF fs for array and hash/lru map. However, both can be decoupled from each other such that regular BPF maps can be supported for attaching BTF key/value information, while not all maps necessarily need to dump via map_seq_show_elem() callback. The basic sanity check which is a prerequisite for all maps is that key/value size has to match in any case, and some maps can have extra checks via map_check_btf() callback, e.g. probing certain types or indicating no support in general. With that we can also enable retrieving BTF info for per-cpu map types and lpm. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com>
2018-08-11Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-14/+24
2018-08-11bpf: Introduce BPF_PROG_TYPE_SK_REUSEPORTMartin KaFai Lau1-0/+9
This patch adds a BPF_PROG_TYPE_SK_REUSEPORT which can select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY. Like other non SK_FILTER/CGROUP_SKB program, it requires CAP_SYS_ADMIN. BPF_PROG_TYPE_SK_REUSEPORT introduces "struct sk_reuseport_kern" to store the bpf context instead of using the skb->cb[48]. At the SO_REUSEPORT sk lookup time, it is in the middle of transiting from a lower layer (ipv4/ipv6) to a upper layer (udp/tcp). At this point, it is not always clear where the bpf context can be appended in the skb->cb[48] to avoid saving-and-restoring cb[]. Even putting aside the difference between ipv4-vs-ipv6 and udp-vs-tcp. It is not clear if the lower layer is only ipv4 and ipv6 in the future and will it not touch the cb[] again before transiting to the upper layer. For example, in udp_gro_receive(), it uses the 48 byte NAPI_GRO_CB instead of IP[6]CB and it may still modify the cb[] after calling the udp[46]_lib_lookup_skb(). Because of the above reason, if sk->cb is used for the bpf ctx, saving-and-restoring is needed and likely the whole 48 bytes cb[] has to be saved and restored. Instead of saving, setting and restoring the cb[], this patch opts to create a new "struct sk_reuseport_kern" and setting the needed values in there. The new BPF_PROG_TYPE_SK_REUSEPORT and "struct sk_reuseport_(kern|md)" will serve all ipv4/ipv6 + udp/tcp combinations. There is no protocol specific usage at this point and it is also inline with the current sock_reuseport.c implementation (i.e. no protocol specific requirement). In "struct sk_reuseport_md", this patch exposes data/data_end/len with semantic similar to other existing usages. Together with "bpf_skb_load_bytes()" and "bpf_skb_load_bytes_relative()", the bpf prog can peek anywhere in the skb. The "bind_inany" tells the bpf prog that the reuseport group is bind-ed to a local INANY address which cannot be learned from skb. The new "bind_inany" is added to "struct sock_reuseport" which will be used when running the new "BPF_PROG_TYPE_SK_REUSEPORT" bpf prog in order to avoid repeating the "bind INANY" test on "sk_v6_rcv_saddr/sk->sk_rcv_saddr" every time a bpf prog is run. It can only be properly initialized when a "sk->sk_reuseport" enabled sk is adding to a hashtable (i.e. during "reuseport_alloc()" and "reuseport_add_sock()"). The new "sk_select_reuseport()" is the main helper that the bpf prog will use to select a SO_REUSEPORT sk. It is the only function that can use the new BPF_MAP_TYPE_REUSEPORT_ARRAY. As mentioned in the earlier patch, the validity of a selected sk is checked in run time in "sk_select_reuseport()". Doing the check in verification time is difficult and inflexible (consider the map-in-map use case). The runtime check is to compare the selected sk's reuseport_id with the reuseport_id that we want. This helper will return -EXXX if the selected sk cannot serve the incoming request (e.g. reuseport_id not match). The bpf prog can decide if it wants to do SK_DROP as its discretion. When the bpf prog returns SK_PASS, the kernel will check if a valid sk has been selected (i.e. "reuse_kern->selected_sk != NULL"). If it does , it will use the selected sk. If not, the kernel will select one from "reuse->socks[]" (as before this patch). The SK_DROP and SK_PASS handling logic will be in the next patch. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-11bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAYMartin KaFai Lau4-1/+373
This patch introduces a new map type BPF_MAP_TYPE_REUSEPORT_SOCKARRAY. To unleash the full potential of a bpf prog, it is essential for the userspace to be capable of directly setting up a bpf map which can then be consumed by the bpf prog to make decision. In this case, decide which SO_REUSEPORT sk to serve the incoming request. By adding BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, the userspace has total control and visibility on where a SO_REUSEPORT sk should be located in a bpf map. The later patch will introduce BPF_PROG_TYPE_SK_REUSEPORT such that the bpf prog can directly select a sk from the bpf map. That will raise the programmability of the bpf prog attached to a reuseport group (a group of sk serving the same IP:PORT). For example, in UDP, the bpf prog can peek into the payload (e.g. through the "data" pointer introduced in the later patch) to learn the application level's connection information and then decide which sk to pick from a bpf map. The userspace can tightly couple the sk's location in a bpf map with the application logic in generating the UDP payload's connection information. This connection info contact/API stays within the userspace. Also, when used with map-in-map, the userspace can switch the old-server-process's inner map to a new-server-process's inner map in one call "bpf_map_update_elem(outer_map, &index, &new_reuseport_array)". The bpf prog will then direct incoming requests to the new