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2022-12-31tracing/hist: Fix issue of losting command info in error_logZheng Yejian1-1/+1
[ Upstream commit 608c6ed3337850c767ab0dd6c583477922233e29 ] When input some constructed invalid 'trigger' command, command info in 'error_log' are lost [1]. The root cause is that there is a path that event_hist_trigger_parse() is recursely called once and 'last_cmd' which save origin command is cleared, then later calling of hist_err() will no longer record origin command info: event_hist_trigger_parse() { last_cmd_set() // <1> 'last_cmd' save origin command here at first create_actions() { onmatch_create() { action_create() { trace_action_create() { trace_action_create_field_var() { create_field_var_hist() { event_hist_trigger_parse() { // <2> recursely called once hist_err_clear() // <3> 'last_cmd' is cleared here } hist_err() // <4> No longer find origin command!!! Since 'glob' is empty string while running into the recurse call, we can trickly check it and bypass the call of hist_err_clear() to solve it. [1] # cd /sys/kernel/tracing # echo "my_synth_event int v1; int v2; int v3;" >> synthetic_events # echo 'hist:keys=pid' >> events/sched/sched_waking/trigger # echo "hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(\ pid,pid1)" >> events/sched/sched_switch/trigger # cat error_log [ 8.405018] hist:sched:sched_switch: error: Couldn't find synthetic event Command: hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1) ^ [ 8.816902] hist:sched:sched_switch: error: Couldn't find field Command: hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1) ^ [ 8.816902] hist:sched:sched_switch: error: Couldn't parse field variable Command: hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1) ^ [ 8.999880] : error: Couldn't find field Command: ^ [ 8.999880] : error: Couldn't parse field variable Command: ^ [ 8.999880] : error: Couldn't find field Command: ^ [ 8.999880] : error: Couldn't create histogram for field Command: ^ Link: https://lore.kernel.org/linux-trace-kernel/20221207135326.3483216-1-zhengyejian1@huawei.com Cc: <mhiramat@kernel.org> Cc: <zanussi@kernel.org> Fixes: f404da6e1d46 ("tracing: Add 'last error' error facility for hist triggers") Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31tracing/user_events: Fix call print_fmt leakBeau Belgrave1-0/+1
[ Upstream commit 4bded7af8b9af6e97514b0521004f90267905aef ] If user_event_trace_register() fails within user_event_parse() the call's print_fmt member is not freed. Add kfree call to fix this. Link: https://lkml.kernel.org/r/20221123183248.554-1-beaub@linux.microsoft.com Fixes: aa3b2b4c6692 ("user_events: Add print_fmt generation support for basic types") Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31blktrace: Fix output non-blktrace event when blk_classic option enabledYang Jihong1-1/+2
[ Upstream commit f596da3efaf4130ff61cd029558845808df9bf99 ] When the blk_classic option is enabled, non-blktrace events must be filtered out. Otherwise, events of other types are output in the blktrace classic format, which is unexpected. The problem can be triggered in the following ways: # echo 1 > /sys/kernel/debug/tracing/options/blk_classic # echo 1 > /sys/kernel/debug/tracing/events/enable # echo blk > /sys/kernel/debug/tracing/current_tracer # cat /sys/kernel/debug/tracing/trace_pipe Fixes: c71a89615411 ("blktrace: add ftrace plugin") Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20221122040410.85113-1-yangjihong1@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-23tracing: Free buffers when a used dynamic event is removedSteven Rostedt (Google)2-1/+12
After 65536 dynamic events have been added and removed, the "type" field of the event then uses the first type number that is available (not currently used by other events). A type number is the identifier of the binary blobs in the tracing ring buffer (known as events) to map them to logic that can parse the binary blob. The issue is that if a dynamic event (like a kprobe event) is traced and is in the ring buffer, and then that event is removed (because it is dynamic, which means it can be created and destroyed), if another dynamic event is created that has the same number that new event's logic on parsing the binary blob will be used. To show how this can be an issue, the following can crash the kernel: # cd /sys/kernel/tracing # for i in `seq 65536`; do echo 'p:kprobes/foo do_sys_openat2 $arg1:u32' > kprobe_events # done For every iteration of the above, the writing to the kprobe_events will remove the old event and create a new one (with the same format) and increase the type number to the next available on until the type number reaches over 65535 which is the max number for the 16 bit type. After it reaches that number, the logic to allocate a new number simply looks for the next available number. When an dynamic event is removed, that number is then available to be reused by the next dynamic event created. That is, once the above reaches the max number, the number assigned to the event in that loop will remain the same. Now that means deleting one dynamic event and created another will reuse the previous events type number. This is where bad things can happen. After the above loop finishes, the kprobes/foo event which reads the do_sys_openat2 function call's first parameter as an integer. # echo 1 > kprobes/foo/enable # cat /etc/passwd > /dev/null # cat trace cat-2211 [005] .... 