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2021-02-23Merge tag 'modules-for-v5.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: - Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These export types were introduced between 2006 - 2008. All the of the unused symbols have been long removed and gpl future symbols were converted to gpl quite a long time ago, and I don't believe these export types have been used ever since. So, I think it should be safe to retire those export types now (Christoph Hellwig) - Refactor and clean up some aged code cruft in the module loader (Christoph Hellwig) - Build {,module_}kallsyms_on_each_symbol only when livepatching is enabled, as it is the only caller (Christoph Hellwig) - Unexport find_module() and module_mutex and fix the last module callers to not rely on these anymore. Make module_mutex internal to the module loader (Christoph Hellwig) - Harden ELF checks on module load and validate ELF structures before checking the module signature (Frank van der Linden) - Fix undefined symbol warning for clang (Fangrui Song) - Fix smatch warning (Dan Carpenter) * tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: potential uninitialized return in module_kallsyms_on_each_symbol() module: remove EXPORT_UNUSED_SYMBOL* module: remove EXPORT_SYMBOL_GPL_FUTURE module: move struct symsearch to module.c module: pass struct find_symbol_args to find_symbol module: merge each_symbol_section into find_symbol module: remove each_symbol_in_section module: mark module_mutex static kallsyms: only build {,module_}kallsyms_on_each_symbol when required kallsyms: refactor {,module_}kallsyms_on_each_symbol module: use RCU to synchronize find_module module: unexport find_module and module_mutex drm: remove drm_fb_helper_modinit powerpc/powernv: remove get_cxl_module module: harden ELF info handling module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
2021-02-09tracing/dynevent: Delegate parsing to create functionMasami Hiramatsu
Delegate command parsing to each create function so that the command syntax can be customized. This requires changes to the kprobe/uprobe/synthetic event handling, which are also included here. Link: https://lkml.kernel.org/r/e488726f49cbdbc01568618f8680584306c4c79f.1612208610.git.zanussi@kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ zanussi@kernel.org: added synthetic event modifications ] Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-08module: use RCU to synchronize find_moduleChristoph Hellwig
Allow for a RCU-sched critical section around find_module, following the lower level find_module_all helper, and switch the two callers outside of module.c to use such a RCU-sched critical section instead of module_mutex. Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-02tracing: Merge irqflags + preempt counter.Sebastian Andrzej Siewior
The state of the interrupts (irqflags) and the preemption counter are both passed down to tracing_generic_entry_update(). Only one bit of irqflags is actually required: The on/off state. The complete 32bit of the preemption counter isn't needed. Just whether of the upper bits (softirq, hardirq and NMI) are set and the preemption depth is needed. The irqflags and the preemption counter could be evaluated early and the information stored in an integer `trace_ctx'. tracing_generic_entry_update() would use the upper bits as the TRACE_FLAG_* and the lower 8bit as the disabled-preemption depth (considering that one must be substracted from the counter in one special cases). The actual preemption value is not used except for the tracing record. The `irqflags' variable is mostly used only for the tracing record. An exception here is for instance wakeup_tracer_call() or probe_wakeup_sched_switch() which explicilty disable interrupts and use that `irqflags' to save (and restore) the IRQ state and to record the state. Struct trace_event_buffer has also the `pc' and flags' members which can be replaced with `trace_ctx' since their actual value is not used outside of trace recording. This will reduce tracing_generic_entry_update() to simply assign values to struct trace_entry. The evaluation of the TRACE_FLAG_* bits is moved to _tracing_gen_ctx_flags() which replaces preempt_count() and local_save_flags() invocations. As an example, ftrace_syscall_enter() may invoke: - trace_buffer_lock_reserve() -> … -> tracing_generic_entry_update() - event_trigger_unlock_commit() -> ftrace_trace_stack() -> … -> tracing_generic_entry_update() -> ftrace_trace_userstack() -> … -> tracing_generic_entry_update() In this case the TRACE_FLAG_* bits were evaluated three times. By using the `trace_ctx' they are evaluated once and assigned three times. A build with all tracers enabled on x86-64 with and without the patch: text data bss dec hex filename 21970669 17084168 7639260 46694097 2c87ed1 vmlinux.old 21970293 17084168 7639260 46693721 2c87d59 vmlinux.new text shrank by 379 bytes, data remained constant. Link: https://lkml.kernel.org/r/20210125194511.3924915-2-bigeasy@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-29tracing/kprobe: Fix to support kretprobe events on unloaded modulesMasami Hiramatsu