process instead of the old process. The old process can finish draining the pending requests (e.g. by "accept()") before closing the old-fds. [Note that deleting a fd from a bpf map does not necessary mean the fd is closed] During map_update_elem(), Only SO_REUSEPORT sk (i.e. which has already been added to a reuse->socks[]) can be used. That means a SO_REUSEPORT sk that is "bind()" for UDP or "bind()+listen()" for TCP. These conditions are ensured in "reuseport_array_update_check()". A SO_REUSEPORT sk can only be added once to a map (i.e. the same sk cannot be added twice even to the same map). SO_REUSEPORT already allows another sk to be created for the same IP:PORT. There is no need to re-create a similar usage in the BPF side. When a SO_REUSEPORT is deleted from the "reuse->socks[]" (e.g. "close()"), it will notify the bpf map to remove it from the map also. It is done through "bpf_sk_reuseport_detach()" and it will only be called if >=1 of the "reuse->sock[]" has ever been added to a bpf map. The map_update()/map_delete() has to be in-sync with the "reuse->socks[]". Hence, the same "reuseport_lock" used by "reuse->socks[]" has to be used here also. Care has been taken to ensure the lock is only acquired when the adding sk passes some strict tests. and freeing the map does not require the reuseport_lock. The reuseport_array will also support lookup from the syscall side. It will return a sock_gen_cookie(). The sock_gen_cookie() is on-demand (i.e. a sk's cookie is not generated until the very first map_lookup_elem()). The lookup cookie is 64bits but it goes against the logical userspace expectation on 32bits sizeof(fd) (and as other fd based bpf maps do also). It may catch user in surprise if we enforce value_size=8 while userspace still pass a 32bits fd during update. Supporting different value_size between lookup and update seems unintuitive also. We also need to consider what if other existing fd based maps want to return 64bits value from syscall's lookup in the future. Hence, reuseport_array supports both value_size 4 and 8, and assuming user will usually use value_size=4. The syscall's lookup will return ENOSPC on value_size=4. It will will only return 64bits value from sock_gen_cookie() when user consciously choose value_size=8 (as a signal that lookup is desired) which then requires a 64bits value in both lookup and update. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-10bpf: btf: add pretty print for hash/lru_hash mapsYonghong Song1-0/+44
Commit a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap") added pretty print support to array map. This patch adds pretty print for hash and lru_hash maps. The following example shows the pretty-print result of a pinned hashmap: struct map_value { int count_a; int count_b; }; cat /sys/fs/bpf/pinned_hash_map: 87907: {87907,87908} 57354: {37354,57355} 76625: {76625,76626} ... Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-10bpf: fix bpffs non-array map seq_show issueYonghong Song1-3/+5
In function map_seq_next() of kernel/bpf/inode.c, the first key will be the "0" regardless of the map type. This works for array. But for hash type, if it happens key "0" is in the map, the bpffs map show will miss some items if the key "0" is not the first element of the first bucket. This patch fixed the issue by guaranteeing to get the first element, if the seq_show is just started, by passing NULL pointer key to map_get_next_key() callback. This way, no missing elements will occur for bpffs hash table show even if key "0" is in the map. Fixes: a26ca7c982cb5 ("bpf: btf: Add pretty print support to the basic arraymap") Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09xdp: fix bug in devmap teardown code pathJesper Dangaard Brouer1-5/+9
Like cpumap teardown, the devmap teardown code also flush remaining xdp_frames, via bq_xmit_all() in case map entry is removed. The code can call xdp_return_frame_rx_napi, from the the wrong context, in-case ndo_xdp_xmit() fails. Fixes: 389ab7f01af9 ("xdp: introduce xdp_return_frame_rx_napi") Fixes: 735fc4054b3a ("xdp: change ndo_xdp_xmit API to support bulking") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09xdp: fix bug in cpumap teardown code pathJesper Dangaard Brouer1-6/+9
When removing a cpumap entry, a number of syncronization steps happen. Eventually the teardown code __cpu_map_entry_free is invoked from/via call_rcu. The teardown code __cpu_map_entry_free() flushes remaining xdp_frames, by invoking bq_flush_to_queue, which calls xdp_return_frame_rx_napi(). The issues is that the teardown code is not running in the RX NAPI code path. Thus, it is not allowed to invoke the NAPI variant of xdp_return_frame. This bug was found and triggered by using the --stress-mode option to the samples/bpf program xdp_redirect_cpu. It is hard to trigger, because the ptr_ring have to be full and cpumap bulk queue max contains 8 packets, and a remote CPU is racing to empty the ptr_ring queue. Fixes: 389ab7f01af9 ("xdp: introduce xdp_return_frame_rx_napi") Tested-by: Jean-Tsung Hsiao <jhsiao@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-08bpf, sockmap: fix leak in bpf_tcp_sendmsg wait for mem pathDaniel Borkmann1-2/+5
In bpf_tcp_sendmsg() the sk_alloc_sg() may fail. In the case of ENOMEM, it may also mean that we've partially filled the scatterlist entries with pages. Later jumping to sk_stream_wait_memory() we could further fail with an error for several reasons, however we miss to call free_start_sg() if the local sk_msg_buff was used. Fixes: 4f738adba30a ("bpf: create tcp_bpf_ulp allowing BPF to monitor socket TX/RX data") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-08bpf, sockmap: fix bpf_tcp_sendmsg sock error handlingDaniel Borkmann1-1/+1
