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2020-11-24lib/strncpy_from_user.c: Mask out bytes after NUL terminator.Daniel Xu1-0/+10
[ Upstream commit 6fa6d28051e9fcaa1570e69648ea13a353a5d218 ] do_strncpy_from_user() may copy some extra bytes after the NUL terminator into the destination buffer. This usually does not matter for normal string operations. However, when BPF programs key BPF maps with strings, this matters a lot. A BPF program may read strings from user memory by calling the bpf_probe_read_user_str() helper which eventually calls do_strncpy_from_user(). The program can then key a map with the destination buffer. BPF map keys are fixed-width and string-agnostic, meaning that map keys are treated as a set of bytes. The issue is when do_strncpy_from_user() overcopies bytes after the NUL terminator, it can result in seemingly identical strings occupying multiple slots in a BPF map. This behavior is subtle and totally unexpected by the user. This commit masks out the bytes following the NUL while preserving long-sized stride in the fast path. Fixes: 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers") Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/21efc982b3e9f2f7b0379eed642294caaa0c27a7.1605642949.git.dxu@dxuuu.xyz Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-18tracing: Fix the checking of stackidx in __ftrace_trace_stackQiujun Huang1-2/+2
[ Upstream commit 906695e59324635c62b5ae59df111151a546ca66 ] The array size is FTRACE_KSTACK_NESTING, so the index FTRACE_KSTACK_NESTING is illegal too. And fix two typos by the way. Link: https://lkml.kernel.org/r/20201031085714.2147-1-hqjagain@gmail.com Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10tracing: Fix out of bounds write in get_trace_bufQiujun Huang1-1/+1
commit c1acb4ac1a892cf08d27efcb964ad281728b0545 upstream. The nesting count of trace_printk allows for 4 levels of nesting. The nesting counter starts at zero and is incremented before being used to retrieve the current context's buffer. But the index to the buffer uses the nesting counter after it was incremented, and not its original number, which in needs to do. Link: https://lkml.kernel.org/r/20201029161905.4269-1-hqjagain@gmail.com Cc: stable@vger.kernel.org Fixes: 3d9622c12c887 ("tracing: Add barrier to trace_printk() buffer nesting modification") Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ftrace: Handle tracing when switching between contextSteven Rostedt (VMware)2-4/+28
commit 726b3d3f141fba6f841d715fc4d8a4a84f02c02a upstream. When an interrupt or NMI comes in and switches the context, there's a delay from when the preempt_count() shows the update. As the preempt_count() is used to detect recursion having each context have its own bit get set when tracing starts, and if that bit is already set, it is considered a recursion and the function exits. But if this happens in that section where context has changed but preempt_count() has not been updated, this will be incorrectly flagged as a recursion. To handle this case, create another bit call TRANSITION and test it if the current context bit is already set. Flag the call as a recursion if the TRANSITION bit is already set, and if not, set it and continue. The TRANSITION bit will be cleared normally on the return of the function that set it, or if the current context bit is clear, set it and clear the TRANSITION bit to allow for another transition between the current context and an even higher one. Cc: stable@vger.kernel.org Fixes: edc15cafcbfa3 ("tracing: Avoid unnecessary multiple recursion checks") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ftrace: Fix recursion check for NMI testSteven Rostedt (VMware)1-1/+2
commit ee11b93f95eabdf8198edd4668bf9102e7248270 upstream. The code that checks recursion will work to only do the recursion check once if there's nested checks. The top one will do the check, the other nested checks will see recursion was already checked and return zero for its "bit". On the return side, nothing will be done if the "bit" is zero. The problem is that zero is returned for the "good" bit when in NMI context. This will set the bit for NMIs making it look like *all* NMI tracing is recursing, and prevent tracing of anything in NMI context! The simple fix is to return "bit + 1" and subtract that bit on the end to get the real bit. Cc: stable@vger.kernel.org Fixes: edc15cafcbfa3 ("tracing: Avoid unnecessary multiple recursion checks") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ring-buffer: Fix recursion protection transitions between interrupt contextSteven Rostedt (VMware)1-12/+46
