[PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure

[PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure

[Jim Meyering]

* Incremental.c (Incremental): On sysfs_read failure, don't call
sysfs_free(sra) just before "goto out_unlock", since that very
same "sra" is freed the same way by the clean-up code below.
---
FYI, coverity spotted the double free.

 Incremental.c |    1 -
 1 file changed, 1 deletion(-)

diff --git a/Incremental.c b/Incremental.c
index 78c9712..4ab9747 100644
--- a/Incremental.c
+++ b/Incremental.c
@@ -326,7 +326,6 @@ int Incremental(char *devname, int verbose, int runstop,
 			fprintf(stderr, Name
 		      ": You have an old buggy kernel which cannot support\n"
 				"      --incremental reliably.  Aborting.\n");
-			sysfs_free(sra);
 			rv = 2;
 			goto out_unlock;
 		}
--
1.7.9.1.266.g24ee9

Re: [PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure

[Jim Meyering]

Jim Meyering wrote:
> * Incremental.c (Incremental): On sysfs_read failure, don't call
> sysfs_free(sra) just before "goto out_unlock", since that very
> same "sra" is freed the same way by the clean-up code below.

Here it is again, but with the Signed-off-by line:

From 981af2b292448a9daa56af86b4c514ad9339665a Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering@redhat.com>
Date: Tue, 21 Feb 2012 11:08:25 +0100
Subject: [PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure

* Incremental.c (Incremental): On sysfs_read failure, don't call
sysfs_free(sra) just before "goto out_unlock", since that very
same "sra" is freed the same way by the clean-up code below.

Signed-off-by: Jim Meyering <meyering@redhat.com>
---
 Incremental.c |    1 -
 1 file changed, 1 deletion(-)

diff --git a/Incremental.c b/Incremental.c
index b457bf3..836a6f1 100644
--- a/Incremental.c
+++ b/Incremental.c
@@ -325,7 +325,6 @@ int Incremental(char *devname, int verbose, int runstop,
 			fprintf(stderr, Name
 		      ": You have an old buggy kernel which cannot support\n"
 				"      --incremental reliably.  Aborting.\n");
-			sysfs_free(sra);
 			rv = 2;
 			goto out_unlock;
 		}
--
1.7.9.1.266.g24ee9

Re: [PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure

[NeilBrown]

[-- Attachment #1: Type: text/plain, Size: 1432 bytes --]

On Tue, 21 Feb 2012 14:02:22 +0100 Jim Meyering <jim@meyering.net> wrote:

> Jim Meyering wrote:
> > * Incremental.c (Incremental): On sysfs_read failure, don't call
> > sysfs_free(sra) just before "goto out_unlock", since that very
> > same "sra" is freed the same way by the clean-up code below.
> 
> Here it is again, but with the Signed-off-by line:
> 
> >From 981af2b292448a9daa56af86b4c514ad9339665a Mon Sep 17 00:00:00 2001
> From: Jim Meyering <meyering@redhat.com>
> Date: Tue, 21 Feb 2012 11:08:25 +0100
> Subject: [PATCH] avoid double-free upon "old buggy kernel" sysfs_read failure
> 
> * Incremental.c (Incremental): On sysfs_read failure, don't call
> sysfs_free(sra) just before "goto out_unlock", since that very
> same "sra" is freed the same way by the clean-up code below.
> 
> Signed-off-by: Jim Meyering <meyering@redhat.com>
> ---
>  Incremental.c |    1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/Incremental.c b/Incremental.c
> index b457bf3..836a6f1 100644
> --- a/Incremental.c
> +++ b/Incremental.c
> @@ -325,7 +325,6 @@ int Incremental(char *devname, int verbose, int runstop,
>  			fprintf(stderr, Name
>  		      ": You have an old buggy kernel which cannot support\n"
>  				"      --incremental reliably.  Aborting.\n");
> -			sysfs_free(sra);
>  			rv = 2;
>  			goto out_unlock;
>  		}
> --
> 1.7.9.1.266.g24ee9
> --

Applied, thanks.

NeilBrown

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]