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2023-06-20Merge tag 'trace-v6.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix MAINTAINERS file to point to proper mailing list for rtla and rv The mailing list pointed to linux-trace-devel instead of linux-trace-kernel. The former is for the tracing libraries and the latter is for anything in the Linux kernel tree. The wrong mailing list was used because linux-trace-kernel did not exist when rtla and rv were created. - User events: - Fix matching of dynamic events to their user events When user writes to dynamic_events file, a lookup of the registered dynamic events is made, but there were some cases that a match could be incorrectly made. - Add auto cleanup of user events Have the user events automatically get removed when the last reference (file descriptor) is closed. This was asked for to prevent leaks of user events hanging around needing admins to clean them up. - Add persistent logic (but not let user space use it yet) In some cases, having a persistent user event (one that does not get cleaned up automatically) is useful. But there's still debates about how to expose this to user space. The infrastructure is added, but the API is not. - Update the selftests Update the user event selftests to reflect the above changes" * tag 'trace-v6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/user_events: Document auto-cleanup and remove dyn_event refs selftests/user_events: Adapt dyn_test to non-persist events selftests/user_events: Ensure auto cleanup works as expected tracing/user_events: Add auto cleanup and future persist flag tracing/user_events: Track refcount consistently via put/get tracing/user_events: Store register flags on events tracing/user_events: Remove user_ns walk for groups selftests/user_events: Add perf self-test for empty arguments events selftests/user_events: Clear the events after perf self-test selftests/user_events: Add ftrace self-test for empty arguments events tracing/user_events: Fix the incorrect trace record for empty arguments events tracing: Modify print_fields() for fields output order tracing/user_events: Handle matching arguments that is null from dyn_events tracing/user_events: Prevent same name but different args event tracing/rv/rtla: Update MAINTAINERS file to point to proper mailing list
2023-06-14tracing/user_events: Add auto cleanup and future persist flagBeau Belgrave
Currently user events need to be manually deleted via the delete IOCTL call or via the dynamic_events file. Most operators and processes wish to have these events auto cleanup when they are no longer used by anything to prevent them piling without manual maintenance. However, some operators may not want this, such as pre-registering events via the dynamic_events tracefs file. Update user_event_put() to attempt an auto delete of the event if it's the last reference. The auto delete must run in a work queue to ensure proper behavior of class->reg() invocations that don't expect the call to go away from underneath them during the unregister. Add work_struct to user_event struct to ensure we can do this reliably. Add a persist flag, that is not yet exposed, to ensure we can toggle between auto-cleanup and leaving the events existing in the future. When a non-zero flag is seen during register, return -EINVAL to ensure ABI is clear for the user processes while we work out the best approach for persistent events. Link: https://lkml.kernel.org/r/20230614163336.5797-4-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/20230518093600.3f119d68@rorschach.local.home/ Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Track refcount consistently via put/getBeau Belgrave
Various parts of the code today track user_event's refcnt field directly via a refcount_add/dec. This makes it hard to modify the behavior of the last reference decrement in all code paths consistently. For example, in the future we will auto-delete events upon the last reference going away. This last reference could happen in many places, but we want it to be consistently handled. Add user_event_get() and user_event_put() for the add/dec. Update all places where direct refcounts are being used to utilize these new functions. In each location pass if event_mutex is locked or not. This allows us to drop events automatically in future patches clearly. Ensure when caller states the lock is held, it really is (or is not) held. Link: https://lkml.kernel.org/r/20230614163336.5797-3-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Store register flags on eventsBeau Belgrave
Currently we don't have any available flags for user processes to use to indicate options for user_events. We will soon have a flag to indicate the event should or should not auto-delete once it's not being used by anyone. Add a reg_flags field to user_events and parameters to existing functions to allow for this in future patches. Link: https://lkml.kernel.org/r/20230614163336.5797-2-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Remove user_ns walk for groupsBeau Belgrave
During discussions it was suggested that user_ns is not a good place to try to attach a tracing namespace. The current code has stubs to enable that work that are very likely to change and incur a performance cost. Remove the user_ns walk when creating a group and determining the system name to use, since it's unlikely user_ns will be used in the future. Link: https://lore.kernel.org/all/20230601-urenkel-holzofen-cd9403b9cadd@brauner/ Link: https://lore.kernel.org/linux-trace-kernel/20230601224928.301-1-beaub@linux.microsoft.com Suggested-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Fix the incorrect trace record for empty arguments eventssunliming
The user_events support events that has empty arguments. But the trace event is discarded and not really committed when the arguments is empty. Fix this by not attempting to copy in zero-length data. Link: https://lkml.kernel.org/r/20230606062027.1008398-2-sunliming@kylinos.cn Acked-by: Beau Belgrave <beaub@linux.microsoft.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: sunliming <sunliming@kylinos.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing: Modify print_fields() for fields output ordersunliming
Now the print_fields() print trace event fields in reverse order. Modify it to the positive sequence. Example outputs for a user event: test0 u32 count1; u32 count2 Output before: example-2547 [000] ..... 325.666387: test0: count2=0x2 (2) count1=0x1 (1) Output after: example-2742 [002] ..... 429.769370: test0: count1=0x1 (1) count2=0x2 (2) Link: https://lore.kernel.org/linux-trace-kernel/20230525085232.5096-1-sunliming@kylinos.cn Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields") Signed-off-by: sunliming <sunliming@kylinos.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Handle matching arguments that is null from dyn_eventssunliming
When A registering user event from dyn_events has no argments, it will pass the matching check, regardless of whether there is a user event with the same name and arguments. Add the matching check when the arguments of registering user event is null. Link: https://lore.kernel.org/linux-trace-kernel/20230529065110.303440-1-sunliming@kylinos.cn Signed-off-by: sunliming <sunliming@kylinos.cn> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14tracing/user_events: Prevent same name but different args eventsunliming