While working on bpf_tcp_sendmsg() code, I noticed that when a sk->sk_err is set we error out with err = sk->sk_err. However this is problematic since sk->sk_err is a positive error value and therefore we will neither go into sk_stream_error() nor will we report an error back to user space. I had this case with EPIPE and user space was thinking sendmsg() succeeded since EPIPE is a positive value, thinking we submitted 32 bytes. Fix it by negating the sk->sk_err value. Fixes: 4f738adba30a ("bpf: create tcp_bpf_ulp allowing BPF to monitor socket TX/RX data") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller8-124/+617
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-08-07 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add cgroup local storage for BPF programs, which provides a fast accessible memory for storing various per-cgroup data like number of transmitted packets, etc, from Roman. 2) Support bpf_get_socket_cookie() BPF helper in several more program types that have a full socket available, from Andrey. 3) Significantly improve the performance of perf events which are reported from BPF offload. Also convert a couple of BPF AF_XDP samples overto use libbpf, both from Jakub. 4) seg6local LWT provides the End.DT6 action, which allows to decapsulate an outer IPv6 header containing a Segment Routing Header. Adds this action now to the seg6local BPF interface, from Mathieu. 5) Do not mark dst register as unbounded in MOV64 instruction when both src and dst register are the same, from Arthur. 6) Define u_smp_rmb() and u_smp_wmb() to their respective barrier instructions on arm64 for the AF_XDP sample code, from Brian. 7) Convert the tcp_client.py and tcp_server.py BPF selftest scripts over from Python 2 to Python 3, from Jeremy. 8) Enable BTF build flags to the BPF sample code Makefile, from Taeung. 9) Remove an unnecessary rcu_read_lock() in run_lwt_bpf(), from Taehee. 10) Several improvements to the README.rst from the BPF documentation to make it more consistent with RST format, from Tobin. 11) Replace all occurrences of strerror() by calls to strerror_r() in libbpf and fix a FORTIFY_SOURCE build error along with it, from Thomas. 12) Fix a bug in bpftool's get_btf() function to correctly propagate an error via PTR_ERR(), from Yue. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-07bpf: introduce update_effective_progs()Roman Gushchin1-54/+45
__cgroup_bpf_attach() and __cgroup_bpf_detach() functions have a good amount of duplicated code, which is possible to eliminate by introducing the update_effective_progs() helper function. The update_effective_progs() calls compute_effective_progs() and then in case of success it calls activate_effective_progs() for each descendant cgroup. In case of failure (OOM), it releases allocated prog arrays and return the error code. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-05Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-3/+10
Lots of overlapping changes, mostly trivial in nature. The mlxsw conflict was resolving using the example resolution at: https://github.com/jpirko/linux_mlxsw/blob/combined_queue/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-05Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-2/+2
Pull timer fixes from Thomas Gleixner: "Two oneliners addressing NOHZ failures: - Use a bitmask to check for the pending timer softirq and not the bit number. The existing code using the bit number checked for the wrong bit, which caused timers to either expire late or stop completely. - Make the nohz evaluation on interrupt exit more robust. The existing code did not re-arm the hardware when interrupting a running softirq in task context (ksoftirqd or tail of local_bh_enable()), which caused timers to either expire late or stop completely" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: nohz: Fix missing tick reprogram when interrupting an inline softirq nohz: Fix local_timer_softirq_pending()
2018-08-03nohz: Fix missing tick reprogram when interrupting an inline softirqFrederic Weisbecker1-1/+1
The full nohz tick is reprogrammed in irq_exit() only if the exit is not in a nesting interrupt. This stands as an optimization: whether a hardirq or a softirq is interrupted, the tick is going to be reprogrammed when necessary at the end of the inner interrupt, with even potential new updates on the timer queue. When soft interrupts are interrupted, it's assumed that they are executing on the tail of an interrupt return. In that case tick_nohz_irq_exit() is called after softirq processing to take care of the tick reprogramming. But the assumption is wrong: softirqs can be processed inline as well, ie: outside of an interrupt, like in a call to local_bh_enable() or from ksoftirqd. Inline softirqs don't reprogram the tick once they are done, as opposed to interrupt tail softirq processing. So if a tick interrupts an inline softirq processing, the next timer will neither be reprogrammed from the interrupting tick's irq_exit() nor after the interrupted softirq processing. This situation may leave the tick unprogrammed while timers are armed. To fix this, simply keep reprogramming the tick even if a softirq has been interrupted. That can be optimized further, but for now correctness is more important. Note that new timers enqueued in nohz_full mode after a softirq gets interrupted will still be handled just fine through self-IPIs triggered by the timer code. Reported-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: stable@vger.kernel.org # 4.14+ Link: https://lkml.kernel.org/r/1533303094-15855-1-git-send-email-frederic@kernel.org
