linux-stable.git/kernel/trace, branch v6.0.11 Linux kernel stable tree bpf: Prevent bpf program recursion for raw tracepoint probes 2022-11-26T08:27:56+00:00 Jiri Olsa jolsa@kernel.org 2022-09-16T07:19:14+00:00 2e5399879024fedd6cdc41f73fbf9bbe7208f899 commit 05b24ff9b2cfabfcfd951daaa915a036ab53c9e1 upstream. We got report from sysbot [1] about warnings that were caused by bpf program attached to contention_begin raw tracepoint triggering the same tracepoint by using bpf_trace_printk helper that takes trace_printk_lock lock. Call Trace: <TASK> ? trace_event_raw_event_bpf_trace_printk+0x5f/0x90 bpf_trace_printk+0x2b/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 __unfreeze_partials+0x5b/0x160 ... The can be reproduced by attaching bpf program as raw tracepoint on contention_begin tracepoint. The bpf prog calls bpf_trace_printk helper. Then by running perf bench the spin lock code is forced to take slow path and call contention_begin tracepoint. Fixing this by skipping execution of the bpf program if it's already running, Using bpf prog 'active' field, which is being currently used by trampoline programs for the same reason. Moving bpf_prog_inc_misses_counter to syscall.c because trampoline.c is compiled in just for CONFIG_BPF_JIT option. Reviewed-by: Stanislav Fomichev <sdf@google.com> Reported-by: syzbot+2251879aa068ad9c960d@syzkaller.appspotmail.com [1] https://lore.kernel.org/bpf/YxhFe3EwqchC%2FfYf@krava/T/#t Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20220916071914.7156-1-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 05b24ff9b2cfabfcfd951daaa915a036ab53c9e1 upstream.

We got report from sysbot [1] about warnings that were caused by
bpf program attached to contention_begin raw tracepoint triggering
the same tracepoint by using bpf_trace_printk helper that takes
trace_printk_lock lock.

 Call Trace:
  <TASK>
  ? trace_event_raw_event_bpf_trace_printk+0x5f/0x90
  bpf_trace_printk+0x2b/0xe0
  bpf_prog_a9aec6167c091eef_prog+0x1f/0x24
  bpf_trace_run2+0x26/0x90
  native_queued_spin_lock_slowpath+0x1c6/0x2b0
  _raw_spin_lock_irqsave+0x44/0x50
  bpf_trace_printk+0x3f/0xe0
  bpf_prog_a9aec6167c091eef_prog+0x1f/0x24
  bpf_trace_run2+0x26/0x90
  native_queued_spin_lock_slowpath+0x1c6/0x2b0
  _raw_spin_lock_irqsave+0x44/0x50
  bpf_trace_printk+0x3f/0xe0
  bpf_prog_a9aec6167c091eef_prog+0x1f/0x24
  bpf_trace_run2+0x26/0x90
  native_queued_spin_lock_slowpath+0x1c6/0x2b0
  _raw_spin_lock_irqsave+0x44/0x50
  bpf_trace_printk+0x3f/0xe0
  bpf_prog_a9aec6167c091eef_prog+0x1f/0x24
  bpf_trace_run2+0x26/0x90
  native_queued_spin_lock_slowpath+0x1c6/0x2b0
  _raw_spin_lock_irqsave+0x44/0x50
  __unfreeze_partials+0x5b/0x160
  ...

The can be reproduced by attaching bpf program as raw tracepoint on
contention_begin tracepoint. The bpf prog calls bpf_trace_printk
helper. Then by running perf bench the spin lock code is forced to
take slow path and call contention_begin tracepoint.

Fixing this by skipping execution of the bpf program if it's
already running, Using bpf prog 'active' field, which is being
currently used by trampoline programs for the same reason.

Moving bpf_prog_inc_misses_counter to syscall.c because
trampoline.c is compiled in just for CONFIG_BPF_JIT option.