2007.849603: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196 cat-2211 [005] .... 2007.849620: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196 cat-2211 [005] .... 2007.849838: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196 cat-2211 [005] .... 2007.849880: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196 # echo 0 > kprobes/foo/enable Now if we delete the kprobe and create a new one that reads a string: # echo 'p:kprobes/foo do_sys_openat2 +0($arg2):string' > kprobe_events And now we can the trace: # cat trace sendmail-1942 [002] ..... 530.136320: foo: (do_sys_openat2+0x0/0x240) arg1= cat-2046 [004] ..... 530.930817: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������" cat-2046 [004] ..... 530.930961: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������" cat-2046 [004] ..... 530.934278: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������" cat-2046 [004] ..... 530.934563: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������" bash-1515 [007] ..... 534.299093: foo: (do_sys_openat2+0x0/0x240) arg1="kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk���������@��4Z����;Y�����U And dmesg has: ================================================================== BUG: KASAN: use-after-free in string+0xd4/0x1c0 Read of size 1 at addr ffff88805fdbbfa0 by task cat/2049 CPU: 0 PID: 2049 Comm: cat Not tainted 6.1.0-rc6-test+ #641 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 Call Trace: <TASK> dump_stack_lvl+0x5b/0x77 print_report+0x17f/0x47b kasan_report+0xad/0x130 string+0xd4/0x1c0 vsnprintf+0x500/0x840 seq_buf_vprintf+0x62/0xc0 trace_seq_printf+0x10e/0x1e0 print_type_string+0x90/0xa0 print_kprobe_event+0x16b/0x290 print_trace_line+0x451/0x8e0 s_show+0x72/0x1f0 seq_read_iter+0x58e/0x750 seq_read+0x115/0x160 vfs_read+0x11d/0x460 ksys_read+0xa9/0x130 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fc2e972ade2 Code: c0 e9 b2 fe ff ff 50 48 8d 3d b2 3f 0a 00 e8 05 f0 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 RSP: 002b:00007ffc64e687c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2e972ade2 RDX: 0000000000020000 RSI: 00007fc2e980d000 RDI: 0000000000000003 RBP: 00007fc2e980d000 R08: 00007fc2e980c010 R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000020f00 R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000 </TASK> The buggy address belongs to the physical page: page:ffffea00017f6ec0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fdbb flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0000000 0000000000000000 ffffea00017f6ec8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805fdbbe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805fdbbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88805fdbbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805fdbc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805fdbc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== This was found when Zheng Yejian sent a patch to convert the event type number assignment to use IDA, which gives the next available number, and this bug showed up in the fuzz testing by Yujie Liu and the kernel test robot. But after further analysis, I found that this behavior is the same as when the event type numbers go past the 16bit max (and the above shows that). As modules have a similar issue, but is dealt with by setting a "WAS_ENABLED" flag when a module event is enabled, and when the module is freed, if any of its events were enabled, the ring buffer that holds that event is also cleared, to prevent reading stale events. The same can be done for dynamic events. If any dynamic event that is being removed was enabled, then make sure the buffers they were enabled in are now cleared. Link: https://lkml.kernel.org/r/20221123171434.545706e3@gandalf.local.home Link: https://lore.kernel.org/all/20221110020319.1259291-1-zhengyejian1@huawei.com/ Cc: stable@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Depends-on: e18eb8783ec49 ("tracing: Add tracing_reset_all_online_cpus_unlocked() function") Depends-on: 5448d44c38557 ("tracing: Add unified dynamic event framework") Depends-on: 6212dd29683ee ("tracing/kprobes: Use dyn_event framework for kprobe events") Depends-on: 065e63f951432 ("tracing: Only have rmmod clear buffers that its events were active in") Depends-on: 575380da8b469 ("tracing: Only clear trace buffer on module unload if event was traced") Fixes: 77b44d1b7c283 ("tracing/kprobes: Rename Kprobe-tracer to kprobe-event") Reported-by: Zheng Yejian <zhengyejian1@huawei.com> Reported-by: Yujie Liu <yujie.liu@intel.com> Reported-by: kernel test robot <yujie.liu@intel.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-23tracing: Add tracing_reset_all_online_cpus_unlocked() functionSteven Rostedt (Google)4-4/+12