2018-08-03genirq: Make force irq threading setup more robustThomas Gleixner1-1/+8
The support of force threading interrupts which are set up with both a primary and a threaded handler wreckaged the setup of regular requested threaded interrupts (primary handler == NULL). The reason is that it does not check whether the primary handler is set to the default handler which wakes the handler thread. Instead it replaces the thread handler with the primary handler as it would do with force threaded interrupts which have been requested via request_irq(). So both the primary and the thread handler become the same which then triggers the warnon that the thread handler tries to wakeup a not configured secondary thread. Fortunately this only happens when the driver omits the IRQF_ONESHOT flag when requesting the threaded interrupt, which is normaly caught by the sanity checks when force irq threading is disabled. Fix it by skipping the force threading setup when a regular threaded interrupt is requested. As a consequence the interrupt request which lacks the IRQ_ONESHOT flag is rejected correctly instead of silently wreckaging it. Fixes: 2a1d3ab8986d ("genirq: Handle force threading of irqs with primary and thread handler") Reported-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de> Cc: stable@vger.kernel.org
2018-08-03bpf: introduce the bpf_get_local_storage() helper functionRoman Gushchin4-0/+41
The bpf_get_local_storage() helper function is used to get a pointer to the bpf local storage from a bpf program. It takes a pointer to a storage map and flags as arguments. Right now it accepts only cgroup storage maps, and flags argument has to be 0. Further it can be extended to support other types of local storage: e.g. thread local storage etc. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: don't allow create maps of cgroup local storagesRoman Gushchin1-1/+2
As there is one-to-one relation between a bpf program and cgroup local storage map, there is no sense in creating a map of cgroup local storage maps. Forbid it explicitly to avoid possible side effects. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf/verifier: introduce BPF_PTR_TO_MAP_VALUERoman Gushchin1-2/+6
BPF_MAP_TYPE_CGROUP_STORAGE maps are special in a way that the access from the bpf program side is lookup-free. That means the result is guaranteed to be a valid pointer to the cgroup storage; no NULL-check is required. This patch introduces BPF_PTR_TO_MAP_VALUE return type, which is required to cause the verifier accept programs, which are not checking the map value pointer for being NULL. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: extend bpf_prog_array to store pointers to the cgroup storageRoman Gushchin2-46/+51
This patch converts bpf_prog_array from an array of prog pointers to the array of struct bpf_prog_array_item elements. This allows to save a cgroup storage pointer for each bpf program efficiently attached to a cgroup. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: allocate cgroup storage entries on attaching bpf programsRoman Gushchin1-4/+31
If a bpf program is using cgroup local storage, allocate a bpf_cgroup_storage structure automatically on attaching the program to a cgroup and save the pointer into the corresponding bpf_prog_list entry. Analogically, release the cgroup local storage on detaching of the bpf program. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: pass a pointer to a cgroup storage using pcpu variableRoman Gushchin1-0/+2
This commit introduces the bpf_cgroup_storage_set() helper, which will be used to pass a pointer to a cgroup storage to the bpf helper. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: introduce cgroup storage mapsRoman Gushchin4-0/+392
This commit introduces BPF_MAP_TYPE_CGROUP_STORAGE maps: a special type of maps which are implementing the cgroup storage. >From the userspace point of view it's almost a generic hash map with the (cgroup inode id, attachment type) pair used as a key. The only difference is that some operations are restricted: 1) a user can't create new entries, 2) a user can't remove existing entries. The lookup from userspace is o(log(n)). Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-03bpf: add ability to charge bpf maps memory dynamicallyRoman Gushchin1-15/+43
This commits extends existing bpf maps memory charging API to support dynamic charging/uncharging. This is required to account memory used by maps, if all entries are created dynamically after the map initialization. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-02Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller16-30/+151
The BTF conflicts were simple overlapping changes. The virtio_net conflict was an overlap of a fix of statistics counter, happening alongisde a move over to a bonafide statistics structure rather than counting value on the stack. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-31Merge tag 'audit-pr-20180731' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/auditLinus Torvalds1-4/+9
Pull audit fix from Paul Moore: "A single small audit fix to guard against memory allocation failures when logging information about a kernel module load. It's small, easy to understand, and self-contained; while nothing is zero risk, this should be pretty low" * tag 'audit-pr-20180731' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: fix potential null dereference 'context->module.name'
2018-07-31bpf: verifier: MOV64 don't mark dst reg unboundedArthur Fabre1-2/+4
