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apparmor: remove dead code

PATCH In review Gustavo A. R. Silva 3 participants 4 messages Aug 23, 2018

Subsystems (2)
Security (LSM) Apparmor security module
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Gustavo A. R. Silva

author
#0 lore raw

PATCH 1/1 apparmor: remove dead code

Due to commit fb5841091f28 ("apparmor: remove no-op permission check in policy_unpack"), there is some leftover code.

Coverity reports this issue as Structurally dead code. Fix this by removing such code.

Addresses-Coverity-ID: 1472998 ("Structurally dead code")

Fixes fb5841091f28 ("apparmor: remove no-op permission check in policy_unpack")
Signed-off-by Gustavo A. R. Silva <[email protected]>
---
 security/apparmor/policy_unpack.c | 4 ----
 1 file changed, 4 deletions(-)
security/apparmor/policy_unpack.c +0 -4
index 3647b58..21cb384 100644
@@ -422,10 +422,6 @@ static struct aa_dfa *unpack_dfa(struct aa_ext *e)
 	}
 
 	return dfa;
-
-fail:
-	aa_put_dfa(dfa);
-	return ERR_PTR(-EPROTO);
 }
 
 /**
Signature · 1 line
2.7.4
maintainer
#1 lore raw

On 08/23/2018 06:42 AM, Gustavo A. R. Silva wrote:

thank you for the patch, but a fix for this issue was pushed to apparmor-next yesterday

Quoted 29 lines

Due to commit fb5841091f28 ("apparmor: remove no-op permission check in policy_unpack"), there is some leftover code.

Coverity reports this issue as Structurally dead code. Fix this by removing such code.

Addresses-Coverity-ID: 1472998 ("Structurally dead code")

Fixes fb5841091f28 ("apparmor: remove no-op permission check in policy_unpack")
Signed-off-by Gustavo A. R. Silva <[email protected]>
---
 security/apparmor/policy_unpack.c | 4 ----
 1 file changed, 4 deletions(-)
security/apparmor/policy_unpack.c +0 -4
index 3647b58..21cb384 100644
@@ -422,10 +422,6 @@ static struct aa_dfa *unpack_dfa(struct aa_ext *e)
 	}
 
 	return dfa;
-
-fail:
-	aa_put_dfa(dfa);
-	return ERR_PTR(-EPROTO);
 }
 
 /**
author
#2 lore raw
Quoted 4 lines · John Johansen

On 08/23/2018 06:42 AM, Gustavo A. R. Silva wrote:

thank you for the patch, but a fix for this issue was pushed to apparmor-next yesterday

That's great. Good to know.

Thanks
--
Gustavo

build bot
#3 lore raw
In reply to Gustavo A. R. Silva
Thank you for the patch! Yet something to improve:

Hi Gustavo,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on security/next]
[also build test ERROR on v4.18 next-20180822]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Gustavo-A-R-Silva/apparmor-remove-dead-code/20180824-005627
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git next
config: i386-randconfig-x079-201833 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386

All errors (new ones prefixed by >>):

security//apparmor/policy_unpack.c: In function 'unpack_dfa':

>> security//apparmor/policy_unpack.c:445:4: error: label 'fail' used but not defined
       goto fail;
       ^~~~

vim +/fail +445 security//apparmor/policy_unpack.c

736ec752d John Johansen 2010-07-29  414  
736ec752d John Johansen 2010-07-29  415  /**
736ec752d John Johansen 2010-07-29  416   * unpack_dfa - unpack a file rule dfa
736ec752d John Johansen 2010-07-29  417   * @e: serialized data extent information (NOT NULL)
736ec752d John Johansen 2010-07-29  418   *
736ec752d John Johansen 2010-07-29  419   * returns dfa or ERR_PTR or NULL if no dfa
736ec752d John Johansen 2010-07-29  420   */
736ec752d John Johansen 2010-07-29  421  static struct aa_dfa *unpack_dfa(struct aa_ext *e)
736ec752d John Johansen 2010-07-29  422  {
736ec752d John Johansen 2010-07-29  423  	char *blob = NULL;
736ec752d John Johansen 2010-07-29  424  	size_t size;
736ec752d John Johansen 2010-07-29  425  	struct aa_dfa *dfa = NULL;
736ec752d John Johansen 2010-07-29  426  
736ec752d John Johansen 2010-07-29  427  	size = unpack_blob(e, &blob, "aadfa");
736ec752d John Johansen 2010-07-29  428  	if (size) {
736ec752d John Johansen 2010-07-29  429  		/*
736ec752d John Johansen 2010-07-29  430  		 * The dfa is aligned with in the blob to 8 bytes
736ec752d John Johansen 2010-07-29  431  		 * from the beginning of the stream.
dd51c8485 John Johansen 2013-07-10  432  		 * alignment adjust needed by dfa unpack
736ec752d John Johansen 2010-07-29  433  		 */
dd51c8485 John Johansen 2013-07-10  434  		size_t sz = blob - (char *) e->start -
dd51c8485 John Johansen 2013-07-10  435  			((e->pos - e->start) & 7);
736ec752d John Johansen 2010-07-29  436  		size_t pad = ALIGN(sz, 8) - sz;
736ec752d John Johansen 2010-07-29  437  		int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
abbf87340 John Johansen 2017-01-16  438  			TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
736ec752d John Johansen 2010-07-29  439  		dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
736ec752d John Johansen 2010-07-29  440  
736ec752d John Johansen 2010-07-29  441  		if (IS_ERR(dfa))
736ec752d John Johansen 2010-07-29  442  			return dfa;
736ec752d John Johansen 2010-07-29  443  
736ec752d John Johansen 2010-07-29  444  		if (!verify_accept(dfa, flags))
736ec752d John Johansen 2010-07-29 @445  			goto fail;
736ec752d John Johansen 2010-07-29  446  	}
736ec752d John Johansen 2010-07-29  447  
736ec752d John Johansen 2010-07-29  448  	return dfa;
736ec752d John Johansen 2010-07-29  449  }
736ec752d John Johansen 2010-07-29  450

:::::: The code at line 445 was first introduced by commit
:::::: 736ec752d95e91e77cc0e8c97c057ab076ac2f51 AppArmor: policy routines for loading and unpacking policy

:::::: TO: John Johansen <[email protected]> :::::: CC: James Morris <[email protected]>

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