Commit 50cff898 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 

Pull misc kbuild changes from Michal Marek:
 "Just a few patches on the kbuild.git#misc branch this time:

   - New Coccinelle patch by Nicholas Mc Guire
   - Existing patch fixes by Julia Lawall
   - Minor comment fix by Markus Elfring"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  Coccinelle: flag conditions with no effect
  scripts/coccicheck: Update reference for the corresponding documentation
  Coccinelle: pm_runtime: ensure relevance of pm_runtime reports
  Coccinelle: limit memdup_user transformation to GFP_KERNEL case
parents 84d69848 c8990359

scripts/coccicheck

+1 −1
Original line number Diff line number Diff line 
#!/bin/bash

# Linux kernel coccicheck

#

# Read Documentation/coccinelle.txt

# Read Documentation/dev-tools/coccinelle.rst

#

# This script requires at least spatch

# version 1.0.0-rc11.

scripts/coccinelle/api/memdup_user.cocci

+4 −4
Original line number Diff line number Diff line
@@ -15,11 +15,11 @@ virtual org 
virtual report



@depends on patch@

expression from,to,size,flag;

expression from,to,size;

identifier l1,l2;

@@



-  to = \(kmalloc\|kzalloc\)(size,flag);

-  to = \(kmalloc\|kzalloc\)(size,GFP_KERNEL);

+  to = memdup_user(from,size);

   if (

-      to==NULL
@@ -37,12 +37,12 @@ identifier l1,l2; 
-  }



@r depends on !patch@

expression from,to,size,flag;

expression from,to,size;

position p;

statement S1,S2;

@@



*  to = \(kmalloc@p\|kzalloc@p\)(size,flag);

*  to = \(kmalloc@p\|kzalloc@p\)(size,GFP_KERNEL);

   if (to==NULL || ...) S1

   if (copy_from_user(to, from, size) != 0)

   S2

scripts/coccinelle/api/pm_runtime.cocci

+11 −7
Original line number Diff line number Diff line
@@ -17,9 +17,10 @@ virtual report 


@runtime_bad_err_handle exists@

expression ret;

position p;

@@

(

ret = \(pm_runtime_idle\|

ret@p = \(pm_runtime_idle\|

	pm_runtime_suspend\|

	pm_runtime_autosuspend\|

	pm_runtime_resume\|
@@ -47,12 +48,13 @@ IS_ERR_VALUE(ret) 
//  For context mode

//----------------------------------------------------------



@depends on runtime_bad_err_handle && context@

@depends on context@

identifier pm_runtime_api;

expression ret;

position runtime_bad_err_handle.p;

@@

(

ret = pm_runtime_api(...);

ret@p = pm_runtime_api(...);

...

* IS_ERR_VALUE(ret)

...
@@ -62,12 +64,13 @@ ret = pm_runtime_api(...); 
//  For patch mode

//----------------------------------------------------------



@depends on runtime_bad_err_handle && patch@

@depends on patch@

identifier pm_runtime_api;

expression ret;

position runtime_bad_err_handle.p;

@@

(

ret = pm_runtime_api(...);

ret@p = pm_runtime_api(...);

...

- IS_ERR_VALUE(ret)

+ ret < 0
@@ -78,13 +81,14 @@ ret = pm_runtime_api(...); 
//  For org and report mode

//----------------------------------------------------------



@r depends on runtime_bad_err_handle && (org || report) exists@

@r depends on (org || report) exists@

position p1, p2;

identifier pm_runtime_api;

expression ret;

position runtime_bad_err_handle.p;

@@

(

ret = pm_runtime_api@p1(...);

ret@p = pm_runtime_api@p1(...);

...

IS_ERR_VALUE@p2(ret)

...

scripts/coccinelle/misc/cond_no_effect.cocci

0 → 100644
+64 −0
Original line number Diff line number Diff line 
///Find conditions where if and else branch are functionally

// identical.

//

// There can be false positives in cases where the positional

// information is used (as with lockdep) or where the identity

// is a placeholder for not yet handled cases.

// Unfortunately there also seems to be a tendency to use

// the last if else/else as a "default behavior" - which some

// might consider a legitimate coding pattern. From discussion

// on kernelnewbies though it seems that this is not really an

// accepted pattern and if at all it would need to be commented

//

// In the Linux kernel it does not seem to actually report

// false positives except for those that were documented as

// being intentional.

// the two known cases are:

//   arch/sh/kernel/traps_64.c:read_opcode()

//        } else if ((pc & 1) == 0) {

//              /* SHcompact */

//              /* TODO : provide handling for this.  We don't really support

//                 user-mode SHcompact yet, and for a kernel fault, this would

//                 have to come from a module built for SHcompact.  */

//              return -EFAULT;

//      } else {

//              /* misaligned */

//              return -EFAULT;

//      }

//   fs/kernfs/file.c:kernfs_fop_open()

//       * Both paths of the branch look the same.  They're supposed to

//       * look that way and give @of->mutex different static lockdep keys.

//       */

//      if (has_mmap)

//              mutex_init(&of->mutex);

//      else

//              mutex_init(&of->mutex);

//

// All other cases look like bugs or at least lack of documentation

//

// Confidence: Moderate

// Copyright: (C) 2016 Nicholas Mc Guire, OSADL.  GPLv2.

// Comments:

// Options: --no-includes --include-headers



virtual org

virtual report



@cond@

statement S1;

position p;

@@



* if@p (...) S1 else S1



@script:python depends on org@

p << cond.p;

@@



cocci.print_main("WARNING: possible condition with no effect (if == else)",p)



@script:python depends on report@

p << cond.p;

@@



coccilib.report.print_report(p[0],"WARNING: possible condition with no effect (if == else)")

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