User processes register name_args for events. If the same name but different args event are registered. The trace outputs of second event are printed as the first event. This is incorrect. Return EADDRINUSE back to the user process if the same name but different args event has being registered. Link: https://lore.kernel.org/linux-trace-kernel/20230529032100.286534-1-sunliming@kylinos.cn Signed-off-by: sunliming <sunliming@kylinos.cn> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-08Merge tag 'net-6.4-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from can, wifi, netfilter, bluetooth and ebpf. Current release - regressions: - bpf: sockmap: avoid potential NULL dereference in sk_psock_verdict_data_ready() - wifi: iwlwifi: fix -Warray-bounds bug in iwl_mvm_wait_d3_notif() - phylink: actually fix ksettings_set() ethtool call - eth: dwmac-qcom-ethqos: fix a regression on EMAC < 3 Current release - new code bugs: - wifi: mt76: fix possible NULL pointer dereference in mt7996_mac_write_txwi() Previous releases - regressions: - netfilter: fix NULL pointer dereference in nf_confirm_cthelper - wifi: rtw88/rtw89: correct PS calculation for SUPPORTS_DYNAMIC_PS - openvswitch: fix upcall counter access before allocation - bluetooth: - fix use-after-free in hci_remove_ltk/hci_remove_irk - fix l2cap_disconnect_req deadlock - nic: bnxt_en: prevent kernel panic when receiving unexpected PHC_UPDATE event Previous releases - always broken: - core: annotate rfs lockless accesses - sched: fq_pie: ensure reasonable TCA_FQ_PIE_QUANTUM values - netfilter: add null check for nla_nest_start_noflag() in nft_dump_basechain_hook() - bpf: fix UAF in task local storage - ipv4: ping_group_range: allow GID from 2147483648 to 4294967294 - ipv6: rpl: fix route of death. - tcp: gso: really support BIG TCP - mptcp: fixes for user-space PM address advertisement - smc: avoid to access invalid RMBs' MRs in SMCRv1 ADD LINK CONT - can: avoid possible use-after-free when j1939_can_rx_register fails - batman-adv: fix UaF while rescheduling delayed work - eth: qede: fix scheduling while atomic - eth: ice: make writes to /dev/gnssX synchronous" * tag 'net-6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits) bnxt_en: Implement .set_port / .unset_port UDP tunnel callbacks bnxt_en: Prevent kernel panic when receiving unexpected PHC_UPDATE event bnxt_en: Skip firmware fatal error recovery if chip is not accessible bnxt_en: Query default VLAN before VNIC setup on a VF bnxt_en: Don't issue AP reset during ethtool's reset operation bnxt_en: Fix bnxt_hwrm_update_rss_hash_cfg() net: bcmgenet: Fix EEE implementation eth: ixgbe: fix the wake condition eth: bnxt: fix the wake condition lib: cpu_rmap: Fix potential use-after-free in irq_cpu_rmap_release() bpf: Add extra path pointer check to d_path helper net: sched: fix possible refcount leak in tc_chain_tmplt_add() net: sched: act_police: fix sparse errors in tcf_police_dump() net: openvswitch: fix upcall counter access before allocation net: sched: move rtm_tca_policy declaration to include file ice: make writes to /dev/gnssX synchronous net: sched: add rcu annotations around qdisc->qdisc_sleeping rfs: annotate lockless accesses to RFS sock flow table rfs: annotate lockless accesses to sk->sk_rxhash virtio_net: use control_buf for coalesce params ...
2023-06-07Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2023-06-07 We've added 7 non-merge commits during the last 7 day(s) which contain a total of 12 files changed, 112 insertions(+), 7 deletions(-). The main changes are: 1) Fix a use-after-free in BPF's task local storage, from KP Singh. 2) Make struct path handling more robust in bpf_d_path, from Jiri Olsa. 3) Fix a syzbot NULL-pointer dereference in sockmap, from Eric Dumazet. 4) UAPI fix for BPF_NETFILTER before final kernel ships, from Florian Westphal. 5) Fix map-in-map array_map_gen_lookup code generation where elem_size was not being set for inner maps, from Rhys Rustad-Elliott. 6) Fix sockopt_sk selftest's NETLINK_LIST_MEMBERSHIPS assertion, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Add extra path pointer check to d_path helper selftests/bpf: Fix sockopt_sk selftest bpf: netfilter: Add BPF_NETFILTER bpf_attach_type selftests/bpf: Add access_inner_map selftest bpf: Fix elem_size not being set for inner maps bpf: Fix UAF in task local storage bpf, sockmap: Avoid potential NULL dereference in sk_psock_verdict_data_ready() ==================== Link: https://lore.kernel.org/r/20230607220514.29698-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07bpf: Add extra path pointer check to d_path helperJiri Olsa
Anastasios reported crash on stable 5.15 kernel with following BPF attached to lsm hook: SEC("lsm.s/bprm_creds_for_exec") int BPF_PROG(bprm_creds_for_exec, struct linux_binprm *bprm) { struct path *path = &bprm->executable->f_path; char p[128] = { 0 }; bpf_d_path(path, p, 128); return 0; } But bprm->executable can be NULL, so bpf_d_path call will crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI ... RIP: 0010:d_path+0x22/0x280 ... Call Trace: <TASK> bpf_d_path+0x21/0x60 bpf_prog_db9cf176e84498d9_bprm_creds_for_exec+0x94/0x99 bpf_trampoline_6442506293_0+0x55/0x1000 bpf_lsm_bprm_creds_for_exec+0x5/0x10 security_bprm_creds_for_exec+0x29/0x40 bprm_execve+0x1c1/0x900 do_execveat_common.isra.0+0x1af/0x260 __x64_sys_execve+0x32/0x40 It's problem for all stable trees with bpf_d_path helper, which was added in 5.9. This issue is fixed in current bpf code, where we identify and mark trusted pointers, so the above code would fail even to load. For the sake of the stable trees and to workaround potentially broken verifier in the future, adding the code that reads the path object from the passed pointer and verifies it's valid in kernel space. Fixes: 6e22ab9da793 ("bpf: Add d_path helper") Reported-by: Anastasios Papagiannis <tasos.papagiannnis@gmail.com> Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20230606181714.532998-1-jolsa@kernel.org
2023-06-03Merge tag 'probes-fixes-6.4-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - Return NULL if the trace_probe list on trace_probe_event is empty - selftests/ftrace: Choose testing symbol name for filtering feature from sample data instead of fixed symbol * tag 'probes-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/ftrace: Choose target function for filter test from samples tracing/probe: trace_probe_primary_from_call(): checked list_first_entry
2023-05-31tracing/probe: trace_probe_primary_from_call(): checked list_first_entryPietro Borrello
All callers of trace_probe_primary_from_call() check the return value to be non NULL. However, the function returns list_first_entry(&tpe->probes, ...) which can never be NULL. Additionally, it does not check for the list being possibly empty, possibly causing a type confusion on empty lists. Use list_first_entry_or_null() which solves both problems. Link: https://lore.kernel.org/linux-trace-kernel/20230128-list-entry-null-check-v1-1-8bde6a3da2ef@diag.uniroma1.it/ Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-28tracing: Have function_graph selftest call cond_resched()Steven Rostedt (Google)