commit b02414c8f045ab3b9afc816c3735bc98c5c3d262 upstream. The recursion protection of the ring buffer depends on preempt_count() to be correct. But it is possible that the ring buffer gets called after an interrupt comes in but before it updates the preempt_count(). This will trigger a false positive in the recursion code. Use the same trick from the ftrace function callback recursion code which uses a "transition" bit that gets set, to allow for a single recursion for to handle transitions between contexts. Cc: stable@vger.kernel.org Fixes: 567cd4da54ff4 ("ring-buffer: User context bit recursion checking") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05ring-buffer: Return 0 on success from ring_buffer_resize()Qiujun Huang1-4/+4
commit 0a1754b2a97efa644aa6e84d1db5b17c42251483 upstream. We don't need to check the new buffer size, and the return value had confused resize_buffer_duplicate_size(). ... ret = ring_buffer_resize(trace_buf->buffer, per_cpu_ptr(size_buf->data,cpu_id)->entries, cpu_id); if (ret == 0) per_cpu_ptr(trace_buf->data, cpu_id)->entries = per_cpu_ptr(size_buf->data, cpu_id)->entries; ... Link: https://lkml.kernel.org/r/20201019142242.11560-1-hqjagain@gmail.com Cc: stable@vger.kernel.org Fixes: d60da506cbeb3 ("tracing: Add a resize function to make one buffer equivalent to another buffer") Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05tracing: Fix race in trace_open and buffer resize callGaurav Kohli1-0/+10
commit bbeb97464eefc65f506084fd9f18f21653e01137 upstream. Below race can come, if trace_open and resize of cpu buffer is running parallely on different cpus CPUX CPUY ring_buffer_resize atomic_read(&buffer->resize_disabled) tracing_open tracing_reset_online_cpus ring_buffer_reset_cpu rb_reset_cpu rb_update_pages remove/insert pages resetting pointer This race can cause data abort or some times infinte loop in rb_remove_pages and rb_insert_pages while checking pages for sanity. Take buffer lock to fix this. Link: https://lkml.kernel.org/r/1601976833-24377-1-git-send-email-gkohli@codeaurora.org Cc: stable@vger.kernel.org Fixes: b23d7a5f4a07a ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU") Signed-off-by: Gaurav Kohli <gkohli@codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05tracing, synthetic events: Replace buggy strcat() with seq_buf operationsSasha Levin1-11/+12
[ Upstream commit 761a8c58db6bc884994b28cd6d9707b467d680c1 ] There was a memory corruption bug happening while running the synthetic event selftests: kmemleak: Cannot insert 0xffff8c196fa2afe5 into the object search tree (overlaps existing) CPU: 5 PID: 6866 Comm: ftracetest Tainted: G W 5.9.0-rc5-test+ #577 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 Call Trace: dump_stack+0x8d/0xc0 create_object.cold+0x3b/0x60 slab_post_alloc_hook+0x57/0x510 ? tracing_map_init+0x178/0x340 __kmalloc+0x1b1/0x390 tracing_map_init+0x178/0x340 event_hist_trigger_func+0x523/0xa40 trigger_process_regex+0xc5/0x110 event_trigger_write+0x71/0xd0 vfs_write+0xca/0x210 ksys_write+0x70/0xf0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fef0a63a487 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007fff76f18398 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000039 RCX: 00007fef0a63a487 RDX: 0000000000000039 RSI: 000055eb3b26d690 RDI: 0000000000000001 RBP: 000055eb3b26d690 R08: 000000000000000a R09: 0000000000000038 R10: 000055eb3b2cdb80 R11: 0000000000000246 R12: 0000000000000039 R13: 00007fef0a70b500 R14: 0000000000000039 R15: 00007fef0a70b700 kmemleak: Kernel memory leak detector disabled kmemleak: Object 0xffff8c196fa2afe0 (size 8): kmemleak: comm "ftracetest", pid 6866, jiffies 4295082531 kmemleak: min_count = 1 kmemleak: count = 0 kmemleak: flags = 0x1 kmemleak: checksum = 0 kmemleak: backtrace: __kmalloc+0x1b1/0x390 tracing_map_init+0x1be/0x340 event_hist_trigger_func+0x523/0xa40 trigger_process_regex+0xc5/0x110 event_trigger_write+0x71/0xd0 vfs_write+0xca/0x210 ksys_write+0x70/0xf0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The cause came down to a use of strcat() that was adding an string that was shorten, but the strcat() did not take that into account. strcat() is extremely dangerous as it does not care how big the buffer is. Replace it with seq_buf operations that prevent the buffer from being overwritten if what is being written is bigger than the buffer. Fixes: 10819e25799a ("tracing: Handle synthetic event array field type checking correctly") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Tested-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29tracing: Handle synthetic event array field type checking correctlyTom Zanussi1-3/+9