When check_alu_op() handles a BPF_MOV64 between two registers, it calls check_reg_arg(DST_OP) on the dst register, marking it as unbounded. If the src and dst register are the same, this marks the src as unbounded, which can lead to unexpected errors for further checks that rely on bounds info. For example: BPF_MOV64_IMM(BPF_REG_2, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_2), BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_2), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), Results in: "math between ctx pointer and register with unbounded min value is not allowed" check_alu_op() now uses check_reg_arg(DST_OP_NO_MARK), and MOVs that need to mark the dst register (MOVIMM, MOV32) do so. Added a test case for MOV64 dst == src, and dst != src. Signed-off-by: Arthur Fabre <afabre@cloudflare.com> Acked-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-31nohz: Fix local_timer_softirq_pending()Anna-Maria Gleixner1-1/+1
local_timer_softirq_pending() checks whether the timer softirq is pending with: local_softirq_pending() & TIMER_SOFTIRQ. This is wrong because TIMER_SOFTIRQ is the softirq number and not a bitmask. So the test checks for the wrong bit. Use BIT(TIMER_SOFTIRQ) instead. Fixes: 5d62c183f9e9 ("nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()") Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Cc: bigeasy@linutronix.de Cc: peterz@infradead.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180731161358.29472-1-anna-maria@linutronix.de
2018-07-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2-2/+14
Pull networking fixes from David Miller: "Several smallish fixes, I don't think any of this requires another -rc but I'll leave that up to you: 1) Don't leak uninitialzed bytes to userspace in xfrm_user, from Eric Dumazet. 2) Route leak in xfrm_lookup_route(), from Tommi Rantala. 3) Premature poll() returns in AF_XDP, from Björn Töpel. 4) devlink leak in netdevsim, from Jakub Kicinski. 5) Don't BUG_ON in fib_compute_spec_dst, the condition can legitimately happen. From Lorenzo Bianconi. 6) Fix some spectre v1 gadgets in generic socket code, from Jeremy Cline. 7) Don't allow user to bind to out of range multicast groups, from Dmitry Safonov with a follow-up by Dmitry Safonov. 8) Fix metrics leak in fib6_drop_pcpu_from(), from Sabrina Dubroca" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits) netlink: Don't shift with UB on nlk->ngroups net/ipv6: fix metrics leak xen-netfront: wait xenbus state change when load module manually can: ems_usb: Fix memory leak on ems_usb_disconnect() openvswitch: meter: Fix setting meter id for new entries netlink: Do not subscribe to non-existent groups NET: stmmac: align DMA stuff to largest cache line length tcp_bbr: fix bw probing to raise in-flight data for very small BDPs net: socket: Fix potential spectre v1 gadget in sock_is_registered net: socket: fix potential spectre v1 gadget in socketcall net: mdio-mux: bcm-iproc: fix wrong getter and setter pair ipv4: remove BUG_ON() from fib_compute_spec_dst enic: handle mtu change for vf properly net: lan78xx: fix rx handling before first packet is send nfp: flower: fix port metadata conversion bug bpf: use GFP_ATOMIC instead of GFP_KERNEL in bpf_parse_prog() bpf: fix bpf_skb_load_bytes_relative pkt length check perf build: Build error in libbpf missing initialization net: ena: Fix use of uninitialized DMA address bits field bpf: btf: Use exact btf value_size match in map_check_btf() ...
2018-07-30audit: fix potential null dereference 'context->module.name'Yi Wang1-4/+9
The variable 'context->module.name' may be null pointer when kmalloc return null, so it's better to check it before using to avoid null dereference. Another one more thing this patch does is using kstrdup instead of (kmalloc + strcpy), and signal a lost record via audit_log_lost. Cc: stable@vger.kernel.org # 4.11 Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-07-30Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-3/+19
Pull scheduler fixes from Ingo Molnar: "Misc fixes: - a deadline scheduler related bug fix which triggered a kernel warning - an RT_RUNTIME_SHARE fix - a stop_machine preemption fix - a potential NULL dereference fix in sched_domain_debug_one()" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHARE sched/deadline: Update rq_clock of later_rq when pushing a task stop_machine: Disable preemption after queueing stopper threads sched/topology: Check variable group before dereferencing it
2018-07-30Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+8
Pull perf fixes from Ingo Molnar: "Misc fixes: - AMD IBS data corruptor fix (uncovered by UBSAN) - an Intel PEBS entry unwind error fix - a HW-tracing crash fix - a MAINTAINERS update" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Fix crash when using HW tracing kernel filters perf/x86/intel: Fix unwind errors from PEBS entries (mk-II) MAINTAINERS: Add Naveen N. Rao as kprobes co-maintainer perf/x86/amd/ibs: Don't access non-started event
2018-07-30Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-4/+25
Pull locking fixes from Ingo Molnar: "A paravirt UP-patching fix, and an I2C MUX driver lockdep warning fix" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/pvqspinlock/x86: Use LOCK_PREFIX in __pv_queued_spin_unlock() assembly code i2c/mux, locking/core: Annotate the nested rt_mutex usage locking/rtmutex: Allow specifying a subclass for nested locking
2018-07-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2-2/+14