When all kernel debugging is enabled (lockdep, KSAN, etc), the function graph enabling and disabling can take several seconds to complete. The function_graph selftest enables and disables function graph tracing several times. With full debugging enabled, the soft lockup watchdog was triggering because the selftest was running without ever scheduling. Add cond_resched() throughout the test to make sure it does not trigger the soft lockup detector. Link: https://lkml.kernel.org/r/20230528051742.1325503-6-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Only make selftest conditionals affect the global_traceSteven Rostedt (Google)
The tracing_selftest_running and tracing_selftest_disabled variables were to keep trace_printk() and other writes from affecting the tracing selftests, as the tracing selftests would examine the ring buffer to see if it contained what it expected or not. trace_printk() and friends could add to the ring buffer and cause the selftests to fail (and then disable the tracer that was being tested). To keep that from happening, these variables were added and would keep trace_printk() and friends from writing to the ring buffer while the tests were going on. But this was only the top level ring buffer (owned by the global_trace instance). There is no reason to prevent writing into ring buffers of other instances via the trace_array_printk() and friends. For the functions that could be used by other instances, check if the global_trace is the tracer instance that is being written to before deciding to not allow the write. Link: https://lkml.kernel.org/r/20230528051742.1325503-5-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Make tracing_selftest_running/delete nops when not usedSteven Rostedt (Google)
There's no reason to test the condition variables tracing_selftest_running or tracing_selftest_delete when tracing selftests are not enabled. Make them define 0s when not the selftests are not configured in. Link: https://lkml.kernel.org/r/20230528051742.1325503-4-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Have tracer selftests call cond_resched() before runningSteven Rostedt (Google)
As there are more and more internal selftests being added to the Linux kernel (KSAN, lockdep, etc) the selftests are taking longer to run when these are enabled. Add a cond_resched() to the calling of do_run_tracer_selftest() to force a schedule if NEED_RESCHED is set, otherwise the soft lockup watchdog may trigger on boot up. Link: https://lkml.kernel.org/r/20230528051742.1325503-3-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-28tracing: Move setting of tracing_selftest_running out of register_tracer()Steven Rostedt (Google)
The variables tracing_selftest_running and tracing_selftest_disabled are only used for when CONFIG_FTRACE_STARTUP_TEST is enabled. Make them only visible within the selftest code. The setting of those variables are in the register_tracer() call, and set in a location where they do not need to be. Create a wrapper around run_tracer_selftest() called do_run_tracer_selftest() which sets those variables, and have register_tracer() call that instead. Having those variables only set within the CONFIG_FTRACE_STARTUP_TEST scope gets rid of them (and also the ability to remove testing against them) when the startup tests are not enabled (most cases). Link: https://lkml.kernel.org/r/20230528051742.1325503-2-rostedt@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing: Rename stacktrace field to common_stacktraceSteven Rostedt (Google)
The histogram and synthetic events can use a pseudo event called "stacktrace" that will create a stacktrace at the time of the event and use it just like it was a normal field. We have other pseudo events such as "common_cpu" and "common_timestamp". To stay consistent with that, convert "stacktrace" to "common_stacktrace". As this was used in older kernels, to keep backward compatibility, this will act just like "common_cpu" did with "cpu". That is, "cpu" will be the same as "common_cpu" unless the event has a "cpu" field. In which case, the event's field is used. The same is true with "stacktrace". Also update the documentation to reflect this change. Link: https://lore.kernel.org/linux-trace-kernel/20230523230913.6860e28d@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/histograms: Allow variables to have some modifiersSteven Rostedt (Google)
Modifiers are used to change the behavior of keys. For instance, they can grouped into buckets, converted to syscall names (from the syscall identifier), show task->comm of the current pid, be an array of longs that represent a stacktrace, and more. It was found that nothing stopped a value from taking a modifier. As values are simple counters. If this happened, it would call code that was not expecting a modifier and crash the kernel. This was fixed by having the ___create_val_field() function test if a modifier was present and fail if one was. This fixed the crash. Now there's a problem with variables. Variables are used to pass fields from one event to another. Variables are allowed to have some modifiers, as the processing may need to happen at the time of the event (like stacktraces and comm names of the current pid). The issue is that it too uses __create_val_field(). Now that fails on modifiers, variables can no longer use them (this is a regression). As not all modifiers are for variables, have them use a separate check. Link: https://lore.kernel.org/linux-trace-kernel/20230523221108.064a5d82@rorschach.local.home Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Fixes: e0213434fe3e4 ("tracing: Do not let histogram values have some modifiers") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/user_events: Document user_event_mm one-shot list usageBeau Belgrave
During 6.4 development it became clear that the one-shot list used by the user_event_mm's next field was confusing to others. It is not clear how this list is protected or what the next field usage is for unless you are familiar with the code. Add comments into the user_event_mm struct indicating lock requirement and usage. Also document how and why this approach was used via comments in both user_event_enabler_update() and user_event_mm_get_all() and the rules to properly use it. Link: https://lkml.kernel.org/r/20230519230741.669-5-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/CAHk-=wicngggxVpbnrYHjRTwGE0WYscPRM+L2HO2BF8ia1EXgQ@mail.gmail.com/ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/user_events: Rename link fields for clarityBeau Belgrave
Currently most list_head fields of various structs within user_events are simply named link. This causes folks to keep additional context in their head when working with the code, which can be confusing. Instead of using link, describe what the actual link is, for example: list_del_rcu(&mm->link); Changes into: list_del_rcu(&mm->mms_link); The reader now is given a hint the link is to the mms global list instead of having to remember or spot check within the code. Link: https://lkml.kernel.org/r/20230519230741.669-4-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/CAHk-=wicngggxVpbnrYHjRTwGE0WYscPRM+L2HO2BF8ia1EXgQ@mail.gmail.com/ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/user_events: Remove RCU lock while pinning pagesLinus Torvalds