[ Upstream commit 10819e25799aae564005b6049a45e9808797b3bb ] Since synthetic event array types are derived from the field name, there may be a semicolon at the end of the type which should be stripped off. If there are more characters following that, normal type string checking will result in an invalid type. Without this patch, you can end up with an invalid field type string that gets displayed in both the synthetic event description and the event format: Before: # echo 'myevent char str[16]; int v' >> synthetic_events # cat synthetic_events myevent char[16]; str; int v name: myevent ID: 1936 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:char str[16];; offset:8; size:16; signed:1; field:int v; offset:40; size:4; signed:1; print fmt: "str=%s, v=%d", REC->str, REC->v After: # echo 'myevent char str[16]; int v' >> synthetic_events # cat synthetic_events myevent char[16] str; int v # cat events/synthetic/myevent/format name: myevent ID: 1936 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:char str[16]; offset:8; size:16; signed:1; field:int v; offset:40; size:4; signed:1; print fmt: "str=%s, v=%d", REC->str, REC->v Link: https://lkml.kernel.org/r/6587663b56c2d45ab9d8c8472a2110713cdec97d.1602598160.git.zanussi@kernel.org [ <rostedt@goodmis.org>: wrote parse_synth_field() snippet. ] Fixes: 4b147936fa50 (tracing: Add support for 'synthetic' events) Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29tracing: Fix parse_synth_field() error handlingTom Zanussi1-2/+4
[ Upstream commit 8fbeb52a598c7ab5aa603d6bb083b8a8d16d607a ] synth_field_size() returns either a positive size or an error (zero or a negative value). However, the existing code assumes the only error value is 0. It doesn't handle negative error codes, as it assigns directly to field->size (a size_t; unsigned), thereby interpreting the error code as a valid size instead. Do the test before assignment to field->size. [ axelrasmussen@google.com: changelog addition, first paragraph above ] Link: https://lkml.kernel.org/r/9b6946d9776b2eeb43227678158196de1c3c6e1d.1601848695.git.zanussi@kernel.org Fixes: 4b147936fa50 (tracing: Add support for 'synthetic' events) Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Axel Rasmussen <axelrasmussen@google.com> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01Merge tag 'trace-v5.9-rc6' of ↵Linus Torvalds2-8/+8
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Two tracing fixes: - Fix temp buffer accounting that caused a WARNING for ftrace_dump_on_opps() - Move the recursion check in one of the function callback helpers to the beginning of the function, as if the rcu_is_watching() gets traced, it will cause a recursive loop that will crash the kernel" * tag 'trace-v5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Move RCU is watching check after recursion check tracing: Fix trace_find_next_entry() accounting of temp buffer size
2020-09-29ftrace: Move RCU is watching check after recursion checkSteven Rostedt (VMware)1-4/+2
The first thing that the ftrace function callback helper functions should do is to check for recursion. Peter Zijlstra found that when "rcu_is_watching()" had its notrace removed, it caused perf function tracing to crash. This is because the call of rcu_is_watching() is tested before function recursion is checked and and if it is traced, it will cause an infinite recursion loop. rcu_is_watching() should still stay notrace, but to prevent this should never had crashed in the first place. The recursion prevention must be the first thing done in callback functions. Link: https://lore.kernel.org/r/20200929112541.GM2628@hirez.programming.kicks-ass.net Cc: stable@vger.kernel.org Cc: Paul McKenney <paulmck@kernel.org> Fixes: c68c0fa293417 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too") Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-29tracing: Fix trace_find_next_entry() accounting of temp buffer sizeSteven Rostedt (VMware)1-4/+6
The temp buffer size variable for trace_find_next_entry() was incorrectly being updated when the size did not change. The temp buffer size should only be updated when it is reallocated. This is mostly an issue when used with ftrace_dump(). That's because ftrace_dump() can not allocate a new buffer, and instead uses a temporary buffer with a fix size. But the variable that keeps track of that size is incorrectly updated with each call, and it could fall into the path that would try to reallocate the buffer and produce a warning. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1601 at kernel/trace/trace.c:3548 trace_find_next_entry+0xd0/0xe0 Modules linked in [..] CPU: 1 PID: 1601 Comm: bash Not tainted 5.9.0-rc5-test+ #521 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:trace_find_next_entry+0xd0/0xe0 Code: 40 21 00 00 4c 89 e1 31 d2 4c 89 ee 48 89 df e8 c6 9e ff ff 89 ab 54 21 00 00 5b 5d 41 5c 41 5d c3 48 63 d5 eb bf 31 c0 eb f0 <0f> 0b 48 63 d5 eb b4 66 0f 1f 84 00 00 00 00 00 53 48 8d 8f 60 21 RSP: 0018:ffff95a4f2e8bd70 EFLAGS: 00010046 RAX: ffffffff96679fc0 RBX: ffffffff97910de0 RCX: ffffffff96679fc0 RDX: ffff95a4f2e8bd98 RSI: ffff95a4ee321098 RDI: ffffffff97913000 RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000046 R12: ffff95a4f2e8bd98 R13: 0000000000000000 R14: ffff95a4ee321098 R15: 00000000009aa301 FS: 