Fix kprobe_on_func_entry() returns error code instead of false so that register_kretprobe() can return an appropriate error code. append_trace_kprobe() expects the kprobe registration returns -ENOENT when the target symbol is not found, and it checks whether the target module is unloaded or not. If the target module doesn't exist, it defers to probe the target symbol until the module is loaded. However, since register_kretprobe() returns -EINVAL instead of -ENOENT in that case, it always fail on putting the kretprobe event on unloaded modules. e.g. Kprobe event: /sys/kernel/debug/tracing # echo p xfs:xfs_end_io >> kprobe_events [ 16.515574] trace_kprobe: This probe might be able to register after target module is loaded. Continue. Kretprobe event: (p -> r) /sys/kernel/debug/tracing # echo r xfs:xfs_end_io >> kprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # cat error_log [ 41.122514] trace_kprobe: error: Failed to register probe event Command: r xfs:xfs_end_io ^ To fix this bug, change kprobe_on_func_entry() to detect symbol lookup failure and return -ENOENT in that case. Otherwise it returns -EINVAL or 0 (succeeded, given address is on the entry). Link: https://lkml.kernel.org/r/161176187132.1067016.8118042342894378981.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 59158ec4aef7 ("tracing/kprobes: Check the probe on unloaded module correctly") Reported-by: Jianlin Lv <Jianlin.Lv@arm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-11tracing/kprobes: Do the notrace functions check without kprobes on ftraceMasami Hiramatsu
Enable the notrace function check on the architecture which doesn't support kprobes on ftrace but support dynamic ftrace. This notrace function check is not only for the kprobes on ftrace but also sw-breakpoint based kprobes. Thus there is no reason to limit this check for the arch which supports kprobes on ftrace. This also changes the dependency of Kconfig. Because kprobe event uses the function tracer's address list for identifying notrace function, if the CONFIG_DYNAMIC_FTRACE=n, it can not check whether the target function is notrace or not. Link: https://lkml.kernel.org/r/20210105065730.2634785-1-naveen.n.rao@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/161007957862.114704.4512260007555399463.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 45408c4f92506 ("tracing: kprobes: Prohibit probing on notrace function") Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-12-17Merge tag 'trace-v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The major update to this release is that there's a new arch config option called CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS. Currently, only x86_64 enables it. All the ftrace callbacks now take a struct ftrace_regs instead of a struct pt_regs. If the architecture has HAVE_DYNAMIC_FTRACE_WITH_ARGS enabled, then the ftrace_regs will have enough information to read the arguments of the function being traced, as well as access to the stack pointer. This way, if a user (like live kernel patching) only cares about the arguments, then it can avoid using the heavier weight "regs" callback, that puts in enough information in the struct ftrace_regs to simulate a breakpoint exception (needed for kprobes). A new config option that audits the timestamps of the ftrace ring buffer at most every event recorded. Ftrace recursion protection has been cleaned up to move the protection to the callback itself (this saves on an extra function call for those callbacks). Perf now handles its own RCU protection and does not depend on ftrace to do it for it (saving on that extra function call). New debug option to add "recursed_functions" file to tracefs that lists all the places that triggered the recursion protection of the function tracer. This will show where things need to be fixed as recursion slows down the function tracer. The eval enum mapping updates done at boot up are now offloaded to a work queue, as it caused a noticeable pause on slow embedded boards. Various clean ups and last minute fixes" * tag 'trace-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) tracing: Offload eval map updates to a work queue Revert: "ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS" ring-buffer: Add rb_check_bpage in __rb_allocate_pages ring-buffer: Fix two typos in comments tracing: Drop unneeded assignment in ring_buffer_resize() tracing: Disable ftrace selftests when any tracer is running seq_buf: Avoid type mismatch for seq_buf_init ring-buffer: Fix a typo in function description ring-buffer: Remove obsolete rb_event_is_commit() ring-buffer: Add test to validate the time stamp deltas ftrace/documentation: Fix RST C code blocks tracing: Clean up after filter logic rewriting tracing: Remove the useless value assignment in test_create_synth_event() livepatch: Use the default ftrace_ops instead of REGS when ARGS is available ftrace/x86: Allow for arguments to be passed in to ftrace_regs by default ftrace: Have the callbacks receive a struct ftrace_regs instead of pt_regs MAINTAINERS: assign ./fs/tracefs to TRACING tracing: Fix some typos in comments ftrace: Remove unused varible 'ret' ring-buffer: Add recording of ring buffer recursion into recursed_functions ...