pin_user_pages_remote() can reschedule which means we cannot hold any RCU lock while using it. Now that enablers are not exposed out to the tracing register callbacks during fork(), there is clearly no need to require the RCU lock as event_mutex is enough to protect changes. Remove unneeded RCU usages when pinning pages and walking enablers with event_mutex held. Cleanup a misleading "safe" list walk that is not needed. During fork() duplication, remove unneeded RCU list add, since the list is not exposed yet. Link: https://lkml.kernel.org/r/20230519230741.669-3-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/CAHk-=wiiBfT4zNS29jA0XEsy8EmbqTH1hAPdRJCDAJMD8Gxt5A@mail.gmail.com/ Fixes: 7235759084a4 ("tracing/user_events: Use remote writes for event enablement") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [ change log written by Beau Belgrave ] Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/user_events: Split up mm alloc and attachLinus Torvalds
When a new mm is being created in a fork() path it currently is allocated and then attached in one go. This leaves the mm exposed out to the tracing register callbacks while any parent enabler locations are copied in. This should not happen. Split up mm alloc and attach as unique operations. When duplicating enablers, first alloc, then duplicate, and only upon success, attach. This prevents any timing window outside of the event_reg mutex for enablement walking. This allows for dropping RCU requirement for enablement walking in later patches. Link: https://lkml.kernel.org/r/20230519230741.669-2-beaub@linux.microsoft.com Link: https://lore.kernel.org/linux-trace-kernel/CAHk-=whTBvXJuoi_kACo3qi5WZUmRrhyA-_=rRFsycTytmB6qw@mail.gmail.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [ change log written by Beau Belgrave ] Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/timerlat: Always wakeup the timerlat threadDaniel Bristot de Oliveira
While testing rtla timerlat auto analysis, I reach a condition where the interface was not receiving tracing data. I was able to manually reproduce the problem with these steps: # echo 0 > tracing_on # disable trace # echo 1 > osnoise/stop_tracing_us # stop trace if timerlat irq > 1 us # echo timerlat > current_tracer # enable timerlat tracer # sleep 1 # wait... that is the time when rtla # apply configs like prio or cgroup # echo 1 > tracing_on # start tracing # cat trace # tracer: timerlat # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / _-=> migrate-disable # |||| / delay # ||||| ACTIVATION # TASK-PID CPU# ||||| TIMESTAMP ID CONTEXT LATENCY # | | | ||||| | | | | NOTHING! Then, trying to enable tracing again with echo 1 > tracing_on resulted in no change: the trace was still not tracing. This problem happens because the timerlat IRQ hits the stop tracing condition while tracing is off, and do not wake up the timerlat thread, so the timerlat threads are kept sleeping forever, resulting in no trace, even after re-enabling the tracer. Avoid this condition by always waking up the threads, even after stopping tracing, allowing the tracer to return to its normal operating after a new tracing on. Link: https://lore.kernel.org/linux-trace-kernel/1ed8f830638b20a39d535d27d908e319a9a3c4e2.1683822622.git.bristot@kernel.org Cc: Juri Lelli <juri.lelli@redhat.com> Cc: stable@vger.kernel.org Fixes: a955d7eac177 ("trace: Add timerlat tracer") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/user_events: Use long vs int for atomic bit opsBeau Belgrave
Each event stores a int to track which bit to set/clear when enablement changes. On big endian 64-bit configurations, it's possible this could cause memory corruption when it's used for atomic bit operations. Use unsigned long for enablement values to ensure any possible corruption cannot occur. Downcast to int after mask for the bit target. Link: https://lore.kernel.org/all/6f758683-4e5e-41c3-9b05-9efc703e827c@kili.mountain/ Link: https://lore.kernel.org/linux-trace-kernel/20230505205855.6407-1-beaub@linux.microsoft.com Fixes: dcb8177c1395 ("tracing/user_events: Add ioctl for disabling addresses") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-18fprobe: add recursion detection in fprobe_exit_handlerZe Gao
fprobe_hander and fprobe_kprobe_handler has guarded ftrace recursion detection but fprobe_exit_handler has not, which possibly introduce recursive calls if the fprobe exit callback calls any traceable functions. Checking in fprobe_hander or fprobe_kprobe_handler is not enough and misses this case. So add recursion free guard the same way as fprobe_hander. Since ftrace recursion check does not employ ip(s), so here use entry_ip and entry_parent_ip the same as fprobe_handler. Link: https://lore.kernel.org/all/20230517034510.15639-4-zegao@tencent.com/ Fixes: 5b0ab78998e3 ("fprobe: Add exit_handler support") Signed-off-by: Ze Gao <zegao@tencent.com> Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-18fprobe: make fprobe_kprobe_handler recursion freeZe Gao
Current implementation calls kprobe related functions before doing ftrace recursion check in fprobe_kprobe_handler, which opens door to kernel crash due to stack recursion if preempt_count_{add, sub} is traceable in kprobe_busy_{begin, end}. Things goes like this without this patch quoted from Steven: " fprobe_kprobe_handler() { kprobe_busy_begin() { preempt_disable() { preempt_count_add() { <-- trace fprobe_kprobe_handler() { [ wash, rinse, repeat, CRASH!!! ] " By refactoring the common part out of fprobe_kprobe_handler and fprobe_handler and call ftrace recursion detection at the very beginning, the whole fprobe_kprobe_handler is free from recursion. [ Fix the indentation of __fprobe_handler() parameters. ] Link: https://lore.kernel.org/all/20230517034510.15639-3-zegao@tencent.com/ Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe") Signed-off-by: Ze Gao <zegao@tencent.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-18rethook: use preempt_{disable, enable}_notrace in rethook_trampoline_handlerZe Gao
This patch replaces preempt_{disable, enable} with its corresponding notrace version in rethook_trampoline_handler so no worries about stack recursion or overflow introduced by preempt_count_{add, sub} under fprobe + rethook context. Link: https://lore.kernel.org/all/20230517034510.15639-2-zegao@tencent.com/ Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook") Signed-off-by: Ze Gao <zegao@tencent.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-17tracing: fprobe: Initialize ret valiable to fix smatch errorMasami Hiramatsu (Google)