00007f8565484740(0000) GS:ffff95a55aa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055876bd43d90 CR3: 00000000b76e6003 CR4: 00000000001706e0 Call Trace: trace_print_lat_context+0x58/0x2d0 ? cpumask_next+0x16/0x20 print_trace_line+0x1a4/0x4f0 ftrace_dump.cold+0xad/0x12c __handle_sysrq.cold+0x51/0x126 write_sysrq_trigger+0x3f/0x4a proc_reg_write+0x53/0x80 vfs_write+0xca/0x210 ksys_write+0x70/0xf0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8565579487 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007ffd40707948 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8565579487 RDX: 0000000000000002 RSI: 000055876bd74de0 RDI: 0000000000000001 RBP: 000055876bd74de0 R08: 000000000000000a R09: 0000000000000001 R10: 000055876bdec280 R11: 0000000000000246 R12: 0000000000000002 R13: 00007f856564a500 R14: 0000000000000002 R15: 00007f856564a700 irq event stamp: 109958 ---[ end trace 7aab5b7e51484b00 ]--- Not only fix the updating of the temp buffer, but also do not free the temp buffer before a new buffer is allocated (there's no reason to not continue to use the current temp buffer if an allocation fails). Cc: stable@vger.kernel.org Fixes: 8e99cf91b99bb ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic") Reported-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-22Merge tag 'trace-v5.9-rc5' of ↵Linus Torvalds4-26/+28
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Check kprobe is enabled before unregistering from ftrace as it isn't registered when disabled. - Remove kprobes enabled via command-line that is on init text when freed. - Add missing RCU synchronization for ftrace trampoline symbols removed from kallsyms. - Free trampoline on error path if ftrace_startup() fails. - Give more space for the longer PID numbers in trace output. - Fix a possible double free in the histogram code. - A couple of fixes that were discovered by sparse. * tag 'trace-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: bootconfig: init: make xbc_namebuf static kprobes: tracing/kprobes: Fix to kill kprobes on initmem after boot tracing: fix double free ftrace: Let ftrace_enable_sysctl take a kernel pointer buffer tracing: Make the space reserved for the pid wider ftrace: Fix missing synchronize_rcu() removing trampoline from kallsyms ftrace: Free the trampoline when ftrace_startup() fails kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-09-19Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-2/+1
Merge fixes from Andrew Morton: "15 patches. Subsystems affected by this patch series: mailmap, mm/hotfixes, mm/thp, mm/memory-hotplug, misc, kcsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments' fs/fs-writeback.c: adjust dirtytime_interval_handler definition to match prototype stackleak: let stack_erasing_sysctl take a kernel pointer buffer ftrace: let ftrace_enable_sysctl take a kernel pointer buffer mm/memory_hotplug: drain per-cpu pages again during memory offline selftests/vm: fix display of page size in map_hugetlb mm/thp: fix __split_huge_pmd_locked() for migration PMD kprobes: fix kill kprobe which has been marked as gone tmpfs: restore functionality of nr_inodes=0 mlock: fix unevictable_pgs event counts on THP mm: fix check_move_unevictable_pages() on THP mm: migration of hugetlbfs page skip memcg ksm: reinstate memcg charge on copied pages mailmap: add older email addresses for Kees Cook
2020-09-19ftrace: let ftrace_enable_sysctl take a kernel pointer bufferTobias Klauser1-2/+1
Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") changed ctl_table.proc_handler to take a kernel pointer. Adjust the signature of ftrace_enable_sysctl to match ctl_table.proc_handler which fixes the following sparse warning: kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces) kernel/trace/ftrace.c:7544:43: expected void * kernel/trace/ftrace.c:7544:43: got void [noderef] __user *buffer Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Link: https://lkml.kernel.org/r/20200907093207.13540-1-tklauser@distanz.ch Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-18tracing: fix double freeTom Rix1-1/+0
clang static analyzer reports this problem trace_events_hist.c:3824:3: warning: Attempt to free released memory kfree(hist_data->attrs->var_defs.name[i]); In parse_var_defs() if there is a problem allocating var_defs.expr, the earlier var_defs.name is freed. This free is duplicated by free_var_defs() which frees the rest of the list. Because free_var_defs() has to run anyway, remove the second free fom parse_var_defs(). Link: https://lkml.kernel.org/r/20200907135845.15804-1-trix@redhat.com Cc: stable@vger.kernel.org Fixes: 30350d65ac56 ("tracing: Add variable support to hist triggers") Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Tom Rix <trix@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18ftrace: Let ftrace_enable_sysctl take a kernel pointer bufferTobias Klauser1-2/+1
Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") changed ctl_table.proc_handler to take a kernel pointer. Adjust the signature of ftrace_enable_sysctl to match ctl_table.proc_handler which fixes the following sparse warning: kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces) kernel/trace/ftrace.c:7544:43: expected void * kernel/trace/ftrace.c:7544:43: got void [noderef] __user *buffer Link: https://lkml.kernel.org/r/20200907093207.13540-1-tklauser@distanz.ch Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18tracing: Make the space reserved for the pid widerSebastian Andrzej Siewior2-25/+25
For 64bit CONFIG_BASE_SMALL=0 systems PID_MAX_LIMIT is set by default to 4194304. During boot the kernel sets a new value based on number of CPUs but no lower than 32768. It is 1024 per CPU so with 128 CPUs the default becomes 131072 which needs six digits. This value can be increased during run time but must not exceed the initial upper limit. Systemd sometime after v241 sets it to the upper limit during boot. The result is that when the pid exceeds five digits, the trace output is a little hard to read because it is no longer properly padded (same like on big iron with 98+ CPUs). Increase the pid padding to seven digits. Link: https://lkml.kernel.org/r/20200904082331.dcdkrr3bkn3e4qlg@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18ftrace: Fix missing synchronize_rcu() removing trampoline from kallsymsAdrian Hunter1-0/+1
Add synchronize_rcu() after list_del_rcu() in ftrace_remove_trampoline_from_kallsyms() to protect readers of ftrace_ops_trampoline_list (in ftrace_get_trampoline_kallsym) which is used when kallsyms is read. Link: https://lkml.kernel.org/r/20200901091617.31837-1-adrian.hunter@intel.com Fixes: fc0ea795f53c8d ("ftrace: Add symbols for ftrace trampolines") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18ftrace: Free the trampoline when ftrace_startup() failsMiroslav Benes1-0/+2
Commit fc0ea795f53c ("ftrace: Add symbols for ftrace trampolines") missed to remove ops from new ftrace_ops_trampoline_list in ftrace_startup() if ftrace_hash_ipmodify_enable() fails there. It may lead to BUG if such ops come from a module which may be removed. Moreover, the trampoline itself is not freed in this case. Fix it by calling ftrace_trampoline_free() during the rollback. Link: https://lkml.kernel.org/r/20200831122631.28057-1-mbenes@suse.cz Fixes: fc0ea795f53c ("ftrace: Add symbols for ftrace trampolines") Fixes: f8b8be8a310a ("ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict") Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-14lockdep: fix order in trace_hardirqs_off_caller()Sven Schnelle1-2/+2
Switch order so that locking state is consistent even if the IRQ tracer calls into lockdep again. Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2-3/+3
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds1-1/+1
Pull networking fixes from David Miller: "Some merge window fallout, some longer term fixes: 1) Handle headroom properly in lapbether and x25_asy drivers, from Xie He. 2) Fetch MAC address from correct r8152 device node, from Thierry Reding. 3) In the sw kTLS path we should allow MSG_CMSG_COMPAT in sendmsg, from Rouven Czerwinski. 4) Correct fdputs in socket layer, from Miaohe Lin. 5) Revert troublesome sockptr_t optimization, from Christoph Hellwig. 6) Fix TCP TFO key reading on big endian, from Jason Baron. 7) Missing CAP_NET_RAW check in nfc, from Qingyu Li. 8) Fix inet fastreuse optimization with tproxy sockets, from Tim Froidcoeur. 9) Fix 64-bit divide in new SFC driver, from Edward Cree. 10) Add a tracepoint for prandom_u32 so that we can more easily perform usage analysis. From Eric Dumazet. 11) Fix rwlock imbalance in AF_PACKET, from John Ogness" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (49 commits) net: openvswitch: introduce common code for flushing flows af_packet: TPACKET_V3: fix fill status rwlock imbalance random32: add a tracepoint for prandom_u32() Revert "ipv4: tunnel: fix compilation on ARCH=um" net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpus net: ethernet: stmmac: Disable hardware multicast filter net: stmmac: dwmac1000: provide multicast filter fallback ipv4: tunnel: fix compilation on ARCH=um vsock: fix potential null pointer dereference in vsock_poll() sfc: fix ef100 design-param checking net: initialize fastreuse on inet_inherit_port net: refactor bind_bucket fastreuse into helper net: phy: marvell10g: fix null pointer dereference net: Fix potential memory leak in proto_register() net: qcom/emac: add missed clk_disable_unprepare in error path of emac_clks_phase1_init ionic_lif: Use devm_kcalloc() in ionic_qcq_alloc() net/nfc/rawsock.c: add CAP_NET_RAW check. hinic: fix strncpy output truncated compile warnings drivers/net/wan/x25_asy: Added needed_headroom and a skb->len check net/tls: Fix kmap usage ...