2020-12-14tracing: Disable ftrace selftests when any tracer is runningMasami Hiramatsu
Disable ftrace selftests when any tracer (kernel command line options like ftrace=, trace_events=, kprobe_events=, and boot-time tracing) starts running because selftest can disturb it. Currently ftrace= and trace_events= are checked, but kprobe_events has a different flag, and boot-time tracing didn't checked. This unifies the disabled flag and all of those boot-time tracing features sets the flag. This also fixes warnings on kprobe-event selftest (CONFIG_FTRACE_STARTUP_TEST=y and CONFIG_KPROBE_EVENTS=y) with boot-time tracing (ftrace.event.kprobes.EVENT.probes) like below; [ 59.803496] trace_kprobe: Testing kprobe tracing: [ 59.804258] ------------[ cut here ]------------ [ 59.805682] WARNING: CPU: 3 PID: 1 at kernel/trace/trace_kprobe.c:1987 kprobe_trace_self_tests_ib [ 59.806944] Modules linked in: [ 59.807335] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7+ #172 [ 59.808029] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/204 [ 59.808999] RIP: 0010:kprobe_trace_self_tests_init+0x5f/0x42b [ 59.809696] Code: e8 03 00 00 48 c7 c7 30 8e 07 82 e8 6d 3c 46 ff 48 c7 c6 00 b2 1a 81 48 c7 c7 7 [ 59.812439] RSP: 0018:ffffc90000013e78 EFLAGS: 00010282 [ 59.813038] RAX: 00000000ffffffef RBX: 0000000000000000 RCX: 0000000000049443 [ 59.813780] RDX: 0000000000049403 RSI: 0000000000049403 RDI: 000000000002deb0 [ 59.814589] RBP: ffffc90000013e90 R08: 0000000000000001 R09: 0000000000000001 [ 59.815349] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000ffffffef [ 59.816138] R13: ffff888004613d80 R14: ffffffff82696940 R15: ffff888004429138 [ 59.816877] FS: 0000000000000000(0000) GS:ffff88807dcc0000(0000) knlGS:0000000000000000 [ 59.817772] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.818395] CR2: 0000000001a8dd38 CR3: 0000000002222000 CR4: 00000000000006a0 [ 59.819144] Call Trace: [ 59.819469] ? init_kprobe_trace+0x6b/0x6b [ 59.819948] do_one_initcall+0x5f/0x300 [ 59.820392] ? rcu_read_lock_sched_held+0x4f/0x80 [ 59.820916] kernel_init_freeable+0x22a/0x271 [ 59.821416] ? rest_init+0x241/0x241 [ 59.821841] kernel_init+0xe/0x10f [ 59.822251] ret_from_fork+0x22/0x30 [ 59.822683] irq event stamp: 16403349 [ 59.823121] hardirqs last enabled at (16403359): [<ffffffff810db81e>] console_unlock+0x48e/0x580 [ 59.824074] hardirqs last disabled at (16403368): [<ffffffff810db786>] console_unlock+0x3f6/0x580 [ 59.825036] softirqs last enabled at (16403200): [<ffffffff81c0033a>] __do_softirq+0x33a/0x484 [ 59.825982] softirqs last disabled at (16403087): [<ffffffff81a00f02>] asm_call_irq_on_stack+0x10 [ 59.827034] ---[ end trace 200c544775cdfeb3 ]--- [ 59.827635] trace_kprobe: error on probing function entry. Link: https://lkml.kernel.org/r/160741764955.3448999.3347769358299456915.stgit@devnote2 Fixes: 4d655281eb1b ("tracing/boot Add kprobe event support") Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-07Merge branch 'linus' into perf/kprobesIngo Molnar
Conflicts: include/asm-generic/atomic-instrumented.h kernel/kprobes.c Use the upstream atomic-instrumented.h checksum, and pick the kprobes version of kernel/kprobes.c, which effectively reverts this upstream workaround: 645f224e7ba2: ("kprobes: Tell lockdep about kprobe nesting") Since the new code *should* be fine without nesting. Knock on wood ... Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-11-07Merge branch 'linus' into perf/kprobesIngo Molnar
Merge recent kprobes updates into perf/kprobes that came from -mm. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-12kprobes: Remove kretprobe hashPeter Zijlstra
The kretprobe hash is mostly superfluous, replace it with a per-task variable. This gets rid of the task hash and it's related locking. Note that this may change the kprobes module-exported API for kretprobe handlers. If any out-of-tree kretprobe user uses ri->rp, use get_kretprobe(ri) instead. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/159870620431.1229682.16325792502413731312.stgit@devnote2