The commit 39d954200bf6 ("fprobe: Skip exit_handler if entry_handler returns !0") introduced a hidden dependency of 'ret' local variable in the fprobe_handler(), Smatch warns the `ret` can be accessed without initialization. kernel/trace/fprobe.c:59 fprobe_handler() error: uninitialized symbol 'ret'. kernel/trace/fprobe.c 49 fpr->entry_ip = ip; 50 if (fp->entry_data_size) 51 entry_data = fpr->data; 52 } 53 54 if (fp->entry_handler) 55 ret = fp->entry_handler(fp, ip, ftrace_get_regs(fregs), entry_data); ret is only initialized if there is an ->entry_handler 56 57 /* If entry_handler returns !0, nmissed is not counted. */ 58 if (rh) { rh is only true if there is an ->exit_handler. Presumably if you have and ->exit_handler that means you also have a ->entry_handler but Smatch is not smart enough to figure it out. --> 59 if (ret) ^^^ Warning here. 60 rethook_recycle(rh); 61 else 62 rethook_hook(rh, ftrace_get_regs(fregs), true); 63 } 64 out: 65 ftrace_test_recursion_unlock(bit); 66 } Link: https://lore.kernel.org/all/168100731160.79534.374827110083836722.stgit@devnote2/ Reported-by: Dan Carpenter <error27@gmail.com> Link: https://lore.kernel.org/all/85429a5c-a4b9-499e-b6c0-cbd313291c49@kili.mountain Fixes: 39d954200bf6 ("fprobe: Skip exit_handler if entry_handler returns !0") Acked-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-05Merge tag 'trace-v6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull more tracing updates from Steven Rostedt: - Make buffer_percent read/write. The buffer_percent file is how users can state how long to block on the tracing buffer depending on how much is in the buffer. When it hits the "buffer_percent" it will wake the task waiting on the buffer. For some reason it was set to read-only. This was not noticed because testing was done as root without SELinux, but with SELinux it will prevent even root to write to it without having CAP_DAC_OVERRIDE. - The "touched_functions" was added this merge window, but one of the reasons for adding it was not implemented. That was to show what functions were not only touched, but had either a direct trampoline attached to it, or a kprobe or live kernel patching that can "hijack" the function to run a different function. The point is to know if there's functions in the kernel that may not be behaving as the kernel code shows. This can be used for debugging. TODO: Add this information to kernel oops too. * tag 'trace-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attached tracing: Fix permissions for the buffer_percent file
2023-05-05ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attachedSteven Rostedt (Google)
If a function had ever had IPMODIFY or DIRECT attached to it, where this is how live kernel patching and BPF overrides work, mark them and display an "M" in the enabled_functions and touched_functions files. This can be used for debugging. If a function had been modified and later there's a bug in the code related to that function, this can be used to know if the cause is possibly from a live kernel patch or a BPF program that changed the behavior of the code. Also update the documentation on the enabled_functions and touched_functions output, as it was missing direct callers and CALL_OPS. And include this new modify attribute. Link: https://lore.kernel.org/linux-trace-kernel/20230502213233.004e3ae4@gandalf.local.home Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-03tracing: Fix permissions for the buffer_percent fileOndrej Mosnacek
This file defines both read and write operations, yet it is being created as read-only. This means that it can't be written to without the CAP_DAC_OVERRIDE capability. Fix the permissions to allow root to write to it without the need to override DAC perms. Link: https://lore.kernel.org/linux-trace-kernel/20230503140114.3280002-1-omosnace@redhat.com Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 03329f993978 ("tracing: Add tracefs file buffer_percentage") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-28Merge tag 'trace-tools-v6.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing tools updates from Steven Rostedt: - Add auto-analysis only option to rtla/timerlat Add an --aa-only option to the tooling to perform only the auto analysis and not to parse and format the data. - Other minor fixes and clean ups * tag 'trace-tools-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: rtla/timerlat: Fix "Previous IRQ" auto analysis' line rtla/timerlat: Add auto-analysis only option rv: Remove redundant assignment to variable retval rv: Fix addition on an uninitialized variable 'run' rtla: Add .gitignore file
2023-04-28Merge tag 'trace-v6.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - User events are finally ready! After lots of collaboration between various parties, we finally locked down on a stable interface for user events that can also work with user space only tracing. This is implemented by telling the kernel (or user space library, but that part is user space only and not part of this patch set), where the variable is that the application uses to know if something is listening to the trace. There's also an interface to tell the kernel about these events, which will show up in the /sys/kernel/tracing/events/user_events/ directory, where it can be enabled. When it's enabled, the kernel will update the variable, to tell the application to start writing to the kernel. See https://lwn.net/Articles/927595/ - Cleaned up the direct trampolines code to simplify arm64 addition of direct trampolines. Direct trampolines use the ftrace interface but instead of jumping to the ftrace trampoline, applications (mostly BPF) can register their own trampoline for performance reasons. - Some updates to the fprobe infrastructure. fprobes are more efficient than kprobes, as it does not need to save all the registers that kprobes on ftrace do. More work needs to be done before the fprobes will be exposed as dynamic events. - More updates to references to the obsolete path of /sys/kernel/debug/tracing for the new /sys/kernel/tracing path. - Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer line by line instead of all at once. There are users in production kernels that have a large data dump that originally used printk() directly, but the data dump was larger than what printk() allowed as a single print. Using seq_buf() to do the printing fixes that. - Add /sys/kernel/tracing/touched_functions that shows all functions that was every traced by ftrace or a direct trampoline. This is used for debugging issues where a traced function could have caused a crash by a bpf program or live patching. - Add a "fields" option that is similar to "raw" but outputs the fields of the events. It's easier to read by humans. - Some minor fixes and clean ups. * tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (41 commits) ring-buffer: Sync IRQ works before buffer destruction tracing: Add missing spaces in trace_print_hex_seq() ring-buffer: Ensure proper resetting of atomic variables in ring_buffer_reset_online_cpus recordmcount: Fix memory leaks in the uwrite function tracing/user_events: Limit max fault-in attempts tracing/user_events: Prevent same address and bit per process tracing/user_events: Ensure bit is cleared on unregister tracing/user_events: Ensure write index cannot be negative seq_buf: Add seq_buf_do_printk() helper tracing: Fix print_fields() for __dyn_loc/__rel_loc tracing/user_events: Set event filter_type from type ring-buffer: Clearly check null ptr returned by rb_set_head_page() tracing: Unbreak user events tracing/user_events: Use print_format_fields() for trace output tracing/user_events: Align structs with tabs for readability tracing/user_events: Limit global user_event count tracing/user_events: Charge event allocs to cgroups tracing/user_events: Update documentation for ABI tracing/user_events: Use write ABI in example tracing/user_events: Add ABI self-test ...
2023-04-27Merge tag 'modules-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...
