<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/s390/kernel/debug.c, branch v5.14</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>s390/debug: Remove pointer obfuscation</title>
<updated>2021-06-18T14:41:19+00:00</updated>
<author>
<name>Peter Oberparleiter</name>
<email>oberpar@linux.ibm.com</email>
</author>
<published>2021-06-09T12:05:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d2beeb3bc74ec897ced7309c3a104fa4b3be0ac3'/>
<id>d2beeb3bc74ec897ced7309c3a104fa4b3be0ac3</id>
<content type='text'>
When read via debugfs, s390dbf debug-views print the kernel address of
the call-site that created a trace entry. The kernel's %p pointer
hashing feature obfuscates this address, and commit 860ec7c6e21c
("s390/debug: use pK for kernel pointers") made this obfuscation
configurable via the kptr_restrict sysctl.

Obfuscation of kernel address data printed via s390dbf debug-views does
not add any additional protection since the associated debugfs files are
only accessible to the root user that typically has enough other means
to obtain kernel address data.

Also trace payload data may contain binary representations of kernel
addresses as part of logged data structues. Requiring such payload data
to be obfuscated as well would be impractical and greatly diminish the
use of s390dbf.

Therefore completely remove pointer obfuscation from s390dbf
debug-views.

Reviewed-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Peter Oberparleiter &lt;oberpar@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When read via debugfs, s390dbf debug-views print the kernel address of
the call-site that created a trace entry. The kernel's %p pointer
hashing feature obfuscates this address, and commit 860ec7c6e21c
("s390/debug: use pK for kernel pointers") made this obfuscation
configurable via the kptr_restrict sysctl.

Obfuscation of kernel address data printed via s390dbf debug-views does
not add any additional protection since the associated debugfs files are
only accessible to the root user that typically has enough other means
to obtain kernel address data.

Also trace payload data may contain binary representations of kernel
addresses as part of logged data structues. Requiring such payload data
to be obfuscated as well would be impractical and greatly diminish the
use of s390dbf.

Therefore completely remove pointer obfuscation from s390dbf
debug-views.

Reviewed-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Peter Oberparleiter &lt;oberpar@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/debug: use union tod_clock</title>
<updated>2021-02-13T16:17:54+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2021-02-08T15:32:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d1deda6f2b238bfcd3a4521b3221974443416342'/>
<id>d1deda6f2b238bfcd3a4521b3221974443416342</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/debug: debug feature version 3</title>
<updated>2020-08-11T16:16:43+00:00</updated>
<author>
<name>Mikhail Zaslonko</name>
<email>zaslonko@linux.ibm.com</email>
</author>
<published>2020-05-05T08:34:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0990d836cecb207071492f5679d5b07b26574205'/>
<id>0990d836cecb207071492f5679d5b07b26574205</id>
<content type='text'>
Change __debug_entry structure in the following way:
 - remove redundant union
 - Field containing cpuid is expanded to 16 bits. 8-bit width was not
   enough since we already support up to 512 cpus.
 - Field containing the timestamp is expanded to 60 bits. The timestamp
   itself is now stored in the absolute Unix time format in microseconds
   taking the Epoch Index into acount.
Adjust default header for debug entries by setting minimum width for cpuid
to 4 digits.

Reviewed-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Mikhail Zaslonko &lt;zaslonko@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Change __debug_entry structure in the following way:
 - remove redundant union
 - Field containing cpuid is expanded to 16 bits. 8-bit width was not
   enough since we already support up to 512 cpus.
 - Field containing the timestamp is expanded to 60 bits. The timestamp
   itself is now stored in the absolute Unix time format in microseconds
   taking the Epoch Index into acount.
Adjust default header for debug entries by setting minimum width for cpuid
to 4 digits.

Reviewed-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Mikhail Zaslonko &lt;zaslonko@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/debug: remove raw view</title>
<updated>2020-06-29T14:32:20+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2020-06-18T05:09:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ecb1ff6833c461ea3bcf16396cd4f1eb50b119c2'/>
<id>ecb1ff6833c461ea3bcf16396cd4f1eb50b119c2</id>
<content type='text'>
There is not a single user of the debug raw view. Therefore remove it
before anybody uses it. If anybody would make use of the view it would
expose the struct __debug_entry definition to userspace and really
would make it uapi. This wouldn't be good, since the definition is
suboptimal and needs to be changed.

Right now the structure definition is only defined to be uapi, however
there is no user.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is not a single user of the debug raw view. Therefore remove it
before anybody uses it. If anybody would make use of the view it would
expose the struct __debug_entry definition to userspace and really
would make it uapi. This wouldn't be good, since the definition is
suboptimal and needs to be changed.