Currently the tracing_reset_all_online_cpus() requires the trace_types_lock held. But only one caller of this function actually has that lock held before calling it, and the other just takes the lock so that it can call it. More users of this function is needed where the lock is not held. Add a tracing_reset_all_online_cpus_unlocked() function for the one use case that calls it without being held, and also add a lockdep_assert to make sure it is held when called. Then have tracing_reset_all_online_cpus() take the lock internally, such that callers do not need to worry about taking it. Link: https://lkml.kernel.org/r/20221123192741.658273220@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-23tracing: Fix race where histograms can be called before the eventSteven Rostedt (Google)1-0/+3
commit 94eedf3dded5 ("tracing: Fix race where eprobes can be called before the event") fixed an issue where if an event is soft disabled, and the trigger is being added, there's a small window where the event sees that there's a trigger but does not see that it requires reading the event yet, and then calls the trigger with the record == NULL. This could be solved with adding memory barriers in the hot path, or to make sure that all the triggers requiring a record check for NULL. The latter was chosen. Commit 94eedf3dded5 set the eprobe trigger handle to check for NULL, but the same needs to be done with histograms. Link: https://lore.kernel.org/linux-trace-kernel/20221118211809.701d40c0f8a757b0df3c025a@kernel.org/ Link: https://lore.kernel.org/linux-trace-kernel/20221123164323.03450c3a@gandalf.local.home Cc: Tom Zanussi <zanussi@kernel.org> Cc: stable@vger.kernel.org Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events") Reported-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-22tracing/osnoise: Fix duration typeDaniel Bristot de Oliveira1-3/+3
The duration type is a 64 long value, not an int. This was causing some long noise to report wrong values. Change the duration to a 64 bits value. Link: https://lkml.kernel.org/r/a93d8a8378c7973e9c609de05826533c9e977939.1668692096.git.bristot@kernel.org Cc: stable@vger.kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-22tracing/user_events: Fix memory leak in user_event_create()Xiu Jianfeng1-1/+3
Before current_user_event_group(), it has allocated memory and save it in @name, this should freed before return error. Link: https://lkml.kernel.org/r/20221115014445.158419-1-xiujianfeng@huawei.com Fixes: e5d271812e7a ("tracing/user_events: Move pages/locks into groups to prepare for namespaces") Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-22tracing/hist: add in missing * in comment blocksColin Ian King1-2/+2
There are a couple of missing * in comment blocks. Fix these. Cleans up two clang warnings: kernel/trace/trace_events_hist.c:986: warning: bad line: kernel/trace/trace_events_hist.c:3229: warning: bad line: Link: https://lkml.kernel.org/r/20221020133019.1547587-1-colin.i.king@gmail.com Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-20Merge tag 'trace-probes-v6.1' of ↵Linus Torvalds3-19/+38
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing/probes fixes from Steven Rostedt: - Fix possible NULL pointer dereference on trace_event_file in kprobe_event_gen_test_exit() - Fix NULL pointer dereference for trace_array in kprobe_event_gen_test_exit() - Fix memory leak of filter string for eprobes - Fix a possible memory leak in rethook_alloc() - Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case which can cause a possible use-after-free - Fix warning in eprobe filter creation - Fix eprobe filter creation as it picked the wrong event for the fields * tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/eprobe: Fix eprobe filter to make a filter correctly tracing/eprobe: Fix warning in filter creation kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case rethook: fix a potential memleak in rethook_alloc() tracing/eprobe: Fix memory leak of filter string tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()
2022-11-20tracing: Fix race where eprobes can be called before the eventSteven Rostedt (Google)1-0/+3
The flag that tells the event to call its triggers after reading the event is set for eprobes after the eprobe is enabled. This leads to a race where the eprobe may be triggered at the beginning of the event where the record information is NULL. The eprobe then dereferences the NULL record causing a NULL kernel pointer bug. Test for a NULL record to keep this from happening. Link: https://lore.kernel.org/linux-trace-kernel/20221116192552.1066630-1-rafaelmendsr@gmail.com/ Link: https://lore.kernel.org/linux-trace-kernel/20221117214249.2addbe10@gandalf.local.home Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: stable@vger.kernel.org Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17tracing: Fix potential null-pointer-access of entry in list 'tr->err_log'Zheng Yejian1-4/+5