2020-08-09Merge tag 'kbuild-v5.9' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - run the checker (e.g. sparse) after the compiler - remove unneeded cc-option tests for old compiler flags - fix tar-pkg to install dtbs - introduce ccflags-remove-y and asflags-remove-y syntax - allow to trace functions in sub-directories of lib/ - introduce hostprogs-always-y and userprogs-always-y syntax - various Makefile cleanups * tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled kbuild: introduce hostprogs-always-y and userprogs-always-y kbuild: sort hostprogs before passing it to ifneq kbuild: move host .so build rules to scripts/gcc-plugins/Makefile kbuild: Replace HTTP links with HTTPS ones kbuild: trace functions in subdirectories of lib/ kbuild: introduce ccflags-remove-y and asflags-remove-y kbuild: do not export LDFLAGS_vmlinux kbuild: always create directories of targets powerpc/boot: add DTB to 'targets' kbuild: buildtar: add dtbs support kbuild: remove cc-option test of -ffreestanding kbuild: remove cc-option test of -fno-stack-protector Revert "kbuild: Create directory for target DTB" kbuild: run the checker after the compiler
2020-08-10kbuild: introduce ccflags-remove-y and asflags-remove-yMasahiro Yamada1-2/+2
CFLAGS_REMOVE_<file>.o filters out flags when compiling a particular object, but there is no convenient way to do that for every object in a directory. Add ccflags-remove-y and asflags-remove-y to make it easily. Use ccflags-remove-y to clean up some Makefiles. The add/remove order works as follows: [1] KBUILD_CFLAGS specifies compiler flags used globally [2] ccflags-y adds compiler flags for all objects in the current Makefile [3] ccflags-remove-y removes compiler flags for all objects in the current Makefile (New feature) [4] CFLAGS_<file> adds compiler flags per file. [5] CFLAGS_REMOVE_<file> removes compiler flags per file. Having [3] before [4] allows us to remove flags from most (but not all) objects in the current Makefile. For example, kernel/trace/Makefile removes $(CC_FLAGS_FTRACE) from all objects in the directory, then adds it back to trace_selftest_dynamic.o and CFLAGS_trace_kprobe_selftest.o The same applies to lib/livepatch/Makefile. Please note ccflags-remove-y has no effect to the sub-directories. In contrast, the previous notation got rid of compiler flags also from all the sub-directories. The following are not affected because they have no sub-directories: arch/arm/boot/compressed/ arch/powerpc/xmon/ arch/sh/ kernel/trace/ However, lib/ has several sub-directories. To keep the behavior, I added ccflags-remove-y to all Makefiles in subdirectories of lib/, except the following: lib/vdso/Makefile - Kbuild does not descend into this Makefile lib/raid/test/Makefile - This is not used for the kernel build I think commit 2464a609ded0 ("ftrace: do not trace library functions") excluded too much. In the next commit, I will remove ccflags-remove-y from the sub-directories of lib/. Suggested-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Acked-by: Brendan Higgins <brendanhiggins@google.com> (KUnit) Tested-by: Anders Roxell <anders.roxell@linaro.org>
2020-08-07Merge tag 'trace-v5.9' of ↵Linus Torvalds8-189/+653
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - The biggest news in that the tracing ring buffer can now time events that interrupted other ring buffer events. Before this change, if an interrupt came in while recording another event, and that interrupt also had an event, those events would all have the same time stamp as the event it interrupted. Now, with the new design, those events will have a unique time stamp and rightfully display the time for those events that were recorded while interrupting another event. - Bootconfig how has an "override" operator that lets the users have a default config, but then add options to override the default. - A fix was made to properly filter function graph tracing to the ftrace PIDs. This came in at the end of the -rc cycle, and needs to be backported. - Several clean ups, performance updates, and minor fixes as well. * tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (39 commits) tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACE tracing: Use trace_sched_process_free() instead of exit() for pid tracing bootconfig: Fix to find the initargs correctly Documentation: bootconfig: Add bootconfig override operator tools/bootconfig: Add testcases for value override operator lib/bootconfig: Add override operator support kprobes: Remove show_registers() function prototype tracing/uprobe: Remove dead code in trace_uprobe_register() kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler ftrace: Fix ftrace_trace_task return value tracepoint: Use __used attribute definitions from compiler_attributes.h tracepoint: Mark __tracepoint_string's __used trace : Have tracing buffer info use kvzalloc instead of kzalloc tracing: Remove outdated comment in stack handling ftrace: Do not let direct or IPMODIFY ftrace_ops be added to module and set trampolines ftrace: Setup correct FTRACE_FL_REGS flags for module tracing/hwlat: Honor the tracing_cpumask tracing/hwlat: Drop the duplicate assignment in start_kthread() tracing: Save one trace_event->type by using __TRACE_LAST_TYPE ...
