<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel/trace/trace_kprobe.c, branch v5.1.10</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.10</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.10'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2019-03-15T21:47:02Z</updated>
<entry>
<title>Merge tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2019-03-15T21:47:02Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-15T21:47:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=aa2e3ac64ace127f403be85aa4d6015b859385f2'/>
<id>urn:sha1:aa2e3ac64ace127f403be85aa4d6015b859385f2</id>
<content type='text'>
Pull tracing fixes and cleanups from Steven Rostedt:
 "This contains a series of last minute clean ups, small fixes and error
  checks"

* tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/probe: Verify alloc_trace_*probe() result
  tracing/probe: Check event/group naming rule at parsing
  tracing/probe: Check the size of argument name and body
  tracing/probe: Check event name length correctly
  tracing/probe: Check maxactive error cases
  tracing: kdb: Fix ftdump to not sleep
  trace/probes: Remove kernel doc style from non kernel doc comment
  tracing/probes: Make reserved_field_names static
</content>
</entry>
<entry>
<title>tracing/probe: Verify alloc_trace_*probe() result</title>
<updated>2019-03-14T23:54:21Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2019-03-14T04:30:50Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a039480e9e93896cadc5a91468964febb3c5d488'/>
<id>urn:sha1:a039480e9e93896cadc5a91468964febb3c5d488</id>
<content type='text'>
Since alloc_trace_*probe() returns -EINVAL only if !event &amp;&amp; !group,
it should not happen in trace_*probe_create(). If we catch that case
there is a bug. So use WARN_ON_ONCE() instead of pr_info().

Link: http://lkml.kernel.org/r/155253785078.14922.16902223633734601469.stgit@devnote2

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing/probe: Check event/group naming rule at parsing</title>
<updated>2019-03-14T23:54:11Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2019-03-14T04:30:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=5b7a96220900e3c3f6fb53908eb4602cda959376'/>
<id>urn:sha1:5b7a96220900e3c3f6fb53908eb4602cda959376</id>
<content type='text'>
Check event and group naming rule at parsing it instead
of allocating probes.

Link: http://lkml.kernel.org/r/155253784064.14922.2336893061156236237.stgit@devnote2

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing/probe: Check maxactive error cases</title>
<updated>2019-03-14T23:53:29Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2019-03-14T04:30:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=287c038c0b994dae7569d96eca154f6a7ff6b4a9'/>
<id>urn:sha1:287c038c0b994dae7569d96eca154f6a7ff6b4a9</id>
<content type='text'>
Check maxactive on kprobe error case, because maxactive
is only for kretprobe, not for kprobe. Also, maxactive
should not be 0, it should be at least 1.

Link: http://lkml.kernel.org/r/155253780952.14922.15784129810238750331.stgit@devnote2

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>trace/probes: Remove kernel doc style from non kernel doc comment</title>
<updated>2019-03-12T15:23:52Z</updated>
<author>
<name>Valdis Klētnieks</name>
<email>valdis.kletnieks@vt.edu</email>
</author>
<published>2019-03-12T08:58:32Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=cede666e2eb28dc8a680d1622fded533769f07a4'/>
<id>urn:sha1:cede666e2eb28dc8a680d1622fded533769f07a4</id>
<content type='text'>
  CC      kernel/trace/trace_kprobe.o
kernel/trace/trace_kprobe.c:41: warning: cannot understand function prototype: 'struct trace_kprobe '

The real problem is that a comment looked like kerneldoc when it shouldn't be...

Link: http://lkml.kernel.org/r/2812.1552381112@turing-police

Signed-off-by: Valdis Kletnieks &lt;valdis.kletnieks@vt.edu&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing/kprobes: Use probe_kernel_read instead of probe_mem_read</title>
<updated>2019-03-01T21:18:15Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2019-02-21T16:16:43Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=49ef5f45701c3dedc6aa6efee5d03756fea0f99d'/>
<id>urn:sha1:49ef5f45701c3dedc6aa6efee5d03756fea0f99d</id>
<content type='text'>
Use probe_kernel_read() instead of probe_mem_read() because
probe_mem_read() is a kind of wrapper for switching memory
read function between uprobes and kprobes.

Link: http://lkml.kernel.org/r/20190222011643.3e19ade84a3db3e83518648f@kernel.org

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>kprobe: Do not use uaccess functions to access kernel memory that can fault</title>
<updated>2019-02-15T17:41:23Z</updated>
<author>
<name>Changbin Du</name>
<email>changbin.du@gmail.com</email>
</author>
<published>2019-01-25T15:10:50Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2c4f1fcbef0bc324830bc2fb1a264c08ec93dec5'/>
<id>urn:sha1:2c4f1fcbef0bc324830bc2fb1a264c08ec93dec5</id>
<content type='text'>
The userspace can ask kprobe to intercept strings at any memory address,
including invalid kernel address. In this case, fetch_store_strlen()
would crash since it uses general usercopy function, and user access
functions are no longer allowed to access kernel memory.