Entries in list 'tr->err_log' will be reused after entry number exceed TRACING_LOG_ERRS_MAX. The cmd string of the to be reused entry will be freed first then allocated a new one. If the allocation failed, then the entry will still be in list 'tr->err_log' but its 'cmd' field is set to be NULL, later access of 'cmd' is risky. Currently above problem can cause the loss of 'cmd' information of first entry in 'tr->err_log'. When execute `cat /sys/kernel/tracing/error_log`, reproduce logs like: [ 37.495100] trace_kprobe: error: Maxactive is not for kprobe(null) ^ [ 38.412517] trace_kprobe: error: Maxactive is not for kprobe Command: p4:myprobe2 do_sys_openat2 ^ Link: https://lore.kernel.org/linux-trace-kernel/20221114104632.3547266-1-zhengyejian1@huawei.com Fixes: 1581a884b7ca ("tracing: Remove size restriction on tracing_log_err cmd strings") Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17tracing: Remove unused __bad_type_size() methodQiujun Huang1-2/+0
__bad_type_size() is unused after commit 04ae87a52074("ftrace: Rework event_create_dir()"). So, remove it. Link: https://lkml.kernel.org/r/D062EC2E-7DB7-4402-A67E-33C3577F551E@gmail.com Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-18tracing/eprobe: Fix eprobe filter to make a filter correctlyMasami Hiramatsu (Google)1-1/+1
Since the eprobe filter was defined based on the eprobe's trace event itself, it doesn't work correctly. Use the original trace event of the eprobe when making the filter so that the filter works correctly. Without this fix: # echo 'e syscalls/sys_enter_openat \ flags_rename=$flags:u32 if flags < 1000' >> dynamic_events # echo 1 > events/eprobes/sys_enter_openat/enable [ 114.551550] event trace: Could not enable event sys_enter_openat -bash: echo: write error: Invalid argument With this fix: # echo 'e syscalls/sys_enter_openat \ flags_rename=$flags:u32 if flags < 1000' >> dynamic_events # echo 1 > events/eprobes/sys_enter_openat/enable # tail trace cat-241 [000] ...1. 266.498449: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0 cat-242 [000] ...1. 266.977640: sys_enter_openat: (syscalls.sys_enter_openat) flags_rename=0 Link: https://lore.kernel.org/all/166823166395.1385292.8931770640212414483.stgit@devnote3/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com> Tested-by: Rafael Mendonca <rafaelmendsr@gmail.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing/eprobe: Fix warning in filter creationRafael Mendonca1-1/+1
The filter pointer (filterp) passed to create_filter() function must be a pointer that references a NULL pointer, otherwise, we get a warning when adding a filter option to the event probe: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core sched/sched_stat_runtime \ runtime=$runtime:u32 if cpu < 4' >> dynamic_events [ 5034.340439] ------------[ cut here ]------------ [ 5034.341258] WARNING: CPU: 0 PID: 223 at kernel/trace/trace_events_filter.c:1939 create_filter+0x1db/0x250 [...] stripped [ 5034.345518] RIP: 0010:create_filter+0x1db/0x250 [...] stripped [ 5034.351604] Call Trace: [ 5034.351803] <TASK> [ 5034.351959] ? process_preds+0x1b40/0x1b40 [ 5034.352241] ? rcu_read_lock_bh_held+0xd0/0xd0 [ 5034.352604] ? kasan_set_track+0x29/0x40 [ 5034.352904] ? kasan_save_alloc_info+0x1f/0x30 [ 5034.353264] create_event_filter+0x38/0x50 [ 5034.353573] __trace_eprobe_create+0x16f4/0x1d20 [ 5034.353964] ? eprobe_dyn_event_release+0x360/0x360 [ 5034.354363] ? mark_held_locks+0xa6/0xf0 [ 5034.354684] ? _raw_spin_unlock_irqrestore+0x35/0x60 [ 5034.355105] ? trace_hardirqs_on+0x41/0x120 [ 5034.355417] ? _raw_spin_unlock_irqrestore+0x35/0x60 [ 5034.355751] ? __create_object+0x5b7/0xcf0 [ 5034.356027] ? lock_is_held_type+0xaf/0x120 [ 5034.356362] ? rcu_read_lock_bh_held+0xb0/0xd0 [ 5034.356716] ? rcu_read_lock_bh_held+0xd0/0xd0 [ 5034.357084] ? kasan_set_track+0x29/0x40 [ 5034.357411] ? kasan_save_alloc_info+0x1f/0x30 [ 5034.357715] ? __kasan_kmalloc+0xb8/0xc0 [ 5034.357985] ? write_comp_data+0x2f/0x90 [ 5034.358302] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.358691] ? argv_split+0x381/0x460 [ 5034.358949] ? write_comp_data+0x2f/0x90 [ 5034.359240] ? eprobe_dyn_event_release+0x360/0x360 [ 5034.359620] trace_probe_create+0xf6/0x110 [ 5034.359940] ? trace_probe_match_command_args+0x240/0x240 [ 5034.360376] eprobe_dyn_event_create+0x21/0x30 [ 5034.360709] create_dyn_event+0xf3/0x1a0 [ 5034.360983] trace_parse_run_command+0x1a9/0x2e0 [ 5034.361297] ? dyn_event_release+0x500/0x500 [ 5034.361591] dyn_event_write+0x39/0x50 [ 5034.361851] vfs_write+0x311/0xe50 [ 5034.362091] ? dyn_event_seq_next+0x40/0x40 [ 5034.362376] ? kernel_write+0x5b0/0x5b0 [ 5034.362637] ? write_comp_data+0x2f/0x90 [ 5034.362937] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.363258] ? ftrace_syscall_enter+0x544/0x840 [ 5034.363563] ? write_comp_data+0x2f/0x90 [ 5034.363837] ? __sanitizer_cov_trace_pc+0x25/0x60 [ 5034.364156] ? write_comp_data+0x2f/0x90 [ 5034.364468] ? write_comp_data+0x2f/0x90 [ 5034.364770] ksys_write+0x158/0x2a0 [ 5034.365022] ? __ia32_sys_read+0xc0/0xc0 [ 5034.365344] __x64_sys_write+0x7c/0xc0 [ 5034.365669] ? syscall_enter_from_user_mode+0x53/0x70 [ 5034.366084] do_syscall_64+0x60/0x90 [ 5034.366356] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 5034.366767] RIP: 0033:0x7ff0b43938f3 [...] stripped [ 5034.371892] </TASK> [ 5034.374720] ---[ end trace 0000000000000000 ]--- Link: https://lore.kernel.org/all/20221108202148.1020111-1-rafaelmendsr@gmail.com/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18rethook: fix a potential memleak in rethook_alloc()Yi Yang1-1/+3
In rethook_alloc(), the variable rh is not freed or passed out if handler is NULL, which could lead to a memleak, fix it. Link: https://lore.kernel.org/all/20221110104438.88099-1-yiyang13@huawei.com/ [Masami: Add "rethook:" tag to the title.] Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook") Cc: stable@vger.kernel.org Signed-off-by: Yi Yang <yiyang13@huawei.com> Acke-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing/eprobe: Fix memory leak of filter stringRafael Mendonca1-0/+1
The filter string doesn't get freed when a dynamic event is deleted. If a filter is set, then memory is leaked: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events root@localhost:/sys/kernel/tracing# echo "-:egroup/stat_runtime_4core" >> dynamic_events root@localhost:/sys/kernel/tracing# echo scan > /sys/kernel/debug/kmemleak [ 224.416373] kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) root@localhost:/sys/kernel/tracing# cat /sys/kernel/debug/kmemleak unreferenced object 0xffff88810156f1b8 (size 8): comm "bash", pid 224, jiffies 4294935612 (age 55.800s) hex dump (first 8 bytes): 63 70 75 20 3c 20 34 00 cpu < 4. backtrace: [<000000009f880725>] __kmem_cache_alloc_node+0x18e/0x720 [<0000000042492946>] __kmalloc+0x57/0x240 [<0000000034ea7995>] __trace_eprobe_create+0x1214/0x1d30 [<00000000d70ef730>] trace_probe_create+0xf6/0x110 [<00000000915c7b16>] eprobe_dyn_event_create+0x21/0x30 [<000000000d894386>] create_dyn_event+0xf3/0x1a0 [<00000000e9af57d5>] trace_parse_run_command+0x1a9/0x2e0 [<0000000080777f18>] dyn_event_write+0x39/0x50 [<0000000089f0ec73>] vfs_write+0x311/0xe50 [<000000003da1bdda>] ksys_write+0x158/0x2a0 [<00000000bb1e616e>] __x64_sys_write+0x7c/0xc0 [<00000000e8aef1f7>] do_syscall_64+0x60/0x90 [<00000000fe7fe8ba>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Additionally, in __trace_eprobe_create() function, if an error occurs after the call to trace_eprobe_parse_filter(), which allocates the filter string, then memory is also leaked. That can be reproduced by creating the same event probe twice: root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events root@localhost:/sys/kernel/tracing# echo 'e:egroup/stat_runtime_4core \ sched/sched_stat_runtime runtime=$runtime:u32 if cpu < 4' >> dynamic_events -bash: echo: write error: File exists root@localhost:/sys/kernel/tracing# echo scan > /sys/kernel/debug/kmemleak [ 207.871584] kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) root@localhost:/sys/kernel/tracing# cat /sys/kernel/debug/kmemleak unreferenced object 0xffff8881020d17a8 (size 8): comm "bash", pid 223, jiffies 4294938308 (age 31.000s) hex dump (first 8 bytes): 63 70 75 20 3c 20 34 00 cpu < 4. backtrace: [<000000000e4f5f31>] __kmem_cache_alloc_node+0x18e/0x720 [<0000000024f0534b>] __kmalloc+0x57/0x240 [<000000002930a28e>] __trace_eprobe_create+0x1214/0x1d30 [<0000000028387903>] trace_probe_create+0xf6/0x110 [<00000000a80d6a9f>] eprobe_dyn_event_create+0x21/0x30 [<000000007168698c>] create_dyn_event+0xf3/0x1a0 [<00000000f036bf6a>] trace_parse_run_command+0x1a9/0x2e0 [<00000000014bde8b>] dyn_event_write+0x39/0x50 [<0000000078a097f7>] vfs_write+0x311/0xe50 [<00000000996cb208>] ksys_write+0x158/0x2a0 [<00000000a3c2acb0>] __x64_sys_write+0x7c/0xc0 [<0000000006b5d698>] do_syscall_64+0x60/0x90 [<00000000780e8ecf>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix both issues by releasing the filter string in trace_event_probe_cleanup(). Link: https://lore.kernel.org/all/20221108235738.1021467-1-rafaelmendsr@gmail.com/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing: kprobe: Fix potential null-ptr-deref on trace_array in ↵Shang XiaoJing1-0/+4