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Reported-by: syzbot+2251879aa068ad9c960d@syzkaller.appspotmail.com
[1] https://lore.kernel.org/bpf/YxhFe3EwqchC%2FfYf@krava/T/#t
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20220916071914.7156-1-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: Fix potential null-pointer-access of entry in list 'tr->err_log' 2022-11-26T08:27:54+00:00 Zheng Yejian zhengyejian1@huawei.com 2022-11-14T10:46:32+00:00 76f9434d2faa56c8458b2432361760407fdab3b8 [ Upstream commit 067df9e0ad48a97382ab2179bbe773a13a846028 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 067df9e0ad48a97382ab2179bbe773a13a846028 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ring-buffer: Include dropped pages in counting dirty patches 2022-11-26T08:27:53+00:00 Steven Rostedt (Google) rostedt@goodmis.org 2022-10-21T16:30:13+00:00 d372ea508f9a10819136e20158e50eda7b7aaf70 [ Upstream commit 31029a8b2c7e656a0289194ef16415050ae4c4ac ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 31029a8b2c7e656a0289194ef16415050ae4c4ac ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
rethook: fix a potential memleak in rethook_alloc() 2022-11-26T08:27:42+00:00 Yi Yang yiyang13@huawei.com 2022-11-18T01:15:34+00:00 cbc5d1f9a8cc40ba2bc6779b36d2ea1f65bc027c commit 0a1ebe35cb3b7aa1f4b26b37e2a0b9ae68dc4ffb upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0a1ebe35cb3b7aa1f4b26b37e2a0b9ae68dc4ffb upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() 2022-11-26T08:27:41+00:00 Shang XiaoJing shangxiaojing@huawei.com 2022-11-18T01:15:34+00:00 510c12f93674ea0a1423b24f36c67357168a262a commit 22ea4ca9631eb137e64e5ab899e9c89cb6670959 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 22ea4ca9631eb137e64e5ab899e9c89cb6670959 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit() 2022-11-26T08:27:41+00:00 Shang XiaoJing shangxiaojing@huawei.com 2022-11-18T01:15:33+00:00 fd0efd4f7bfe611a8339ba01bc2ac3c33e79159d commit e0d75267f59d7084e0468bd68beeb1bf9c71d7c0 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e0d75267f59d7084e0468bd68beeb1bf9c71d7c0 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: Fix race where eprobes can be called before the event 2022-11-26T08:27:41+00:00 Steven Rostedt (Google) rostedt@goodmis.org 2022-11-18T02:42:49+00:00 73f5191467ffe3af82f27fe0ea6a8c2fac724d3f commit 94eedf3dded5fb472ce97bfaf3ac1c6c29c35d26 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 94eedf3dded5fb472ce97bfaf3ac1c6c29c35d26 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: Fix wild-memory-access in register_synth_event() 2022-11-26T08:27:41+00:00 Shang XiaoJing shangxiaojing@huawei.com 2022-11-17T01:23:46+00:00 a5bfa53e5036b3e7a80be902dd3719a930accabd commit 1b5f1c34d3f5a664a57a5a7557a50e4e3cc2505c upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1b5f1c34d3f5a664a57a5a7557a50e4e3cc2505c upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event() 2022-11-26T08:27:41+00:00 Shang XiaoJing shangxiaojing@huawei.com 2022-11-17T01:23:45+00:00 0e5baaa181a052d968701bb9c5b1d55847f00942 commit a4527fef9afe5c903c718d0cd24609fe9c754250 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a4527fef9afe5c903c718d0cd24609fe9c754250 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tracing/ring-buffer: Have polling block on watermark 2022-11-26T08:27:41+00:00 Steven Rostedt (Google) rostedt@goodmis.org 2022-10-21T03:14:27+00:00 d2d1499f68449cbe8a9d093bb3a14efade0e8d03 commit 42fb0a1e84ff525ebe560e2baf9451ab69127e2b upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 42fb0a1e84ff525ebe560e2baf9451ab69127e2b upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>