2020-09-21tracing/boot, kprobe, synth: Initialize boot-time tracing earlierMasami Hiramatsu
Initialize boot-time tracing in core_initcall_sync instead of fs_initcall, and initialize required tracers (kprobes and synth) in core_initcall. This will allow the boot-time tracing to trace __init code from the beginning of postcore_initcall stage. Link: https://lkml.kernel.org/r/159974155727.478751.7486926132902849578.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing/kprobes: Support perf-style return probeMasami Hiramatsu
Support perf-style return probe ("SYMBOL%return") for kprobe events. This will allow boot-time tracing user to define a return probe event. Link: https://lkml.kernel.org/r/159972813535.428528.4437029657208468954.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21kprobes: Use module_name() macroJarkko Sakkinen
It is advised to use module_name() macro instead of dereferencing mod->name directly. This makes sense for consistencys sake and also it prevents a hard dependency to CONFIG_MODULES. Link: https://lkml.kernel.org/r/20200818050857.117998-1-jarkko.sakkinen@linux.intel.com Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-mm@kvack.org Cc: Andi Kleen <ak@linux.intel.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com>, Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18tracing: make tracing_init_dentry() returns an integer instead of a d_entry ↵Wei Yang
pointer Current tracing_init_dentry() return a d_entry pointer, while is not necessary. This function returns NULL on success or error on failure, which means there is no valid d_entry pointer return. Let's return 0 on success and negative value for error. Link: https://lkml.kernel.org/r/20200712011036.70948-5-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-17maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofaultChristoph Hellwig
Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofaultChristoph Hellwig
Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix cfg80211 deadlock, from Johannes Berg. 2) RXRPC fails to send norigications, from David Howells. 3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from Geliang Tang. 4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu. 5) The ucc_geth driver needs __netdev_watchdog_up exported, from Valentin Longchamp. 6) Fix hashtable memory leak in dccp, from Wang Hai. 7) Fix how nexthops are marked as FDB nexthops, from David Ahern. 8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni. 9) Fix crashes in tipc_disc_rcv(), from Tuong Lien. 10) Fix link speed reporting in iavf driver, from Brett Creeley. 11) When a channel is used for XSK and then reused again later for XSK, we forget to clear out the relevant data structures in mlx5 which causes all kinds of problems. Fix from Maxim Mikityanskiy. 12) Fix memory leak in genetlink, from Cong Wang. 13) Disallow sockmap attachments to UDP sockets, it simply won't work. From Lorenz Bauer. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits) net: ethernet: ti: ale: fix allmulti for nu type ale net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init net: atm: Remove the error message according to the atomic context bpf: Undo internal BPF_PROBE_MEM in BPF insns dump libbpf: Support pre-initializing .bss global variables tools/bpftool: Fix skeleton codegen bpf: Fix memlock accounting for sock_hash bpf: sockmap: Don't attach programs to UDP sockets bpf: tcp: Recv() should return 0 when the peer socket is closed ibmvnic: Flush existing work items before device removal genetlink: clean up family attributes allocations net: ipa: header pad field only valid for AP->modem endpoint net: ipa: program upper nibbles of sequencer type net: ipa: fix modem LAN RX endpoint id net: ipa: program metadata mask differently ionic: add pcie_print_link_status rxrpc: Fix race between incoming ACK parser and retransmitter net/mlx5: E-Switch, Fix some error pointer dereferences net/mlx5: Don't fail driver on failure to create debugfs net/mlx5e: CT: Fix ipv6 nat header rewrite actions ...