kprobe_event_gen_test_exit() When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it will goto delete, which will call kprobe_event_delete() and release the corresponding resource. However, the trace_array in gen_kretprobe_test will point to the invalid resource. Set gen_kretprobe_test to NULL after called kprobe_event_delete() to prevent null-ptr-deref. BUG: kernel NULL pointer dereference, address: 0000000000000070 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 246 Comm: modprobe Tainted: G W 6.1.0-rc1-00174-g9522dc5c87da-dirty #248 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0 Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c 01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 <44> 8b 65 70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000 RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064 R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000 FS: 00007f89eeff6540(0000) GS:ffff88813b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __ftrace_set_clr_event+0x3e/0x60 trace_array_set_clr_event+0x35/0x50 ? 0xffffffffa0000000 kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test] __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f89eeb061b7 Link: https://lore.kernel.org/all/20221108015130.28326-3-shangxiaojing@huawei.com/ Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com> Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-18tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in ↵Shang XiaoJing1-16/+28
kprobe_event_gen_test_exit() When trace_get_event_file() failed, gen_kretprobe_test will be assigned as the error code. If module kprobe_event_gen_test is removed now, the null pointer dereference will happen in kprobe_event_gen_test_exit(). Check if gen_kprobe_test or gen_kretprobe_test is error code or NULL before dereference them. BUG: kernel NULL pointer dereference, address: 0000000000000012 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 3 PID: 2210 Comm: modprobe Not tainted 6.1.0-rc1-00171-g2159299a3b74-dirty #217 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:kprobe_event_gen_test_exit+0x1c/0xb5 [kprobe_event_gen_test] Code: Unable to access opcode bytes at 0xffffffff9ffffff2. RSP: 0018:ffffc900015bfeb8 EFLAGS: 00010246 RAX: ffffffffffffffea RBX: ffffffffa0002080 RCX: 0000000000000000 RDX: ffffffffa0001054 RSI: ffffffffa0001064 RDI: ffffffffdfc6349c RBP: ffffffffa0000000 R08: 0000000000000004 R09: 00000000001e95c0 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000800 R13: ffffffffa0002420 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f56b75be540(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff9ffffff2 CR3: 000000010874a006 CR4: 0000000000330ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Link: https://lore.kernel.org/all/20221108015130.28326-2-shangxiaojing@huawei.com/ Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-17tracing: Fix wild-memory-access in register_synth_event()Shang XiaoJing1-3/+2
In register_synth_event(), if set_synth_event_print_fmt() failed, then both trace_remove_event_call() and unregister_trace_event() will be called, which means the trace_event_call will call __unregister_trace_event() twice. As the result, the second unregister will causes the wild-memory-access. register_synth_event set_synth_event_print_fmt failed trace_remove_event_call event_remove if call->event.funcs then __unregister_trace_event (first call) unregister_trace_event __unregister_trace_event (second call) Fix the bug by avoiding to call the second __unregister_trace_event() by checking if the first one is called. general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN PTI KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] CPU: 0 PID: 3807 Comm: modprobe Not tainted 6.1.0-rc1-00186-g76f33a7eedb4 #299 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:unregister_trace_event+0x6e/0x280 Code: 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 0e 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 63 08 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 e2 01 00 00 49 89 2c 24 48 85 ed 74 28 e8 7a 9b RSP: 0018:ffff88810413f370 EFLAGS: 00010a06 RAX: dffffc0000000000 RBX: ffff888105d050b0 RCX: 0000000000000000 RDX: 1bd5a00000000024 RSI: ffff888119e276e0 RDI: ffffffff835a8b20 RBP: dead000000000100 R08: 0000000000000000 R09: fffffbfff0913481 R10: ffffffff8489a407 R11: fffffbfff0913480 R12: dead000000000122 R13: ffff888105d050b8 R14: 0000000000000000 R15: ffff888105d05028 FS: 00007f7823e8d540(0000) GS:ffff888119e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7823e7ebec CR3: 000000010a058002 CR4: 0000000000330ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __create_synth_event+0x1e37/0x1eb0 create_or_delete_synth_event+0x110/0x250 synth_event_run_command+0x2f/0x110 test_gen_synth_cmd+0x170/0x2eb [synth_event_gen_test] synth_event_gen_test_init+0x76/0x9bc [synth_event_gen_test] do_one_initcall+0xdb/0x480 do_init_module+0x1cf/0x680 load_module+0x6a50/0x70a0 __do_sys_finit_module+0x12f/0x1c0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Link: https://lkml.kernel.org/r/20221117012346.22647-3-shangxiaojing@huawei.com Fixes: 4b147936fa50 ("tracing: Add support for 'synthetic' events") Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com> Cc: stable@vger.kernel.org Cc: <mhiramat@kernel.org> Cc: <zanussi@kernel.org> Cc: <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()Shang XiaoJing1-10/+6