2023-04-27ring-buffer: Sync IRQ works before buffer destructionJohannes Berg
If something was written to the buffer just before destruction, it may be possible (maybe not in a real system, but it did happen in ARCH=um with time-travel) to destroy the ringbuffer before the IRQ work ran, leading this KASAN report (or a crash without KASAN): BUG: KASAN: slab-use-after-free in irq_work_run_list+0x11a/0x13a Read of size 8 at addr 000000006d640a48 by task swapper/0 CPU: 0 PID: 0 Comm: swapper Tainted: G W O 6.3.0-rc1 #7 Stack: 60c4f20f 0c203d48 41b58ab3 60f224fc 600477fa 60f35687 60c4f20f 601273dd 00000008 6101eb00 6101eab0 615be548 Call Trace: [<60047a58>] show_stack+0x25e/0x282 [<60c609e0>] dump_stack_lvl+0x96/0xfd [<60c50d4c>] print_report+0x1a7/0x5a8 [<603078d3>] kasan_report+0xc1/0xe9 [<60308950>] __asan_report_load8_noabort+0x1b/0x1d [<60232844>] irq_work_run_list+0x11a/0x13a [<602328b4>] irq_work_tick+0x24/0x34 [<6017f9dc>] update_process_times+0x162/0x196 [<6019f335>] tick_sched_handle+0x1a4/0x1c3 [<6019fd9e>] tick_sched_timer+0x79/0x10c [<601812b9>] __hrtimer_run_queues.constprop.0+0x425/0x695 [<60182913>] hrtimer_interrupt+0x16c/0x2c4 [<600486a3>] um_timer+0x164/0x183 [...] Allocated by task 411: save_stack_trace+0x99/0xb5 stack_trace_save+0x81/0x9b kasan_save_stack+0x2d/0x54 kasan_set_track+0x34/0x3e kasan_save_alloc_info+0x25/0x28 ____kasan_kmalloc+0x8b/0x97 __kasan_kmalloc+0x10/0x12 __kmalloc+0xb2/0xe8 load_elf_phdrs+0xee/0x182 [...] The buggy address belongs to the object at 000000006d640800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 584 bytes inside of freed 1024-byte region [000000006d640800, 000000006d640c00) Add the appropriate irq_work_sync() so the work finishes before the buffers are destroyed. Prior to the commit in the Fixes tag below, there was only a single global IRQ work, so this issue didn't exist. Link: https://lore.kernel.org/linux-trace-kernel/20230427175920.a76159263122.I8295e405c44362a86c995e9c2c37e3e03810aa56@changeid Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 15693458c4bc ("tracing/ring-buffer: Move poll wake ups into ring buffer code") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-26Merge tag 'net-next-6.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "Core: - Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the default value allows for better BIG TCP performances - Reduce compound page head access for zero-copy data transfers - RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when possible - Threaded NAPI improvements, adding defer skb free support and unneeded softirq avoidance - Address dst_entry reference count scalability issues, via false sharing avoidance and optimize refcount tracking - Add lockless accesses annotation to sk_err[_soft] - Optimize again the skb struct layout - Extends the skb drop reasons to make it usable by multiple subsystems - Better const qualifier awareness for socket casts BPF: - Add skb and XDP typed dynptrs which allow BPF programs for more ergonomic and less brittle iteration through data and variable-sized accesses - Add a new BPF netfilter program type and minimal support to hook BPF programs to netfilter hooks such as prerouting or forward - Add more precise memory usage reporting for all BPF map types - Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params - Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton - Bigger batch of BPF verifier improvements to prepare for upcoming BPF open-coded iterators allowing for less restrictive looping capabilities - Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF programs to NULL-check before passing such pointers into kfunc - Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in local storage maps - Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps - Add support for refcounted local kptrs to the verifier for allowing shared ownership, useful for adding a node to both the BPF list and rbtree - Add BPF verifier support for ST instructions in convert_ctx_access() which will help new -mcpu=v4 clang flag to start emitting them - Add ARM32 USDT support to libbpf - Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations Protocols: - IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value indicates the provenance of the IP address - IPv6: optimize route lookup, dropping unneeded R/W lock acquisition - Add the handshake upcall mechanism, allowing the user-space to implement generic TLS handshake on kernel's behalf - Bridge: support per-{Port, VLAN} neighbor suppression, increasing resilience to nodes failures - SCTP: add support for Fair Capacity and Weighted Fair Queueing schedulers - MPTCP: delay first subflow allocation up to its first usage. This will allow for later better LSM interaction - xfrm: Remove inner/outer modes from input/output path. These are not needed anymore - WiFi: - reduced neighbor report (RNR) handling for AP mode - HW timestamping support - support for randomized auth/deauth TA for PASN privacy - per-link debugfs for multi-link - TC offload support for mac80211 drivers - mac80211 mesh fast-xmit and fast-rx support - enable Wi-Fi 7 (EHT) mesh support Netfilter: - Add nf_tables 'brouting' support, to force a packet to be routed instead of being bridged - Update bridge netfilter and ovs conntrack helpers to handle IPv6 Jumbo packets properly, i.e. fetch the packet length from hop-by-hop extension header. This is needed for BIT TCP support - The iptables 32bit compat interface isn't compiled in by default anymore - Move ip(6)tables builtin icmp matches to the udptcp one. This has the advantage that icmp/icmpv6 match doesn't load the iptables/ip6tables modules anymore when iptables-nft is used - Extended netlink error report for netdevice in flowtables and netdev/chains. Allow for incrementally add/delete devices to netdev basechain. Allow to create netdev chain without device Driver API: - Remove redundant Device Control Error Reporting Enable, as PCI core has already error reporting enabled at enumeration time - Move Multicast DB netlink handlers to core, allowing devices other then bridge to use them - Allow the page_pool to directly recycle the pages from safely localized NAPI - Implement lockless TX queue stop/wake combo macros, allowing for further code de-duplication and sanitization - Add YNL support for user headers and struct attrs - Add partial YNL specification for devlink - Add partial YNL specification for ethtool - Add tc-mqprio and tc-taprio support for preemptible traffic classes - Add tx push buf len param to ethtool, specifies the maximum number of bytes of a transmitted packet a driver can push directly to the underlying device - Add basic LED support for switch/phy - Add NAPI documentation, stop relaying on external links - Convert dsa_master_ioctl() to netdev notifier. This is a preparatory work to make the hardware timestamping layer selectable by user space - Add transceiver support and improve the error messages for CAN-FD controllers New hardware / drivers: - Ethernet: - AMD/Pensando core device support - MediaTek MT7981 SoC - MediaTek MT7988 SoC - Broadcom BCM53134 embedded switch - Texas Instruments CPSW9G ethernet switch - Qualcomm EMAC3 DWMAC ethernet - StarFive JH7110 SoC - NXP CBTX ethernet PHY - WiFi: - Apple M1 Pro/Max devices - RealTek rtl8710bu/rtl8188gu - RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset - Bluetooth: - Realtek RTL8821CS, RTL8851B, RTL8852BS - Mediatek MT7663, MT7922 - NXP w8997 - Actions Semi ATS2851 - QTI WCN6855 - Marvell 88W8997 - Can: - STMicroelectronics bxcan stm32f429 Drivers: - Ethernet NICs: - Intel (1G, icg): - add tracking and reporting of QBV config errors - add support for configuring max SDU for each Tx queue - Intel (100G, ice): - refactor mailbox overflow detection to support Scalable IOV - GNSS interface optimization - Intel (i40e): - support XDP multi-buffer - nVidia/Mellanox: - add the support for linux bridge multicast offload - enable TC offload for egress and engress MACVLAN over bond - add support for VxLAN GBP encap/decap flows offload - extend packet offload to fully support libreswan - support tunnel mode in mlx5 IPsec packet offload - extend XDP multi-buffer support - support MACsec VLAN offload - add support for dynamic msix vectors allocation - drop RX page_cache and fully use page_pool - implement thermal zone to report NIC temperature - Netronome/Corigine: - add support for multi-zone conntrack offload - Solarflare/Xilinx: - support offloading TC VLAN push/pop actions to the MAE - support TC decap rules - support unicast PTP - Other NICs: - Broadcom (bnxt): enforce software based freq adjustments only on shared PHC NIC - RealTek (r8169): refactor to addess ASPM issues during NAPI poll - Micrel (lan8841): add support for PTP_PF_PEROUT - Cadence (macb): enable PTP unicast - Engleder (tsnep): add XDP socket zero-copy support - virtio-net: implement exact header length guest feature - veth: add page_pool support for page recycling - vxlan: add MDB data path support - gve: add XDP support for GQI-QPL format - geneve: accept every ethertype - macvlan: allow some packets to bypass broadcast queue - mana: add support for jumbo frame - Ethernet high-speed switches: - Microchip (sparx5): Add support for TC flower templates - Ethernet embedded switches: - Broadcom (b54): - configure 6318 and 63268 RGMII ports - Marvell (mv88e6xxx): - faster C45 bus scan - Microchip: - lan966x: - add support for IS1 VCAP - better TX/RX from/to CPU performances - ksz9477: add ETS Qdisc support - ksz8: enhance static MAC table operations and error handling - sama7g5: add PTP capability - NXP (ocelot): - add support for external ports - add support for preemptible traffic classes - Texas Instruments: - add CPSWxG SGMII support for J7200 and J721E - Intel WiFi (iwlwifi): - preparation for Wi-Fi 7 EHT and multi-link support - EHT (Wi-Fi 7) sniffer support - hardware timestamping support for some devices/firwmares - TX beacon protection on newer hardware - Qualcomm 802.11ax WiFi (ath11k): - MU-MIMO parameters support - ack signal support for management packets - RealTek WiFi (rtw88): - SDIO bus support - better support for some SDIO devices (e.g. MAC address from efuse) - RealTek WiFi (rtw89): - HW scan support for 8852b - better support for 6 GHz scanning - support for various newer firmware APIs - framework firmware backwards compatibility - MediaTek WiFi (mt76): - P2P support - mesh A-MSDU support - EHT (Wi-Fi 7) support - coredump support" * tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2078 commits) net: phy: hide the PHYLIB_LEDS knob net: phy: marvell-88x2222: remove unnecessary (void*) conversions tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp. net: amd: Fix link leak when verifying config failed net: phy: marvell: Fix inconsistent indenting in led_blink_set lan966x: Don't use xdp_frame when action is XDP_TX tsnep: Add XDP socket zero-copy TX support tsnep: Add XDP socket zero-copy RX support tsnep: Move skb receive action to separate function tsnep: Add functions for queue enable/disable tsnep: Rework TX/RX queue initialization tsnep: Replace modulo operation with mask net: phy: dp83867: Add led_brightness_set support net: phy: Fix reading LED reg property drivers: nfc: nfcsim: remove return value check of `dev_dir` net: phy: dp83867: Remove unnecessary (void*) conversions net: ethtool: coalesce: try to make user settings stick twice net: mana: Check if netdev/napi_alloc_frag returns single page net: mana: Rename mana_refill_rxoob and remove some empty lines net: veth: add page_pool stats ...
2023-04-26tracing: Add missing spaces in trace_print_hex_seq()Ken Lin
If the buffer length is larger than 16 and concatenate is set to false, there would be missing spaces every 16 bytes. Example: Before: c5 11 10 50 05 4d 31 40 00 40 00 40 00 4d 31 4000 40 00 After: c5 11 10 50 05 4d 31 40 00 40 00 40 00 4d 31 40 00 40 00 Link: https://lore.kernel.org/linux-trace-kernel/20230426032257.3157247-1-lyenting@google.com Signed-off-by: Ken Lin <lyenting@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-26ring-buffer: Ensure proper resetting of atomic variables in ↵Tze-nan Wu
ring_buffer_reset_online_cpus In ring_buffer_reset_online_cpus, the buffer_size_kb write operation may permanently fail if the cpu_online_mask changes between two for_each_online_buffer_cpu loops. The number of increases and decreases on both cpu_buffer->resize_disabled and cpu_buffer->record_disabled may be inconsistent, causing some CPUs to have non-zero values for these atomic variables after the function returns. This issue can be reproduced by "echo 0 > trace" while hotplugging cpu. After reproducing success, we can find out buffer_size_kb will not be functional anymore. To prevent leaving 'resize_disabled' and 'record_disabled' non-zero after ring_buffer_reset_online_cpus returns, we ensure that each atomic variable has been set up before atomic_sub() to it. Link: https://lore.kernel.org/linux-trace-kernel/20230426062027.17451-1-Tze-nan.Wu@mediatek.com Cc: stable@vger.kernel.org Cc: <mhiramat@kernel.org> Cc: npiggin@gmail.com Fixes: b23d7a5f4a07 ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU") Reviewed-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com> Signed-off-by: Tze-nan Wu <Tze-nan.Wu@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing/user_events: Limit max fault-in attemptsBeau Belgrave
When event enablement changes, user_events attempts to update a bit in the user process. If a fault is hit, an attempt to fault-in the page and the write is retried if the page made it in. While this normally requires a couple attempts, it is possible a bad user process could attempt to cause infinite loops. Ensure fault-in attempts either sync or async are limited to a max of 10 attempts for each update. When the max is hit, return -EFAULT so another attempt is not made in all cases. Link: https://lkml.kernel.org/r/20230425225107.8525-5-beaub@linux.microsoft.com Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing/user_events: Prevent same address and bit per processBeau Belgrave
User processes register an address and bit pair for events. If the same address and bit pair are registered multiple times in the same process, it can cause undefined behavior when events are enabled/disabled. When more than one are used, the bit could be turned off by another event being disabled, while the original event is still enabled. Prevent undefined behavior by checking the current mm to see if any event has already been registered for the address and bit pair. Return EADDRINUSE back to the user process if it's already being used. Update ftrace self-test to ensure this occurs properly. Link: https://lkml.kernel.org/r/20230425225107.8525-4-beaub@linux.microsoft.com Suggested-by: Doug Cook <dcook@linux.microsoft.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing/user_events: Ensure bit is cleared on unregisterBeau Belgrave