2020-06-09tracing/probe: Fix bpf_task_fd_query() for kprobes and uprobesJean-Philippe Brucker
Commit 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") removed the trace_[ku]probe structure from the trace_event_call->data pointer. As bpf_get_[ku]probe_info() were forgotten in that change, fix them now. These functions are currently only used by the bpf_task_fd_query() syscall handler to collect information about a perf event. Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lore.kernel.org/bpf/20200608124531.819838-1-jean-philippe@linaro.org
2020-06-09maccess: always use strict semantics for probe_kernel_readChristoph Hellwig
Except for historical confusion in the kprobes/uprobes and bpf tracers, which has been fixed now, there is no good reason to ever allow user memory accesses from probe_kernel_read. Switch probe_kernel_read to only read from kernel memory. [akpm@linux-foundation.org: update it for "mm, dump_page(): do not crash with invalid mapping pointer"] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20200521152301.2587579-17-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09tracing/kprobes: handle mixed kernel/userspace probes betterChristoph Hellwig
Instead of using the dangerous probe_kernel_read and strncpy_from_unsafe helpers, rework probes to try a user probe based on the address if the architecture has a common address space for kernel and userspace. [svens@linux.ibm.com:use strncpy_from_kernel_nofault() in fetch_store_string()] Link: http://lkml.kernel.org/r/20200606181903.49384-1-svens@linux.ibm.com Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20200521152301.2587579-15-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09maccess: rename strnlen_unsafe_user to strnlen_user_nofaultChristoph Hellwig
This matches the naming of strnlen_user, and also makes it more clear what the function is supposed to do. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20200521152301.2587579-9-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09maccess: rename strncpy_from_unsafe_user to strncpy_from_user_nofaultChristoph Hellwig
This matches the naming of strncpy_from_user, and also makes it more clear what the function is supposed to do. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20200521152301.2587579-7-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-06tracing/kprobes: Reject new event if loc is NULLMasami Hiramatsu
Reject the new event which has NULL location for kprobes. For kprobes, user must specify at least the location. Link: http://lkml.kernel.org/r/158779376597.6082.1411212055469099461.stgit@devnote2 Cc: Tom Zanussi <zanussi@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Fixes: 2a588dd1d5d6 ("tracing: Add kprobe event command generation functions") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-05-06tracing/kprobes: Fix a double initialization typoMasami Hiramatsu
Fix a typo that resulted in an unnecessary double initialization to addr. Link: http://lkml.kernel.org/r/158779374968.6082.2337484008464939919.stgit@devnote2 Cc: Tom Zanussi <zanussi@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Fixes: c7411a1a126f ("tracing/kprobe: Check whether the non-suffixed symbol is notrace") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace/kprobe: Show the maxactive number on kprobe_eventsMasami Hiramatsu
Show maxactive parameter on kprobe_events. This allows user to save the current configuration and restore it without losing maxactive parameter. Link: http://lkml.kernel.org/r/4762764a-6df7-bc93-ed60-e336146dce1f@gmail.com Link: http://lkml.kernel.org/r/158503528846.22706.5549974121212526020.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 696ced4fb1d76 ("tracing/kprobes: expose maxactive for kretprobe in kprobe_events") Reported-by: Taeung Song <treeze.taeung@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-11Merge tag 'trace-v5.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Various fixes: - Fix an uninitialized variable - Fix compile bug to bootconfig userspace tool (in tools directory) - Suppress some error messages of bootconfig userspace tool - Remove unneded CONFIG_LIBXBC from bootconfig - Allocate bootconfig xbc_nodes dynamically. To ease complaints about taking up static memory at boot up - Use of parse_args() to parse bootconfig instead of strstr() usage Prevents issues of double quotes containing the interested string - Fix missing ring_buffer_nest_end() on synthetic event error path - Return zero not -EINVAL on soft disabled synthetic event (soft disabling must be the same as hard disabling, which returns zero) - Consolidate synthetic event code (remove duplicate code)" * tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Consolidate trace() functions tracing: Don't return -EINVAL when tracing soft disabled synth events tracing: Add missing nest end to synth_event_trace_start() error case tools/bootconfig: Suppress non-error messages bootconfig: Allocate xbc_nodes array dynamically bootconfig: Use parse_args() to find bootconfig and '--' tracing/kprobe: Fix uninitialized variable bug bootconfig: Remove unneeded CONFIG_LIBXBC tools/bootconfig: Fix wrong __VA_ARGS__ usage
2020-02-10tracing/kprobe: Fix uninitialized variable bugGustavo A. R. Silva
There is a potential execution path in which variable *ret* is returned without being properly initialized, previously. Fix this by initializing variable *ret* to 0. Link: http://lkml.kernel.org/r/20200205223404.GA3379@embeddedor Addresses-Coverity-ID: 1491142 ("Uninitialized scalar variable") Fixes: 2a588dd1d5d6 ("tracing: Add kprobe event command generation functions") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-06Merge tag 'trace-v5.6-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Added new "bootconfig". This looks for a file appended to initrd to add boot config options, and has been discussed thoroughly at Linux Plumbers. Very useful for adding kprobes at bootup. Only enabled if "bootconfig" is on the real kernel command line. - Created dynamic event creation. Merges common code between creating synthetic events and kprobe events. - Rename perf "ring_buffer" structure to "perf_buffer" - Rename ftrace "ring_buffer" structure to "trace_buffer" Had to rename existing "trace_buffer" to "array_buffer" - Allow trace_printk() to work withing (some) tracing code. - Sort of tracing configs to be a little better organized - Fixed bug where ftrace_graph hash was not being protected properly - Various other small fixes and clean ups * tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (88 commits) bootconfig: Show the number of nodes on boot message tools/bootconfig: Show the number of bootconfig nodes bootconfig: Add more parse error messages bootconfig: Use bootconfig instead of boot config ftrace: Protect ftrace_graph_hash with ftrace_sync ftrace: Add comment to why rcu_dereference_sched() is open coded tracing: Annotate ftrace_graph_notrace_hash pointer with __rcu tracing: Annotate ftrace_graph_hash pointer with __rcu bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline tracing: Use seq_buf for building dynevent_cmd string tracing: Remove useless code in dynevent_arg_pair_add() tracing: Remove check_arg() callbacks from dynevent args tracing: Consolidate some synth_event_trace code tracing: Fix now invalid var_ref_vals assumption in trace action tracing: Change trace_boot to use synth_event interface tracing: Move tracing selftests to bottom of menu tracing: Move mmio tracer config up with the other tracers tracing: Move tracing test module configs together tracing: Move all function tracing configs together tracing: Documentation for in-kernel synthetic event API ...