test_gen_synth_cmd() only free buf in fail path, hence buf will leak when there is no failure. Add kfree(buf) to prevent the memleak. The same reason and solution in test_empty_synth_event(). unreferenced object 0xffff8881127de000 (size 2048): comm "modprobe", pid 247, jiffies 4294972316 (age 78.756s) hex dump (first 32 bytes): 20 67 65 6e 5f 73 79 6e 74 68 5f 74 65 73 74 20 gen_synth_test 20 70 69 64 5f 74 20 6e 65 78 74 5f 70 69 64 5f pid_t next_pid_ backtrace: [<000000004254801a>] kmalloc_trace+0x26/0x100 [<0000000039eb1cf5>] 0xffffffffa00083cd [<000000000e8c3bc8>] 0xffffffffa00086ba [<00000000c293d1ea>] do_one_initcall+0xdb/0x480 [<00000000aa189e6d>] do_init_module+0x1cf/0x680 [<00000000d513222b>] load_module+0x6a50/0x70a0 [<000000001fd4d529>] __do_sys_finit_module+0x12f/0x1c0 [<00000000b36c4c0f>] do_syscall_64+0x3f/0x90 [<00000000bbf20cf3>] entry_SYSCALL_64_after_hwframe+0x63/0xcd unreferenced object 0xffff8881127df000 (size 2048): comm "modprobe", pid 247, jiffies 4294972324 (age 78.728s) hex dump (first 32 bytes): 20 65 6d 70 74 79 5f 73 79 6e 74 68 5f 74 65 73 empty_synth_tes 74 20 20 70 69 64 5f 74 20 6e 65 78 74 5f 70 69 t pid_t next_pi backtrace: [<000000004254801a>] kmalloc_trace+0x26/0x100 [<00000000d4db9a3d>] 0xffffffffa0008071 [<00000000c31354a5>] 0xffffffffa00086ce [<00000000c293d1ea>] do_one_initcall+0xdb/0x480 [<00000000aa189e6d>] do_init_module+0x1cf/0x680 [<00000000d513222b>] load_module+0x6a50/0x70a0 [<000000001fd4d529>] __do_sys_finit_module+0x12f/0x1c0 [<00000000b36c4c0f>] do_syscall_64+0x3f/0x90 [<00000000bbf20cf3>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Link: https://lkml.kernel.org/r/20221117012346.22647-2-shangxiaojing@huawei.com Cc: <mhiramat@kernel.org> Cc: <zanussi@kernel.org> Cc: <fengguang.wu@intel.com> Cc: stable@vger.kernel.org Fixes: 9fe41efaca08 ("tracing: Add synth event generation test module") Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17ftrace: Fix null pointer dereference in ftrace_add_mod()Xiu Jianfeng1-0/+1
The @ftrace_mod is allocated by kzalloc(), so both the members {prev,next} of @ftrace_mode->list are NULL, it's not a valid state to call list_del(). If kstrdup() for @ftrace_mod->{func|module} fails, it goes to @out_free tag and calls free_ftrace_mod() to destroy @ftrace_mod, then list_del() will write prev->next and next->prev, where null pointer dereference happens. BUG: kernel NULL pointer dereference, address: 0000000000000008 Oops: 0002 [#1] PREEMPT SMP NOPTI Call Trace: <TASK> ftrace_mod_callback+0x20d/0x220 ? do_filp_open+0xd9/0x140 ftrace_process_regex.isra.51+0xbf/0x130 ftrace_regex_write.isra.52.part.53+0x6e/0x90 vfs_write+0xee/0x3a0 ? __audit_filter_op+0xb1/0x100 ? auditd_test_task+0x38/0x50 ksys_write+0xa5/0xe0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Kernel panic - not syncing: Fatal exception So call INIT_LIST_HEAD() to initialize the list member to fix this issue. Link: https://lkml.kernel.org/r/20221116015207.30858-1-xiujianfeng@huawei.com Cc: stable@vger.kernel.org Fixes: 673feb9d76ab ("ftrace: Add :mod: caching infrastructure to trace_array") Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17ring_buffer: Do not deactivate non-existant pagesDaniil Tatianin1-2/+2
rb_head_page_deactivate() expects cpu_buffer to contain a valid list of ->pages, so verify that the list is actually present before calling it. Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. Link: https://lkml.kernel.org/r/20221114143129.3534443-1-d-tatianin@yandex-team.ru Cc: stable@vger.kernel.org Fixes: 77ae365eca895 ("ring-buffer: make lockless") Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17ftrace: Optimize the allocation for mcount entriesWang Wensheng1-1/+1
If we can't allocate this size, try something smaller with half of the size. Its order should be decreased by one instead of divided by two. Link: https://lkml.kernel.org/r/20221109094434.84046-3-wangwensheng4@huawei.com Cc: <mhiramat@kernel.org> Cc: <mark.rutland@arm.com> Cc: stable@vger.kernel.org Fixes: a79008755497d ("ftrace: Allocate the mcount record pages as groups") Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-17ftrace: Fix the possible incorrect kernel messageWang Wensheng1-1/+1
If the number of mcount entries is an integer multiple of ENTRIES_PER_PAGE, the page count showing on the console would be wrong. Link: https://lkml.kernel.org/r/20221109094434.84046-2-wangwensheng4@huawei.com Cc: <mhiramat@kernel.org> Cc: <mark.rutland@arm.com> Cc: stable@vger.kernel.org Fixes: 5821e1b74f0d0 ("function tracing: fix wrong pos computing when read buffer has been fulfilled") Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-16tracing: Fix memory leak in tracing_read_pipe()Wang Yufen1-0/+1