Daniel Borkmann says: ==================== pull-request: bpf 2018-07-28 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) API fixes for libbpf's BTF mapping of map key/value types in order to make them compatible with iproute2's BPF_ANNOTATE_KV_PAIR() markings, from Martin. 2) Fix AF_XDP to not report POLLIN prematurely by using the non-cached consumer pointer of the RX queue, from Björn. 3) Fix __xdp_return() to check for NULL pointer after the rhashtable lookup that retrieves the allocator object, from Taehee. 4) Fix x86-32 JIT to adjust ebp register in prologue and epilogue by 4 bytes which got removed from overall stack usage, from Wang. 5) Fix bpf_skb_load_bytes_relative() length check to use actual packet length, from Daniel. 6) Fix uninitialized return code in libbpf bpf_perf_event_read_simple() handler, from Thomas. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-27Merge branch 'akpm' (patches from Andrew)Linus Torvalds2-7/+21
Merge misc fixes from Andrew Morton: "11 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: kvm, mm: account shadow page tables to kmemcg zswap: re-check zswap_is_full() after do zswap_shrink() include/linux/eventfd.h: include linux/errno.h mm: fix vma_is_anonymous() false-positives mm: use vma_init() to initialize VMAs on stack and data segments mm: introduce vma_init() mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL ipc/sem.c: prevent queue.status tearing in semop mm: disallow mappings that conflict for devm_memremap_pages() kasan: only select SLUB_DEBUG with SYSFS=y delayacct: fix crash in delayacct_blkio_end() after delayacct init failure
2018-07-27Merge tag 'trace-v4.18-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds5-8/+55
Pull tracing fixes from Steven Rostedt: "Various fixes to the tracing infrastructure: - Fix double free when the reg() call fails in event_trigger_callback() - Fix anomoly of snapshot causing tracing_on flag to change - Add selftest to test snapshot and tracing_on affecting each other - Fix setting of tracepoint flag on error that prevents probes from being deleted. - Fix another possible double free that is similar to event_trigger_callback() - Quiet a gcc warning of a false positive unused variable - Fix crash of partial exposed task->comm to trace events" * tag 'trace-v4.18-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: kthread, tracing: Don't expose half-written comm when creating kthreads tracing: Quiet gcc warning about maybe unused link variable tracing: Fix possible double free in event_enable_trigger_func() tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure selftests/ftrace: Add snapshot and tracing_on test case ring_buffer: tracing: Inherit the tracing setting to next ring buffer tracing: Fix double free of event_trigger_data
2018-07-26mm: introduce vma_init()Kirill A. Shutemov1-4/+2
Not all VMAs allocated with vm_area_alloc(). Some of them allocated on stack or in data segment. The new helper can be use to initialize VMA properly regardless where it was allocated. Link: http://lkml.kernel.org/r/20180724121139.62570-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-26mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPLDan Williams1-2/+2
Commit e76384884344 ("mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS") added two EXPORT_SYMBOL_GPL() symbols, but these symbols are required by the inlined put_page(), thus accidentally making put_page() a GPL export only. This breaks OpenAFS (at least). Mark them EXPORT_SYMBOL() instead. Link: http://lkml.kernel.org/r/153128611970.2928.11310692420711601254.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: e76384884344 ("mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Joe Gorse <jhgorse@gmail.com> Reported-by: John Hubbard <jhubbard@nvidia.com> Tested-by: Joe Gorse <jhgorse@gmail.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Mark Vitale <mvitale@sinenomine.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-26mm: disallow mappings that conflict for devm_memremap_pages()Dave Jiang1-1/+17
When pmem namespaces created are smaller than section size, this can cause an issue during removal and gpf was observed: general protection fault: 0000 1 SMP PTI CPU: 36 PID: 3941 Comm: ndctl Tainted: G W 4.14.28-1.el7uek.x86_64 #2 task: ffff88acda150000 task.stack: ffffc900233a4000 RIP: 0010:__put_page+0x56/0x79 Call Trace: devm_memremap_pages_release+0x155/0x23a release_nodes+0x21e/0x260 devres_release_all+0x3c/0x48 device_release_driver_internal+0x15c/0x207 device_release_driver+0x12/0x14 unbind_store+0xba/0xd8 drv_attr_store+0x27/0x31 sysfs_kf_write+0x3f/0x46 kernfs_fop_write+0x10f/0x18b __vfs_write+0x3a/0x16d vfs_write+0xb2/0x1a1 SyS_write+0x55/0xb9 do_syscall_64+0x79/0x1ae entry_SYSCALL_64_after_hwframe+0x3d/0x0 Add code to check whether we have a mapping already in the same section and prevent additional mappings from being created if that is the case. Link: http://lkml.kernel.org/r/152909478401.50143.312364396244072931.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Robert Elliott <elliott@hpe.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-27bpf: btf: Use exact btf value_size match in map_check_btf()Martin KaFai Lau1-1/+1
The current map_check_btf() in BPF_MAP_TYPE_ARRAY rejects '> map->value_size' to ensure map_seq_show_elem() will not access things beyond an array element. Yonghong suggested that using '!=' is a more correct check. The 8 bytes round_up on value_size is stored in array->elem_size. Hence, using '!=' on map->value_size is a proper check. This patch also adds new tests to check the btf array key type and value type. Two of these new tests verify the btf's value_size (the change in this patch). It also fixes two existing tests that wrongly encoded a btf's type size (pprint_test) and the value_type_id (in one of the raw_tests[]). However, that do not affect these two BTF verification tests before or after this test changes. These two tests mainly failed at array creation time after this patch. Fixes: a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap") Suggested-by: Yonghong Song <yhs@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-26kthread, tracing: Don't expose half-written comm when creating kthreadsSnild Dolkow1-1/+7