2020-02-01tracing: Use seq_buf for building dynevent_cmd stringTom Zanussi
The dynevent_cmd commands that build up the command string don't need to do that themselves - there's a seq_buf facility that does pretty much the same thing those command are doing manually, so use it instead. Link: http://lkml.kernel.org/r/eb8a6e835c964d0ab8a38cbf5ffa60746b54a465.1580506712.git.zanussi@kernel.org Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-01tracing: Remove check_arg() callbacks from dynevent argsTom Zanussi
It's kind of strange to have check_arg() callbacks as part of the arg objects themselves; it makes more sense to just pass these in when the args are added instead. Remove the check_arg() callbacks from those objects which also means removing the check_arg() args from the init functions, adding them to the add functions and fixing up existing callers. Link: http://lkml.kernel.org/r/c7708d6f177fcbe1a36b6e4e8e150907df0fa5d2.1580506712.git.zanussi@kernel.org Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Change trace_boot to use kprobe_event interfaceTom Zanussi
Have trace_boot_add_kprobe_event() use the kprobe_event interface. Also, rename kprobe_event_run_cmd() to kprobe_event_run_command() now that trace_boot's version is gone. Link: http://lkml.kernel.org/r/af5429d11291ab1e9a85a0ff944af3b2bcf193c7.1580323897.git.zanussi@kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Add kprobe event command generation functionsTom Zanussi
Add functions used to generate kprobe event commands, built on top of the dynevent_cmd interface. kprobe_event_gen_cmd_start() is used to create a kprobe event command using a variable arg list, and kretprobe_event_gen_cmd_start() does the same for kretprobe event commands. kprobe_event_add_fields() can be used to add single fields one by one or as a group. Once all desired fields are added, kprobe_event_gen_cmd_end() or kretprobe_event_gen_cmd_end() respectively are used to actually execute the command and create the event. Link: http://lkml.kernel.org/r/95cc4696502bb6017f9126f306a45ad19b4cc14f.1580323897.git.zanussi@kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-28Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Kernel side changes: - Ftrace is one of the last W^X violators (after this only KLP is left). These patches move it over to the generic text_poke() interface and thereby get rid of this oddity. This requires a surprising amount of surgery, by Peter Zijlstra. - x86/AMD PMUs: add support for 'Large Increment per Cycle Events' to count certain types of events that have a special, quirky hw ABI (by Kim Phillips) - kprobes fixes by Masami Hiramatsu Lots of tooling updates as well, the following subcommands were updated: annotate/report/top, c2c, clang, record, report/top TUI, sched timehist, tests; plus updates were done to the gtk ui, libperf, headers and the parser" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) perf/x86/amd: Add support for Large Increment per Cycle Events perf/x86/amd: Constrain Large Increment per Cycle events perf/x86/intel/rapl: Add Comet Lake support tracing: Initialize ret in syscall_enter_define_fields() perf header: Use last modification time for timestamp perf c2c: Fix return type for histogram sorting comparision functions perf beauty sockaddr: Fix augmented syscall format warning perf/ui/gtk: Fix gtk2 build perf ui gtk: Add missing zalloc object perf tools: Use %define api.pure full instead of %pure-parser libperf: Setup initial evlist::all_cpus value perf report: Fix no libunwind compiled warning break s390 issue perf tools: Support --prefix/--prefix-strip perf report: Clarify in help that --children is default tools build: Fix test-clang.cpp with Clang 8+ perf clang: Fix build with Clang 9 kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic tools lib: Fix builds when glibc contains strlcpy() perf report/top: Make 'e' visible in the help and make it toggle showing callchains perf report/top: Do not offer annotation for symbols without samples ...