2020-08-07tracing: Add trace_array_init_printk() to initialize instance trace_printk() ↵Steven Rostedt (VMware)1-0/+44
buffers As trace_array_printk() used with not global instances will not add noise to the main buffer, they are OK to have in the kernel (unlike trace_printk()). This require the subsystem to create their own tracing instance, and the trace_array_printk() only writes into those instances. Add trace_array_init_printk() to initialize the trace_printk() buffers without printing out the WARNING message. Reported-by: Sean Paul <sean@poorly.run> Reviewed-by: Sean Paul <sean@poorly.run> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-08-06Merge tag 'fsnotify_for_v5.9-rc1' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: - fanotify fix for softlockups when there are many queued events - performance improvement to reduce fsnotify overhead when not used - Amir's implementation of fanotify events with names. With these you can now efficiently monitor whole filesystem, eg to mirror changes to another machine. * tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits) fanotify: compare fsid when merging name event fsnotify: create method handle_inode_event() in fsnotify_operations fanotify: report parent fid + child fid fanotify: report parent fid + name + child fid fanotify: add support for FAN_REPORT_NAME fanotify: report events with parent dir fid to sb/mount/non-dir marks fanotify: add basic support for FAN_REPORT_DIR_FID fsnotify: remove check that source dentry is positive fsnotify: send event with parent/name info to sb/mount/non-dir marks audit: do not set FS_EVENT_ON_CHILD in audit marks mask inotify: do not set FS_EVENT_ON_CHILD in non-dir mark mask fsnotify: pass dir and inode arguments to fsnotify() fsnotify: create helper fsnotify_inode() fsnotify: send event to parent and child with single callback inotify: report both events on parent and child with single callback dnotify: report both events on parent and child with single callback fanotify: no external fh buffer in fanotify_name_event fanotify: use struct fanotify_info to parcel the variable size buffer fsnotify: add object type "child" to object type iterator fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks ...
2020-08-06bpf: Remove inline from bpf_do_trace_printkStanislav Fomichev1-1/+1
I get the following error during compilation on my side: kernel/trace/bpf_trace.c: In function 'bpf_do_trace_printk': kernel/trace/bpf_trace.c:386:34: error: function 'bpf_do_trace_printk' can never be inlined because it uses variable argument lists static inline __printf(1, 0) int bpf_do_trace_printk(const char *fmt, ...) ^ Fixes: ac5a72ea5c89 ("bpf: Use dedicated bpf_trace_printk event instead of trace_printk()") Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200806182612.1390883-1-sdf@google.com
2020-08-06Merge tag 'sched-fifo-2020-08-04' of ↵Linus Torvalds1-25/+23
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull sched/fifo updates from Ingo Molnar: "This adds the sched_set_fifo*() encapsulation APIs to remove static priority level knowledge from non-scheduler code. The three APIs for non-scheduler code to set SCHED_FIFO are: - sched_set_fifo() - sched_set_fifo_low() - sched_set_normal() These are two FIFO priority levels: default (high), and a 'low' priority level, plus sched_set_normal() to set the policy back to non-SCHED_FIFO. Since the changes affect a lot of non-scheduler code, we kept this in a separate tree" * tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) sched,tracing: Convert to sched_set_fifo() sched: Remove sched_set_*() return value sched: Remove sched_setscheduler*() EXPORTs sched,psi: Convert to sched_set_fifo_low() sched,rcutorture: Convert to sched_set_fifo_low() sched,rcuperf: Convert to sched_set_fifo_low() sched,locktorture: Convert to sched_set_fifo() sched,irq: Convert to sched_set_fifo() sched,watchdog: Convert to sched_set_fifo() sched,serial: Convert to sched_set_fifo() sched,powerclamp: Convert to sched_set_fifo() sched,ion: Convert to sched_set_normal() sched,powercap: Convert to sched_set_fifo*() sched,spi: Convert to sched_set_fifo*() sched,mmc: Convert to sched_set_fifo*() sched,ivtv: Convert to sched_set_fifo*() sched,drm/scheduler: Convert to sched_set_fifo*() sched,msm: Convert to sched_set_fifo*() sched,psci: Convert to sched_set_fifo*() sched,drbd: Convert to sched_set_fifo*() ...