There is a window for racing when printing directly to task->comm, allowing other threads to see a non-terminated string. The vsnprintf function fills the buffer, counts the truncated chars, then finally writes the \0 at the end. creator other vsnprintf: fill (not terminated) count the rest trace_sched_waking(p): ... memcpy(comm, p->comm, TASK_COMM_LEN) write \0 The consequences depend on how 'other' uses the string. In our case, it was copied into the tracing system's saved cmdlines, a buffer of adjacent TASK_COMM_LEN-byte buffers (note the 'n' where 0 should be): crash-arm64> x/1024s savedcmd->saved_cmdlines | grep 'evenk' 0xffffffd5b3818640: "irq/497-pwr_evenkworker/u16:12" ...and a strcpy out of there would cause stack corruption: [224761.522292] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffff9bf9783c78 crash-arm64> kbt | grep 'comm\|trace_print_context' #6 0xffffff9bf9783c78 in trace_print_context+0x18c(+396) comm (char [16]) = "irq/497-pwr_even" crash-arm64> rd 0xffffffd4d0e17d14 8 ffffffd4d0e17d14: 2f71726900000000 5f7277702d373934 ....irq/497-pwr_ ffffffd4d0e17d24: 726f776b6e657665 3a3631752f72656b evenkworker/u16: ffffffd4d0e17d34: f9780248ff003231 cede60e0ffffff9b 12..H.x......`.. ffffffd4d0e17d44: cede60c8ffffffd4 00000fffffffffd4 .....`.......... The workaround in e09e28671 (use strlcpy in __trace_find_cmdline) was likely needed because of this same bug. Solved by vsnprintf:ing to a local buffer, then using set_task_comm(). This way, there won't be a window where comm is not terminated. Link: http://lkml.kernel.org/r/20180726071539.188015-1-snild@sony.com Cc: stable@vger.kernel.org Fixes: bc0c38d139ec7 ("ftrace: latency tracer infrastructure") Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Snild Dolkow <snild@sony.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25tracing: Quiet gcc warning about maybe unused link variableSteven Rostedt (VMware)1-2/+4
Commit 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure") added an if statement that depends on another if statement that gcc doesn't see will initialize the "link" variable and gives the warning: "warning: 'link' may be used uninitialized in this function" It is really a false positive, but to quiet the warning, and also to make sure that it never actually is used uninitialized, initialize the "link" variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler thinks it could be used uninitialized. Cc: stable@vger.kernel.org Fixes: 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25tracing: Fix possible double free in event_enable_trigger_func()Steven Rostedt (VMware)1-1/+5
There was a case that triggered a double free in event_trigger_callback() due to the called reg() function freeing the trigger_data and then it getting freed again by the error return by the caller. The solution there was to up the trigger_data ref count. Code inspection found that event_enable_trigger_func() has the same issue, but is not as easy to trigger (requires harder to trigger failures). It needs to be solved slightly different as it needs more to clean up when the reg() function fails. Link: http://lkml.kernel.org/r/20180725124008.7008e586@gandalf.local.home Cc: stable@vger.kernel.org Fixes: 7862ad1846e99 ("tracing: Add 'enable_event' and 'disable_event' event trigger commands") Reivewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failureArtem Savkov1-2/+11
If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe it returns an error, but does not unset the tp flags it set previously. This results in a probe being considered enabled and failures like being unable to remove the probe through kprobe_events file since probes_open() expects every probe to be disabled. Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 41a7dd420c57 ("tracing/kprobes: Support ftrace_event_file base multibuffer") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Artem Savkov <asavkov@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25ring_buffer: tracing: Inherit the tracing setting to next ring bufferMasami Hiramatsu2-0/+22
Maintain the tracing on/off setting of the ring_buffer when switching to the trace buffer snapshot. Taking a snapshot is done by swapping the backup ring buffer (max_tr_buffer). But since the tracing on/off setting is defined by the ring buffer, when swapping it, the tracing on/off setting can also be changed. This causes a strange result like below: /sys/kernel/debug/tracing # cat tracing_on 1 /sys/kernel/debug/tracing # echo 0 > tracing_on /sys/kernel/debug/tracing # cat tracing_on 0 /sys/kernel/debug/tracing # echo 1 > snapshot /sys/kernel/debug/tracing # cat tracing_on 1 /sys/kernel/debug/tracing # echo 1 > snapshot /sys/kernel/debug/tracing # cat tracing_on 0 We don't touch tracing_on, but snapshot changes tracing_on setting each time. This is an anomaly, because user doesn't know that each "ring_buffer" stores its own tracing-enable state and the snapshot is done by swapping ring buffers. Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox Cc: Ingo Molnar <mingo@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp> Cc: stable@vger.kernel.org Fixes: debdd57f5145 ("tracing: Make a snapshot feature available from userspace") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ Updated commit log and comment in the code ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25tracing: Fix double free of event_trigger_dataSteven Rostedt (VMware)1-4/+8