2020-01-22tracing/uprobe: Fix to make trace_uprobe_filter alignment safeMasami Hiramatsu
Commit 99c9a923e97a ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe") moved trace_uprobe_filter on trace_probe_event. However, since it introduced a flexible data structure with char array and type casting, the alignment of trace_uprobe_filter can be broken. This changes the type of the array to trace_uprobe_filter data strucure to fix it. Link: http://lore.kernel.org/r/20200120124022.GA14897@hirez.programming.kicks-ass.net Link: http://lkml.kernel.org/r/157966340499.5107.10978352478952144902.stgit@devnote2 Fixes: 99c9a923e97a ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe") Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-22trace/kprobe: Remove unused MAX_KPROBE_CMDLINE_SIZEAlex Shi
This limitation are never lunched from introduce commit 970988e19eb0 ("tracing/kprobe: Add kprobe_event= boot parameter") Could we remove it if no intention to implement it? Link: http://lkml.kernel.org/r/1579586075-45132-1-git-send-email-alex.shi@linux.alibaba.com Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-14tracing/uprobe: Fix double perf_event linking on multiprobe uprobeMasami Hiramatsu
Fix double perf_event linking to trace_uprobe_filter on multiple uprobe event by moving trace_uprobe_filter under trace_probe_event. In uprobe perf event, trace_uprobe_filter data structure is managing target mm filters (in perf_event) related to each uprobe event. Since commit 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") left the trace_uprobe_filter data structure in trace_uprobe, if a trace_probe_event has multiple trace_uprobe (multi-probe event), a perf_event is added to different trace_uprobe_filter on each trace_uprobe. This leads a linked list corruption. To fix this issue, move trace_uprobe_filter to trace_probe_event and link it once on each event instead of each probe. Link: http://lkml.kernel.org/r/157862073931.1800.3800576241181489174.stgit@devnote2 Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S . Miller" <davem@davemloft.net> Cc: Namhyung Kim <namhyung@kernel.org> Cc: =?utf-8?q?Toke_H=C3=B8iland-J?= =?utf-8?b?w7hyZ2Vuc2Vu?= <thoiland@redhat.com> Cc: Jean-Tsung Hsiao <jhsiao@redhat.com> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Cc: stable@vger.kernel.org Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Link: https://lkml.kernel.org/r/20200108171611.GA8472@kernel.org Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing/boot Add kprobe event supportMasami Hiramatsu
Add kprobe event support on event node to boot-time tracing. If the group name of event is "kprobes", the boot-time tracing defines new probe event according to "probes" values. - ftrace.event.kprobes.EVENT.probes = PROBE[, PROBE2...] Defines new kprobe event based on PROBEs. It is able to define multiple probes on one event, but those must have same type of arguments. For example, ftrace.events.kprobes.myevent { probes = "vfs_read $arg1 $arg2"; enable; } This will add kprobes:myevent on vfs_read with the 1st and the 2nd arguments. Link: http://lkml.kernel.org/r/157867240104.17873.9712052065426433111.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing: kprobes: Register to dynevent earlier stageMasami Hiramatsu
Register kprobe event to dynevent in subsys_initcall level. This will allow kernel to register new kprobe events in fs_initcall level via trace_run_command. Link: http://lkml.kernel.org/r/157867234213.17873.18039000024374948737.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing: kprobes: Output kprobe event to printk bufferMasami Hiramatsu
Since kprobe-events use event_trigger_unlock_commit_regs() directly, that events doesn't show up in printk buffer if "tp_printk" is set. Use trace_event_buffer_commit() in kprobe events so that it can invoke output_printk() as same as other trace events. Link: http://lkml.kernel.org/r/157867233085.17873.5210928676787339604.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ Adjusted data var declaration placement in __kretprobe_trace_func() ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing: Make struct ring_buffer less ambiguousSteven Rostedt (VMware)
As there's two struct ring_buffers in the kernel, it causes some confusion. The other one being the perf ring buffer. It was agreed upon that as neither of the ring buffers are generic enough to be used globally, they should be renamed as: perf's ring_buffer -> perf_buffer ftrace's ring_buffer -> trace_buffer This implements the changes to the ring buffer that ftrace uses. Link: https://lore.kernel.org/r/20191213140531.116b3200@gandalf.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-12-10Merge tag 'v5.5-rc1' into core/kprobes, to resolve conflictsIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-27ftrace: Rework event_create_dir()Peter Zijlstra