For example, we can crash the kernel by doing something as below:

$ sudo kprobe 'p:do_sys_open +0(+0(%si)):string'

[  103.620391] BUG: GPF in non-whitelisted uaccess (non-canonical address?)
[  103.622104] general protection fault: 0000 [#1] SMP PTI
[  103.623424] CPU: 10 PID: 1046 Comm: cat Not tainted 5.0.0-rc3-00130-gd73aba1-dirty #96
[  103.625321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-2-g628b2e6-dirty-20190104_103505-linux 04/01/2014
[  103.628284] RIP: 0010:process_fetch_insn+0x1ab/0x4b0
[  103.629518] Code: 10 83 80 28 2e 00 00 01 31 d2 31 ff 48 8b 74 24 28 eb 0c 81 fa ff 0f 00 00 7f 1c 85 c0 75 18 66 66 90 0f ae e8 48 63
 ca 89 f8 &lt;8a&gt; 0c 31 66 66 90 83 c2 01 84 c9 75 dc 89 54 24 34 89 44 24 28 48
[  103.634032] RSP: 0018:ffff88845eb37ce0 EFLAGS: 00010246
[  103.635312] RAX: 0000000000000000 RBX: ffff888456c4e5a8 RCX: 0000000000000000
[  103.637057] RDX: 0000000000000000 RSI: 2e646c2f6374652f RDI: 0000000000000000
[  103.638795] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[  103.640556] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
[  103.642297] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  103.644040] FS:  0000000000000000(0000) GS:ffff88846f000000(0000) knlGS:0000000000000000
[  103.646019] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  103.647436] CR2: 00007ffc79758038 CR3: 0000000463360006 CR4: 0000000000020ee0
[  103.649147] Call Trace:
[  103.649781]  ? sched_clock_cpu+0xc/0xa0
[  103.650747]  ? do_sys_open+0x5/0x220
[  103.651635]  kprobe_trace_func+0x303/0x380
[  103.652645]  ? do_sys_open+0x5/0x220
[  103.653528]  kprobe_dispatcher+0x45/0x50
[  103.654682]  ? do_sys_open+0x1/0x220
[  103.655875]  kprobe_ftrace_handler+0x90/0xf0
[  103.657282]  ftrace_ops_assist_func+0x54/0xf0
[  103.658564]  ? __call_rcu+0x1dc/0x280
[  103.659482]  0xffffffffc00000bf
[  103.660384]  ? __ia32_sys_open+0x20/0x20
[  103.661682]  ? do_sys_open+0x1/0x220
[  103.662863]  do_sys_open+0x5/0x220
[  103.663988]  do_syscall_64+0x60/0x210
[  103.665201]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  103.666862] RIP: 0033:0x7fc22fadccdd
[  103.668034] Code: 48 89 54 24 e0 41 83 e2 40 75 32 89 f0 25 00 00 41 00 3d 00 00 41 00 74 24 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff
 ff 0f 05 &lt;48&gt; 3d 00 f0 ff ff 77 33 f3 c3 66 0f 1f 84 00 00 00 00 00 48 8d 44
[  103.674029] RSP: 002b:00007ffc7972c3a8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
[  103.676512] RAX: ffffffffffffffda RBX: 0000562f86147a21 RCX: 00007fc22fadccdd
[  103.678853] RDX: 0000000000080000 RSI: 00007fc22fae1428 RDI: 00000000ffffff9c
[  103.681151] RBP: ffffffffffffffff R08: 0000000000000000 R09: 0000000000000000
[  103.683489] R10: 0000000000000000 R11: 0000000000000287 R12: 00007fc22fce90a8
[  103.685774] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
[  103.688056] Modules linked in:
[  103.689131] ---[ end trace 43792035c28984a1 ]---

This can be fixed by using probe_mem_read() instead, as it can handle faulting
kernel memory addresses, which kprobes can legitimately do.

Link: http://lkml.kernel.org/r/20190125151051.7381-1-changbin.du@gmail.com

Cc: stable@vger.kernel.org
Fixes: 9da3f2b7405 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses")
Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()</title>
<updated>2019-01-15T16:33:45Z</updated>
<author>
<name>Andrea Righi</name>
<email>righi.andrea@gmail.com</email>
</author>
<published>2019-01-11T06:01:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8b05a3a7503c2a982c9c462eae96cfbd59506783'/>
<id>urn:sha1:8b05a3a7503c2a982c9c462eae96cfbd59506783</id>
<content type='text'>
It is possible to trigger a NULL pointer dereference by writing an
incorrectly formatted string to krpobe_events (trying to create a
kretprobe omitting the symbol).