Running the following: # cd /sys/kernel/debug/tracing # echo 500000 > buffer_size_kb [ Or some other number that takes up most of memory ] # echo snapshot > events/sched/sched_switch/trigger Triggers the following bug: ------------[ cut here ]------------ kernel BUG at mm/slub.c:296! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kfree+0x16c/0x180 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00 FS: 00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0 Call Trace: event_trigger_callback+0xee/0x1d0 event_trigger_write+0xfc/0x1a0 __vfs_write+0x33/0x190 ? handle_mm_fault+0x115/0x230 ? _cond_resched+0x16/0x40 vfs_write+0xb0/0x190 ksys_write+0x52/0xc0 do_syscall_64+0x5a/0x160 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f363e16ab50 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper 86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e ---[ end trace d301afa879ddfa25 ]--- The cause is because the register_snapshot_trigger() call failed to allocate the snapshot buffer, and then called unregister_trigger() which freed the data that was passed to it. Then on return to the function that called register_snapshot_trigger(), as it sees it failed to register, it frees the trigger_data again and causes a double free. By calling event_trigger_init() on the trigger_data (which only ups the reference counter for it), and then event_trigger_free() afterward, the trigger_data would not get freed by the registering trigger function as it would only up and lower the ref count for it. If the register trigger function fails, then the event_trigger_free() called after it will free the trigger data normally. Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home Cc: stable@vger.kerne.org Fixes: 93e31ffbf417 ("tracing: Add 'snapshot' event trigger command") Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25perf/core: Fix crash when using HW tracing kernel filtersMathieu Poirier1-0/+4
In function perf_event_parse_addr_filter(), the path::dentry of each struct perf_addr_filter is left unassigned (as it should be) when the pattern being parsed is related to kernel space. But in function perf_addr_filter_match() the same dentries are given to d_inode() where the value is not expected to be NULL, resulting in the following splat: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058 pc : perf_event_mmap+0x2fc/0x5a0 lr : perf_event_mmap+0x2c8/0x5a0 Process uname (pid: 2860, stack limit = 0x000000001cbcca37) Call trace: perf_event_mmap+0x2fc/0x5a0 mmap_region+0x124/0x570 do_mmap+0x344/0x4f8 vm_mmap_pgoff+0xe4/0x110 vm_mmap+0x2c/0x40 elf_map+0x60/0x108 load_elf_binary+0x450/0x12c4 search_binary_handler+0x90/0x290 __do_execve_file.isra.13+0x6e4/0x858 sys_execve+0x3c/0x50 el0_svc_naked+0x30/0x34 This patch is fixing the problem by introducing a new check in function perf_addr_filter_match() to see if the filter's dentry is NULL. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Cc: miklos@szeredi.hu Cc: namhyung@kernel.org Cc: songliubraving@fb.com Fixes: 9511bce9fe8e ("perf/core: Fix bad use of igrab()") Link: http://lkml.kernel.org/r/1531782831-1186-1-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)Peter Zijlstra1-2/+4
Vince reported the perf_fuzzer giving various unwinder warnings and Josh reported: > Deja vu. Most of these are related to perf PEBS, similar to the > following issue: > > b8000586c90b ("perf/x86/intel: Cure bogus unwind from PEBS entries") > > This is basically the ORC version of that. setup_pebs_sample_data() is > assembling a franken-pt_regs which ORC isn't happy about. RIP is > inconsistent with some of the other registers (like RSP and RBP). And where the previous unwinder only needed BP,SP ORC also requires IP. But we cannot spoof IP because then the sample will get displaced, entirely negating the point of PEBS. So cure the whole thing differently by doing the unwind early; this does however require a means to communicate we did the unwind early. We (ab)use an unused sample_type bit for this, which we set on events that fill out the data->callchain before the normal perf_prepare_sample(). Debugged-by: Josh Poimboeuf <jpoimboe@redhat.com> Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHAREHailong Liu1-0/+2
NO_RT_RUNTIME_SHARE feature is used to prevent a CPU borrow enough runtime with a spin-rt-task. However, if RT_RUNTIME_SHARE feature is enabled and rt_rq has borrowd enough rt_runtime at the beginning, rt_runtime can't be restored to its initial bandwidth rt_runtime after we disable RT_RUNTIME_SHARE. E.g. on my PC with 4 cores, procedure to reproduce: 1) Make sure RT_RUNTIME_SHARE is enabled cat /sys/kernel/debug/sched_features GENTLE_FAIR_SLEEPERS START_DEBIT NO_NEXT_BUDDY LAST_BUDDY CACHE_HOT_BUDDY WAKEUP_PREEMPTION NO_HRTICK NO_DOUBLE_TICK LB_BIAS NONTASK_CAPACITY TTWU_QUEUE NO_SIS_AVG_CPU SIS_PROP NO_WARN_DOUBLE_CLOCK RT_PUSH_IPI RT_RUNTIME_SHARE NO_LB_MIN ATTACH_AGE_LOAD WA_IDLE WA_WEIGHT WA_BIAS 2) Start a spin-rt-task ./loop_rr & 3) set affinity to the last cpu taskset -p 8 $pid_of_loop_rr 4) Observe that last cpu have borrowed enough runtime. cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 5) Disable RT_RUNTIME_SHARE echo NO_RT_RUNTIME_SHARE > /sys/kernel/debug/sched_features 6) Observe that rt_runtime can not been restored cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 This patch help to restore rt_runtime after we disable RT_RUNTIME_SHARE. Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn> Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: zhong.weidong@zte.com.cn Link: http://lkml.kernel.org/r/1531874815-39357-1-git-send-email-liu.hailong6@zte.com.cn Signed-off-by: Ingo Molnar <mingo@kernel.org>