kmemleak reports this issue: unreferenced object 0xffff888105a18900 (size 128): comm "test_progs", pid 18933, jiffies 4336275356 (age 22801.766s) hex dump (first 32 bytes): 25 73 00 90 81 88 ff ff 26 05 00 00 42 01 58 04 %s......&...B.X. 03 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000560143a1>] __kmalloc_node_track_caller+0x4a/0x140 [<000000006af00822>] krealloc+0x8d/0xf0 [<00000000c309be6a>] trace_iter_expand_format+0x99/0x150 [<000000005a53bdb6>] trace_check_vprintf+0x1e0/0x11d0 [<0000000065629d9d>] trace_event_printf+0xb6/0xf0 [<000000009a690dc7>] trace_raw_output_bpf_trace_printk+0x89/0xc0 [<00000000d22db172>] print_trace_line+0x73c/0x1480 [<00000000cdba76ba>] tracing_read_pipe+0x45c/0x9f0 [<0000000015b58459>] vfs_read+0x17b/0x7c0 [<000000004aeee8ed>] ksys_read+0xed/0x1c0 [<0000000063d3d898>] do_syscall_64+0x3b/0x90 [<00000000a06dda7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd iter->fmt alloced in tracing_read_pipe() -> .. ->trace_iter_expand_format(), but not freed, to fix, add free in tracing_release_pipe() Link: https://lkml.kernel.org/r/1667819090-4643-1-git-send-email-wangyufen@huawei.com Cc: stable@vger.kernel.org Fixes: efbbdaa22bb7 ("tracing: Show real address for trace event arguments") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Wang Yufen <wangyufen@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-16ring-buffer: Include dropped pages in counting dirty patchesSteven Rostedt (Google)1-0/+12
The function ring_buffer_nr_dirty_pages() was created to find out how many pages are filled in the ring buffer. There's two running counters. One is incremented whenever a new page is touched (pages_touched) and the other is whenever a page is read (pages_read). The dirty count is the number touched minus the number read. This is used to determine if a blocked task should be woken up if the percentage of the ring buffer it is waiting for is hit. The problem is that it does not take into account dropped pages (when the new writes overwrite pages that were not read). And then the dirty pages will always be greater than the percentage. This makes the "buffer_percent" file inaccurate, as the number of dirty pages end up always being larger than the percentage, event when it's not and this causes user space to be woken up more than it wants to be. Add a new counter to keep track of lost pages, and include that in the accounting of dirty pages so that it is actually accurate. Link: https://lkml.kernel.org/r/20221021123013.55fb6055@gandalf.local.home Fixes: 2c2b0a78b3739 ("ring-buffer: Add percentage of ring buffer full to wake up reader") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-16tracing/ring-buffer: Have polling block on watermarkSteven Rostedt (Google)2-20/+37
Currently the way polling works on the ring buffer is broken. It will return immediately if there's any data in the ring buffer whereas a read will block until the watermark (defined by the tracefs buffer_percent file) is hit. That is, a select() or poll() will return as if there's data available, but then the following read will block. This is broken for the way select()s and poll()s are supposed to work. Have the polling on the ring buffer also block the same way reads and splice does on the ring buffer. Link: https://lkml.kernel.org/r/20221020231427.41be3f26@gandalf.local.home Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Primiano Tucci <primiano@google.com> Cc: stable@vger.kernel.org Fixes: 1e0d6714aceb7 ("ring-buffer: Do not wake up a splice waiter when page is not full") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-11-04tracing: kprobe: Fix memory leak in test_gen_kprobe/kretprobe_cmd()Shang XiaoJing1-11/+7
test_gen_kprobe_cmd() only free buf in fail path, hence buf will leak when there is no failure. Move kfree(buf) from fail path to common path to prevent the memleak. The same reason and solution in test_gen_kretprobe_cmd(). unreferenced object 0xffff888143b14000 (size 2048): comm "insmod", pid 52490, jiffies 4301890980 (age 40.553s) hex dump (first 32 bytes): 70 3a 6b 70 72 6f 62 65 73 2f 67 65 6e 5f 6b 70 p:kprobes/gen_kp 72 6f 62 65 5f 74 65 73 74 20 64 6f 5f 73 79 73 robe_test do_sys backtrace: [<000000006d7b836b>] kmalloc_trace+0x27/0xa0 [<0000000009528b5b>] 0xffffffffa059006f [<000000008408b580>] do_one_initcall+0x87/0x2a0 [<00000000c4980a7e>] do_init_module+0xdf/0x320 [<00000000d775aad0>] load_module+0x3006/0x3390 [<00000000e9a74b80>] __do_sys_finit_module+0x113/0x1b0 [<000000003726480d>] do_syscall_64+0x35/0x80 [<000000003441e93b>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 Link: https://lore.kernel.org/all/20221102072954.26555-1-shangxiaojing@huawei.com/ Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Cc: stable@vger.kernel.org Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-11-04tracing/fprobe: Fix to check whether fprobe is registered correctlyMasami Hiramatsu (Google)1-1/+2
Since commit ab51e1