Example:

 echo "r:event_1 " &gt;&gt; /sys/kernel/debug/tracing/kprobe_events

That triggers this:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 #PF error: [normal kernel read fault]
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP PTI
 CPU: 6 PID: 1757 Comm: bash Not tainted 5.0.0-rc1+ #125
 Hardware name: Dell Inc. XPS 13 9370/0F6P3V, BIOS 1.5.1 08/09/2018
 RIP: 0010:kstrtoull+0x2/0x20
 Code: 28 00 00 00 75 17 48 83 c4 18 5b 41 5c 5d c3 b8 ea ff ff ff eb e1 b8 de ff ff ff eb da e8 d6 36 bb ff 66 0f 1f 44 00 00 31 c0 &lt;80&gt; 3f 2b 55 48 89 e5 0f 94 c0 48 01 c7 e8 5c ff ff ff 5d c3 66 2e
 RSP: 0018:ffffb5d482e57cb8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82b12720
 RDX: ffffb5d482e57cf8 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffffb5d482e57d70 R08: ffffa0c05e5a7080 R09: ffffa0c05e003980
 R10: 0000000000000000 R11: 0000000040000000 R12: ffffa0c04fe87b08
 R13: 0000000000000001 R14: 000000000000000b R15: ffffa0c058d749e1
 FS:  00007f137c7f7740(0000) GS:ffffa0c05e580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000000497d46004 CR4: 00000000003606e0
 Call Trace:
  ? trace_kprobe_create+0xb6/0x840
  ? _cond_resched+0x19/0x40
  ? _cond_resched+0x19/0x40
  ? __kmalloc+0x62/0x210
  ? argv_split+0x8f/0x140
  ? trace_kprobe_create+0x840/0x840
  ? trace_kprobe_create+0x840/0x840
  create_or_delete_trace_kprobe+0x11/0x30
  trace_run_command+0x50/0x90
  trace_parse_run_command+0xc1/0x160
  probes_write+0x10/0x20
  __vfs_write+0x3a/0x1b0
  ? apparmor_file_permission+0x1a/0x20
  ? security_file_permission+0x31/0xf0
  ? _cond_resched+0x19/0x40
  vfs_write+0xb1/0x1a0
  ksys_write+0x55/0xc0
  __x64_sys_write+0x1a/0x20
  do_syscall_64+0x5a/0x120
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix by doing the proper argument checks in trace_kprobe_create().

Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Link: https://lore.kernel.org/lkml/20190111095108.b79a2ee026185cbd62365977@kernel.org
Link: http://lkml.kernel.org/r/20190111060113.GA22841@xps-13
Fixes: 6212dd29683e ("tracing/kprobes: Use dyn_event framework for kprobe events")
Acked-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Andrea Righi &lt;righi.andrea@gmail.com&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2018-12-31T19:46:59Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-12-31T19:46:59Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=495d714ad140e1732e66c45d0409054b24c1a0d6'/>
<id>urn:sha1:495d714ad140e1732e66c45d0409054b24c1a0d6</id>
<content type='text'>
Pull tracing updates from Steven Rostedt:

 - Rework of the kprobe/uprobe and synthetic events to consolidate all
   the dynamic event code. This will make changes in the future easier.

 - Partial rewrite of the function graph tracing infrastructure. This
   will allow for multiple users of hooking onto functions to get the
   callback (return) of the function. This is the ground work for having
   kprobes and function graph tracer using one code base.

 - Clean up of the histogram code that will facilitate adding more
   features to the histograms in the future.

 - Addition of str_has_prefix() and a few use cases. There currently is
   a similar function strstart() that is used in a few places, but only
   returns a bool and not a length. These instances will be removed in
   the future to use str_has_prefix() instead.

 - A few other various clean ups as well.

* tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
  tracing: Use the return of str_has_prefix() to remove open coded numbers
  tracing: Have the historgram use the result of str_has_prefix() for len of prefix
  tracing: Use str_has_prefix() instead of using fixed sizes
  tracing: Use str_has_prefix() helper for histogram code
  string.h: Add str_has_prefix() helper function
  tracing: Make function ‘ftrace_exports’ static
  tracing: Simplify printf'ing in seq_print_sym
  tracing: Avoid -Wformat-nonliteral warning
  tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
  tracing: Add hist trigger comments for variable-related fields
  tracing: Remove hist trigger synth_var_refs
  tracing: Use hist trigger's var_ref array to destroy var_refs
  tracing: Remove open-coding of hist trigger var_ref management
  tracing: Use var_refs[] for hist trigger reference checking
  tracing: Change strlen to sizeof for hist trigger static strings
  tracing: Remove unnecessary hist trigger struct field
  tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
  seq_buf: Use size_t for len in seq_buf_puts()
  seq_buf: Make seq_buf_puts() null-terminate the buffer
  arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
  ...
</content>
</entry>
<entry>
<title>tracing: Consolidate trace_add/remove_event_call back to the nolock functions</title>
<updated>2018-12-10T17:22:10Z</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2018-12-04T18:35:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7e1413edd6194a9807aa5f3ac0378b9b4b9da879'/>
<id>urn:sha1:7e1413edd6194a9807aa5f3ac0378b9b4b9da879</id>
<content type='text'>
The trace_add/remove_event_call_nolock() functions were added to allow
the tace_add/remove_event_call() code be called when the event_mutex
lock was already taken. Now that all callers are done within the
event_mutex, there's no reason to have two different interfaces.

Remove the current wrapper trace_add/remove_event_call()s and rename the
_nolock versions back to the original names.

Link: http://lkml.kernel.org/r/154140866955.17322.2081425494660638846.stgit@devbox

Acked-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