Rework event_create_dir() to use an array of static data instead of function pointers where possible. The problem is that it would call the function pointer on module load before parse_args(), possibly even before jump_labels were initialized. Luckily the generated functions don't use jump_labels but it still seems fragile. It also gets in the way of changing when we make the module map executable. The generated function are basically calling trace_define_field() with a bunch of static arguments. So instead of a function, capture these arguments in a static array, avoiding the function call. Now there are a number of cases where the fields are dynamic (syscall arguments, kprobes and uprobes), in which case a static array does not work, for these we preserve the function call. Luckily all these cases are not related to modules and so we can retain the function call for them. Also fix up all broken tracepoint definitions that now generate a compile error. Tested-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-14tracing/kprobe: Check whether the non-suffixed symbol is notraceMasami Hiramatsu
Check whether the non-suffixed symbol is notrace, since suffixed symbols are generated by the compilers for optimization. Based on these suffixed symbols, notrace check might not work because some of them are just a partial code of the original function. (e.g. cold-cache (unlikely) code is separated from original function as FUNCTION.cold.XX) For example, without this fix, # echo p device_add.cold.67 > /sys/kernel/debug/tracing/kprobe_events sh: write error: Invalid argument # cat /sys/kernel/debug/tracing/error_log [ 135.491035] trace_kprobe: error: Failed to register probe event Command: p device_add.cold.67 ^ # dmesg | tail -n 1 [ 135.488599] trace_kprobe: Could not probe notrace function device_add.cold.67 With this, # echo p device_add.cold.66 > /sys/kernel/debug/tracing/kprobe_events # cat /sys/kernel/debug/kprobes/list ffffffff81599de9 k device_add.cold.66+0x0 [DISABLED] Actually, kprobe blacklist already did similar thing, see within_kprobe_blacklist(). Link: http://lkml.kernel.org/r/157233790394.6706.18243942030937189679.stgit@devnote2 Fixes: 45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Add locked_down checks to the open calls of files created for tracefsSteven Rostedt (VMware)
Added various checks on open tracefs calls to see if tracefs is in lockdown mode, and if so, to return -EPERM. Note, the event format files (which are basically standard on all machines) as well as the enabled_functions file (which shows what is currently being traced) are not lockde down. Perhaps they should be, but it seems counter intuitive to lockdown information to help you know if the system has been modified. Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-28Merge branch 'next-lockdown' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
2019-09-25tracing/probe: Fix same probe event argument matchingSrikar Dronamraju
Commit fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event") tries to reject a event which matches an already existing probe. However it currently continues to match arguments and rejects adding a probe even when the arguments don't match. Fix this by only rejecting a probe if and only if all the arguments match. Link: http://lkml.kernel.org/r/20190924114906.14038-1-srikar@linux.vnet.ibm.com Fixes: fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-19tracing/probe: Reject exactly same probe eventMasami Hiramatsu
Reject exactly same probe events as existing probes. Multiprobe allows user to define multiple probes on same event. If user appends a probe which exactly same definition (same probe address and same arguments) on existing event, the event will record same probe information twice. That can be confusing users, so reject it. Link: http://lkml.kernel.org/r/156879694602.31056.5533024778165036763.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-19tracing/probe: Fix to allow user to enable events on unloaded modulesMasami Hiramatsu
Fix to allow user to enable probe events on unloaded modules. This operations was allowed before commit 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe"), because if users need to probe module init functions, they have to enable those probe events before loading module. Link: http://lkml.kernel.org/r/156879693733.31056.9331322616994665167.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31tracing/probe: Add immediate string parameter supportMasami Hiramatsu
Add immediate string parameter (\"string") support to probe events. This allows you to specify an immediate (or dummy) parameter instead of fetching a string from memory. This feature looks odd, but imagine that you put a probe on a code to trace some string data. If the code is compiled into 2 instructions and 1 instruction has a string on memory but other has no string since it is optimized out. In that case, you can not fold those into one event, even if ftrace supported multiple probes on one event. With this feature, you can set a dummy string like foo=\"(optimized)":string instead of something like foo=+0(+0(%bp)):string. Link: http://lkml.kernel.org/r/156095691687.28024.13372712423865047991.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>