9p: prevent read overrun in protocol dump tracepoint

commit a931c6816078af3e306e0f444f492396ce40de31 upstream.

An out of bounds read can occur within the tracepoint 9p_protocol_dump. In
the fast as

9p: prevent read overrun in protocol dump tracepoint

commit a931c6816078af3e306e0f444f492396ce40de31 upstream.

An out of bounds read can occur within the tracepoint 9p_protocol_dump. In
the fast assign, there is a memcpy that uses a constant size of 32 (macro
named P9_PROTO_DUMP_SZ). When the copy is invoked, the source buffer is not
guaranteed match this size. It was found that in some cases the source
buffer size is less than 32, resulting in a read that overruns.

The size of the source buffer seems to be known at the time of the
tracepoint being invoked. The allocations happen within p9_fcall_init(),
where the capacity field is set to the allocated size of the payload
buffer. This patch tries to fix the overrun by changing the fixed array to
a dynamically sized array and using the minimum of the capacity value or
P9_PROTO_DUMP_SZ as its length. The trace log statement is adjusted to
account for this. Note that the trace log no longer splits the payload on
the first 16 bytes. The full payload is now logged to a single line.

To repro the orignal problem, operations to a plan 9 managed resource can
be used. The simplest approach might just be mounting a shared filesystem
(between host and guest vm) using the plan 9 protocol while the tracepoint
is enabled.

mount -t 9p -o trans=virtio <mount_tag> <mount_path>

The bpftrace program below can be used to show the out of bounds read.
Note that a recent version of bpftrace is needed for the raw tracepoint
support. The script was tested using v0.19.0.

/* from include/net/9p/9p.h */
struct p9_fcall {
u32 size;
u8 id;
u16 tag;
size_t offset;
size_t capacity;
struct kmem_cache *cache;
u8 *sdata;
bool zc;
};

tracepoint:9p:9p_protocol_dump
{
/* out of bounds read can happen when this tracepoint is enabled */
}

rawtracepoint:9p_protocol_dump
{
$pdu = (struct p9_fcall *)arg1;
$dump_sz = (uint64)32;

if ($dump_sz > $pdu->capacity) {
printf("reading %zu bytes from src buffer of %zu bytes\n",
$dump_sz, $pdu->capacity);
}
}

Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Message-ID: <20231204202321.22730-1-inwardvessel@gmail.com>
Fixes: 60ece0833b6c ("net/9p: allocate appropriate reduced message buffers")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

9p fid refcount: add a 9p_fid_ref tracepoint

This adds a tracepoint event for 9p fid lifecycle tracing: when a fid
is created, its reference count increased/decreased, and freed.
The new 9p_fid_ref

9p fid refcount: add a 9p_fid_ref tracepoint

This adds a tracepoint event for 9p fid lifecycle tracing: when a fid
is created, its reference count increased/decreased, and freed.
The new 9p_fid_ref tracepoint should help anyone wishing to debug any
fid problem such as missing clunk (destroy) or use-after-free.

Link: https://lkml.kernel.org/r/20220612085330.1451496-6-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/9p/tracing: Export enums in tracepoints to userspace

The tracepoints in the 9p code use a lot of enums for the __print_symbolic()
function. These enums are shown in the tracepoint format files,

net/9p/tracing: Export enums in tracepoints to userspace

The tracepoints in the 9p code use a lot of enums for the __print_symbolic()
function. These enums are shown in the tracepoint format files, and user
space tools such as trace-cmd does not have the information to parse it.
Add helper macros to export the enums with TRACE_DEFINE_ENUM().

Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org

Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

show more ...

9p: trace: use %*ph to dump buffer

Additionally change cast from long to unsigned long to follow specificator.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Eric

9p: trace: use %*ph to dump buffer

Additionally change cast from long to unsigned long to follow specificator.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

show more ...

net/9p: Convert net/9p protocol dumps to tracepoints

This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or directory
root@qemu-img-

net/9p: Convert net/9p protocol dumps to tracepoints

This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or directory
root@qemu-img-64:~# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
ls-1536 [001] 70.928584: 9p_protocol_dump: clnt 18446612132784021504 P9_TWALK(tag = 1)
000: 16 00 00 00 6e 01 00 01 00 00 00 02 00 00 00 01
010: 00 03 00 31 32 33 00 00 00 ff ff ff ff 00 00 00

ls-1536 [001] 70.928587: <stack trace>
=> trace_9p_protocol_dump
=> p9pdu_finalize
=> p9_client_rpc
=> p9_client_walk
=> v9fs_vfs_lookup
=> d_alloc_and_lookup
=> walk_component
=> path_lookupat
ls-1536 [000] 70.929696: 9p_protocol_dump: clnt 18446612132784021504 P9_RLERROR(tag = 1)
000: 0b 00 00 00 07 01 00 02 00 00 00 4e 03 00 02 00
010: 00 00 00 00 03 00 02 00 00 00 00 00 ff 43 00 00

ls-1536 [000] 70.929697: <stack trace>
=> trace_9p_protocol_dump
=> p9_client_rpc
=> p9_client_walk
=> v9fs_vfs_lookup
=> d_alloc_and_lookup
=> walk_component
=> path_lookupat
=> do_path_lookup

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/9p/tracing: Export enums in tracepoints to userspace

The tracepoints in the 9p code use a lot of enums for the __print_symbolic()
function. These enums are shown in the tracepoint fo

net/9p/tracing: Export enums in tracepoints to userspace

The tracepoints in the 9p code use a lot of enums for the __print_symbolic()
function. These enums are shown in the tracepoint format files, and user
space tools such as trace-cmd does not have the information to parse it.
Add helper macros to export the enums with TRACE_DEFINE_ENUM().

Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org

Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

show more ...

9p: trace: use %*ph to dump buffer

Additionally change cast from long to unsigned long to follow specificator.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

9p: trace: use %*ph to dump buffer

Additionally change cast from long to unsigned long to follow specificator.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

show more ...

net/9p: Convert net/9p protocol dumps to tracepoints

This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or director

net/9p: Convert net/9p protocol dumps to tracepoints

This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or directory
root@qemu-img-64:~# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
ls-1536 [001] 70.928584: 9p_protocol_dump: clnt 18446612132784021504 P9_TWALK(tag = 1)
000: 16 00 00 00 6e 01 00 01 00 00 00 02 00 00 00 01
010: 00 03 00 31 32 33 00 00 00 ff ff ff ff 00 00 00

ls-1536 [001] 70.928587: <stack trace>
=> trace_9p_protocol_dump
=> p9pdu_finalize
=> p9_client_rpc
=> p9_client_walk
=> v9fs_vfs_lookup
=> d_alloc_and_lookup
=> walk_component
=> path_lookupat
ls-1536 [000] 70.929696: 9p_protocol_dump: clnt 18446612132784021504 P9_RLERROR(tag = 1)
000: 0b 00 00 00 07 01 00 02 00 00 00 4e 03 00 02 00
010: 00 00 00 00 03 00 02 00 00 00 00 00 ff 43 00 00

ls-1536 [000] 70.929697: <stack trace>
=> trace_9p_protocol_dump
=> p9_client_rpc
=> p9_client_walk
=> v9fs_vfs_lookup
=> d_alloc_and_lookup
=> walk_component
=> path_lookupat
=> do_path_lookup

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

show more ...