2020-08-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds3-12/+106
Pull networking updates from David Miller: 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan. 2) Support UDP segmentation in code TSO code, from Eric Dumazet. 3) Allow flashing different flash images in cxgb4 driver, from Vishal Kulkarni. 4) Add drop frames counter and flow status to tc flower offloading, from Po Liu. 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni. 6) Various new indirect call avoidance, from Eric Dumazet and Brian Vazquez. 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from Yonghong Song. 8) Support querying and setting hardware address of a port function via devlink, use this in mlx5, from Parav Pandit. 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson. 10) Switch qca8k driver over to phylink, from Jonathan McDowell. 11) In bpftool, show list of processes holding BPF FD references to maps, programs, links, and btf objects. From Andrii Nakryiko. 12) Several conversions over to generic power management, from Vaibhav Gupta. 13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry Yakunin. 14) Various https url conversions, from Alexander A. Klimov. 15) Timestamping and PHC support for mscc PHY driver, from Antoine Tenart. 16) Support bpf iterating over tcp and udp sockets, from Yonghong Song. 17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov. 18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan. 19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several drivers. From Luc Van Oostenryck. 20) XDP support for xen-netfront, from Denis Kirjanov. 21) Support receive buffer autotuning in MPTCP, from Florian Westphal. 22) Support EF100 chip in sfc driver, from Edward Cree. 23) Add XDP support to mvpp2 driver, from Matteo Croce. 24) Support MPTCP in sock_diag, from Paolo Abeni. 25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic infrastructure, from Jakub Kicinski. 26) Several pci_ --> dma_ API conversions, from Christophe JAILLET. 27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel. 28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki. 29) Refactor a lot of networking socket option handling code in order to avoid set_fs() calls, from Christoph Hellwig. 30) Add rfc4884 support to icmp code, from Willem de Bruijn. 31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei. 32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin. 33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin. 34) Support TCP syncookies in MPTCP, from Flowian Westphal. 35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano Brivio. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits) net: thunderx: initialize VF's mailbox mutex before first usage usb: hso: remove bogus check for EINPROGRESS usb: hso: no complaint about kmalloc failure hso: fix bailout in error case of probe ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM selftests/net: relax cpu affinity requirement in msg_zerocopy test mptcp: be careful on subflow creation selftests: rtnetlink: make kci_test_encap() return sub-test result selftests: rtnetlink: correct the final return value for the test net: dsa: sja1105: use detected device id instead of DT one on mismatch tipc: set ub->ifindex for local ipv6 address ipv6: add ipv6_dev_find() net: openvswitch: silence suspicious RCU usage warning Revert "vxlan: fix tos value before xmit" ptp: only allow phase values lower than 1 period farsync: switch from 'pci_' to 'dma_' API wan: wanxl: switch from 'pci_' to 'dma_' API hv_netvsc: do not use VF device if link is down dpaa2-eth: Fix passing zero to 'PTR_ERR' warning net: macb: Properly handle phylink on at91sam9x ...
2020-08-05Merge tag 'driver-core-5.9-rc1' of ↵Linus Torvalds1-3/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of changes to the driver core, and some drivers using the changes, for 5.9-rc1. "Biggest" thing in here is the device link exposure in sysfs, to help to tame the madness that is SoC device tree representations and driver interactions with it. Other stuff in here that is interesting is: - device probe log helper so that drivers can report problems in a unified way easier. - devres functions added - DEVICE_ATTR_ADMIN_* macro added to make it harder to write incorrect sysfs file permissions - documentation cleanups - ability for debugfs to be present in the kernel, yet not exposed to userspace. Needed for systems that want it enabled, but do not trust users, so they can still use some kernel functions that were otherwise disabled. - other minor fixes and cleanups The patches outside of drivers/base/ all have acks from the respective subsystem maintainers to go through this tree instead of theirs. All of these have been in linux-next with no reported issues" * tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits) drm/bridge: lvds-codec: simplify error handling drm/bridge/sii8620: fix resource acquisition error handling driver core: add deferring probe reason to devices_deferred property driver core: add device probe log helper driver core: Avoid binding drivers to dead devices Revert "test_firmware: Test platform fw loading on non-EFI systems" firmware_loader: EFI firmware loader must handle pre-allocated buffer selftest/firmware: Add selftest timeout in settings test_firmware: Test platform fw loading on non-EFI systems driver core: Change delimiter in devlink device's name to "--" debugfs: Add access restriction option tracefs: Remove unnecessary debug_fs checks. driver core: Fix probe_count imbalance in really_probe() kobject: remove unused KOBJ_MAX action driver core: Fix sleeping in invalid context during device link deletion driver core: Add waiting_for_supplier sysfs file for devices driver core: Add state_synced sysfs file for devices that support it driver core: Expose device link details in sysfs driver core: Drop mention of obsolete bus rwsem from kernel-doc debugfs: file: Remove unnecessary cast in kfree() ...
2020-08-04tracing: Use trace_sched_process_free() instead of exit() for pid tracingSteven Rostedt (VMware)2-4/+4
On exit, if a process is preempted after the trace_sched_process_exit() tracepoint but before the process is done exiting, then when it gets scheduled in, the function tracers will not filter it properly against the function trac