If an event is enabled and a user process unregisters user_events, the bit is left set. Fix this by always clearing the bit in the user process if unregister is successful. Update abi self-test to ensure this occurs properly. Link: https://lkml.kernel.org/r/20230425225107.8525-3-beaub@linux.microsoft.com Suggested-by: Doug Cook <dcook@linux.microsoft.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing/user_events: Ensure write index cannot be negativeBeau Belgrave
The write index indicates which event the data is for and accesses a per-file array. The index is passed by user processes during write() calls as the first 4 bytes. Ensure that it cannot be negative by returning -EINVAL to prevent out of bounds accesses. Update ftrace self-test to ensure this occurs properly. Link: https://lkml.kernel.org/r/20230425225107.8525-2-beaub@linux.microsoft.com Fixes: 7f5a08c79df3 ("user_events: Add minimal support for trace_event into ftrace") Reported-by: Doug Cook <dcook@linux.microsoft.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing: Fix print_fields() for __dyn_loc/__rel_locBeau Belgrave
Both print_fields() and print_array() do not handle if dynamic data ends at the last byte of the payload for both __dyn_loc and __rel_loc field types. For __rel_loc, the offset was off by 4 bytes, leading to incorrect strings and data being printed out. In print_array() the buffer pos was missed from being advanced, which results in the first payload byte being used as the offset base instead of the field offset. Advance __rel_loc offset by 4 to ensure correct offset and advance pos to the field offset to ensure correct data is displayed when printing arrays. Change >= to > when checking if data is in-bounds, since it's valid for dynamic data to include the last byte of the payload. Example outputs for event format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:__rel_loc char text[]; offset:8; size:4; signed:1; Output before: tp_rel_loc: text=<OVERFLOW> Output after: tp_rel_loc: text=Test Link: https://lkml.kernel.org/r/20230419214140.4158-3-beaub@linux.microsoft.com Fixes: 80a76994b2d8 ("tracing: Add "fields" option to show raw trace event fields") Reported-by: Doug Cook <dcook@linux.microsoft.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25tracing/user_events: Set event filter_type from typeBeau Belgrave
Users expect that events can be filtered by the kernel. User events currently sets all event fields as FILTER_OTHER which limits to binary filters only. When strings are being used, functionality is reduced. Use filter_assign_type() to find the most appropriate filter type for each field in user events to ensure full kernel capabilities. Link: https://lkml.kernel.org/r/20230419214140.4158-2-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25ring-buffer: Clearly check null ptr returned by rb_set_head_page()Zheng Yejian
In error case, 'buffer_page' returned by rb_set_head_page() is NULL, currently check '&buffer_page->list' is equivalent to check 'buffer_page' due to 'list' is the first member of 'buffer_page', but suppose it is not some time, 'head_page' would be wild memory while check would be bypassed. Link: https://lore.kernel.org/linux-trace-kernel/20230414071729.57312-1-zhengyejian1@huawei.com Cc: <mhiramat@kernel.org> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25rv: Remove redundant assignment to variable retvalColin Ian King
Variable retval is being assigned a value that is never read, it is being re-assigned a new value in both paths of a following if statement. Remove the assignment. Cleans up clang-scan warning: kernel/trace/rv/rv.c:293:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores] retval = count; Link: https://lkml.kernel.org/r/20230418150018.3123753-1-colin.i.king@gmail.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "ACPI: - Improve error reporting when failing to manage SDEI on AGDI device removal Assembly routines: - Improve register constraints so that the compiler can make use of the zero register instead of moving an immediate #0 into a GPR - Allow the compiler to allocate the registers used for CAS instructions CPU features and system registers: - Cleanups to the way in which CPU features are identified from the ID register fields - Extend system register definition generation to handle Enum types when defining shared register fields - Generate definitions for new _EL2 registers and add new fields for ID_AA64PFR1_EL1 - Allow SVE to be disabled separately from SME on the kernel command-line Tracing: - Support for "direct calls" in ftrace, which enables BPF tracing for arm64 Kdump: - Don't bother unmapping the crashkernel from the linear mapping, which then allows us to use huge (block) mappings and reduce TLB pressure when a crashkernel is loaded. Memory management: - Try again to remove data cache invalidation from the coherent DMA allocation path - Simplify the fixmap code by mapping at page granularity - Allow the kfence pool to be allocated early, preventing the rest of the linear mapping from being forced to page granularity Perf and PMU: - Move CPU PMU code out to drivers/perf/ where it can be reused by the 32-bit ARM architecture when running on ARMv8 CPUs - Fix race between CPU PMU probing and pKVM host de-privilege - Add support for Apple M2 CPU PMU - Adjust the generic PERF_COUNT_HW_BRANCH_INSTRUCTIONS event dynamically, depending on what the CPU actually supports - Minor fixes and cleanups to system PMU drivers Stack tracing: - Use the XPACLRI instruction to strip PAC from pointers, rather than rolling our own function in C - Remove redundant PAC removal for toolchains that handle this in their builtins - Make backtracing more resilient in the face of instrumentation Miscellaneous: - Fix single-step with KGDB - Remove harmless warning when 'nokaslr' is passed on the kernel command-line - Minor fixes and cleanups across the board" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (72 commits) KVM: arm64: Ensure CPU PMU probes before pKVM host de-privilege arm64: kexec: include reboot.h arm64: delete dead code in this_cpu_set_vectors() arm64/cpufeature: Use helper macro to specify ID register for capabilites drivers/perf: hisi: add NULL check for name drivers/perf: hisi: Remove redundant initialized of pmu->name arm64/cpufeature: Consistently use symbolic constants for min_field_value arm64/cpufeature: Pull out helper for CPUID register definitions arm64/sysreg: Convert HFGITR_EL2 to automatic generation ACPI: AGDI: Improve error reporting for problems during .remove() arm64: kernel: Fix kernel warning when nokaslr is passed to commandline perf/arm-cmn: Fix port detection for CMN-700 arm64: kgdb: Set PSTATE.SS to 1 to re-enable single-step arm64: move PAC masks to <asm/pointer_auth.h> arm64: use XPACLRI to strip PAC arm64: avoid redundant PAC stripping in __builtin_return_address() arm64/sme: Fix some comments of ARM SME arm64/signal: Alloc tpidr2 sigframe after checking system_supports_tpidr2() arm64/signal: Use system_supports_tpidr2() to check TPIDR2 arm64/idreg: Don't disable SME when disabling SVE ...