Right now the structure definition is only defined to be uapi, however
there is no user.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/debug: avoid kernel warning on too large number of pages</title>
<updated>2020-06-23T12:05:55+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2020-03-31T09:57:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=827c4913923e0b441ba07ba4cc41e01181102303'/>
<id>827c4913923e0b441ba07ba4cc41e01181102303</id>
<content type='text'>
When specifying insanely large debug buffers a kernel warning is
printed. The debug code does handle the error gracefully, though.
Instead of duplicating the check let us silence the warning to
avoid crashes when panic_on_warn is used.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Reviewed-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When specifying insanely large debug buffers a kernel warning is
printed. The debug code does handle the error gracefully, though.
Instead of duplicating the check let us silence the warning to
avoid crashes when panic_on_warn is used.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Reviewed-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sysctl: pass kernel pointers to -&gt;proc_handler</title>
<updated>2020-04-27T06:07:40+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2020-04-24T06:43:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=32927393dc1ccd60fb2bdc05b9e8e88753761469'/>
<id>32927393dc1ccd60fb2bdc05b9e8e88753761469</id>
<content type='text'>
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Andrey Ignatov &lt;rdna@fb.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Andrey Ignatov &lt;rdna@fb.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>docs: s390: unify and update s390dbf kdocs at debug.c</title>
<updated>2019-07-05T11:42:22+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2019-07-03T10:19:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0328e519a726ff6e4abacba838eb00415171c34b'/>
<id>0328e519a726ff6e4abacba838eb00415171c34b</id>
<content type='text'>
For non-static-inlines, debug.c already had non-compliant function
header docs. So move the pure prototype kdocs of
("s390: include/asm/debug.h add kerneldoc markups")
from debug.h to debug.c and merge them with the old function docs.
Also, I had the impression that kdoc typically is at the implementation
in the compile unit rather than at the prototype in the header file.

While at it, update the short kdoc description to distinguish the
different functions. And a few more consistency cleanups.

Added a new kdoc for debug_set_critical() since debug.h comments it
as part of the API.

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Acked-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Message-Id: &lt;1562149189-1417-3-git-send-email-maier@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For non-static-inlines, debug.c already had non-compliant function
header docs. So move the pure prototype kdocs of
("s390: include/asm/debug.h add kerneldoc markups")
from debug.h to debug.c and merge them with the old function docs.
Also, I had the impression that kdoc typically is at the implementation
in the compile unit rather than at the prototype in the header file.

While at it, update the short kdoc description to distinguish the
different functions. And a few more consistency cleanups.

Added a new kdoc for debug_set_critical() since debug.h comments it
as part of the API.

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Acked-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Message-Id: &lt;1562149189-1417-3-git-send-email-maier@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390: no need to check return value of debugfs_create functions</title>
<updated>2019-01-28T14:58:55+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2019-01-22T15:21:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7dd541a3fb34b34f0f25154dd0d24d0d9b1ca0f3'/>
<id>7dd541a3fb34b34f0f25154dd0d24d0d9b1ca0f3</id>
<content type='text'>
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: kmalloc() -&gt; kmalloc_array()</title>
<updated>2018-06-12T23:19:22+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2018-06-12T20:55:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6da2ec56059c3c7a7e5f729e6349e74ace1e5c57'/>
<id>6da2ec56059c3c7a7e5f729e6349e74ace1e5c57</id>
<content type='text'>
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/debug: use pK for kernel pointers</title>
<updated>2017-11-24T13:28:34+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2017-11-23T18:26:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=860ec7c6e21cecca8c508a66ee211b56d87f5bd7'/>
<id>860ec7c6e21cecca8c508a66ee211b56d87f5bd7</id>
<content type='text'>
the s390 debug feature (/sys/kernel/debug/s390dbf/) shows the kernel
pointer of the calling function even for kptr_restrict == 2. Let us
use pK instead of p.

This hides the kernel addresses for kptr_restrict == 2:

root@host $ echo 2 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 0000000000000000  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

root@host $ echo 1 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 000000000071171c  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

root@host $ echo 0 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 000000000071171c  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
the s390 debug feature (/sys/kernel/debug/s390dbf/) shows the kernel
pointer of the calling function even for kptr_restrict == 2. Let us
use pK instead of p.

This hides the kernel addresses for kptr_restrict == 2:

root@host $ echo 2 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 0000000000000000  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

root@host $ echo 1 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 000000000071171c  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

root@host $ echo 0 &gt;  /proc/sys/kernel/kptr_restrict
root@host $ tail -n1  /sys/kernel/debug/s390dbf/cio_msg/sprintf
00 01511461280:386645 2 - 00 000000000071171c  snsid: device 0.0.3f68: rc=0 3990/e9 3390/0c

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
