Hi,
The Coverity checker found a memory leak in xfs_inactive().
The offending code is this bit :
1671 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
At conditional (1): "truncate != 0" taking true path
1672 if (truncate) {
1673 /*
1674 * Do the xfs_itruncate_start() call before
1675 * reserving any log space because itruncate_start
1676 * will call into the buffer cache and we can't
1677 * do that within a transaction.
1678 */
1679 xfs_ilock(ip, XFS_IOLOCK_EXCL);
1680
1681 error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0);
At conditional (2): "error != 0" taking true path
1682 if (error) {
1683 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
Event leaked_storage: Returned without freeing storage "tp"
Also see events: [alloc_fn][var_assign]
1684 return VN_INACTIVE_CACHE;
1685 }
So, the code allocates a transaction, but in the case where 'truncate' is !=0 and xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0); happens to return an error, we'll just return from the function without dealing with the memory allocated byxfs_trans_alloc() and assigned to 'tp', thus it'll be orphaned/leaked - not good.
What I'm wondering is this; is it enough, at this point, to call xfs_trans_free(tp); (it would seem to me that would be OK, but I'm not intimite with this code) or do we need a full xfs_trans_cancel(tp, 0); ???
In case I'm right and xfs_trans_free(tp); is all we need, then please consider the patch below. Otherwise please NACK the patch and I'll cook up another one :-)
Fix memory leak on error in xfs_inactive().
Signed-off-by: Jesper Juhl <[email protected]>
---
fs/xfs/xfs_vnodeops.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index de17aed..e0d3d51 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -1681,6 +1681,7 @@ xfs_inactive(
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0);
if (error) {
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+ xfs_trans_free(tp);
return VN_INACTIVE_CACHE;
}
--
Jesper Juhl <[email protected]>
Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please http://www.expita.com/nomime.html
On Wed, May 16, 2007 at 11:31:16PM +0200, Jesper Juhl wrote:
> Hi,
>
> The Coverity checker found a memory leak in xfs_inactive().
....
> So, the code allocates a transaction, but in the case where 'truncate' is
> !=0 and xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0); happens to return
> an error, we'll just return from the function without dealing with the
> memory allocated byxfs_trans_alloc() and assigned to 'tp', thus it'll be
> orphaned/leaked - not good.
Yeah, introduced by:
http://git2.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=d3cf209476b72c83907a412b6708c5e498410aa7
Thanks for reporting the problem, Jesper.
> What I'm wondering is this; is it enough, at this point, to call
> xfs_trans_free(tp); (it would seem to me that would be OK, but I'm not
> intimite with this code) or do we need a full xfs_trans_cancel(tp, 0); ???
xfs_trans_free() is not supposed to be called by anything but the transaction
code (it's static). So a xfs_trans_cancel() would need to be issued.
> In case I'm right and xfs_trans_free(tp); is all we need, then please
> consider the patch below. Otherwise please NACK the patch and I'll cook up
> another one :-)
NACK ;)
xfs_trans_cancel() is needed. Patch below.
Cheers,
Dave.
--
Dave Chinner
Principal Engineer
SGI Australian Software Group
---
fs/xfs/xfs_vnodeops.c | 1 +
1 file changed, 1 insertion(+)
Index: 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_vnodeops.c 2007-05-11 16:04:03.000000000 +1000
+++ 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c 2007-05-17 12:37:25.671399078 +1000
@@ -1710,6 +1710,7 @@ xfs_inactive(
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0);
if (error) {
+ xfs_trans_cancel(tp, 0);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return VN_INACTIVE_CACHE;
}
On Thursday 17 May 2007 04:40:24 David Chinner wrote:
> On Wed, May 16, 2007 at 11:31:16PM +0200, Jesper Juhl wrote:
> > Hi,
> >
> > The Coverity checker found a memory leak in xfs_inactive().
> ....
> > So, the code allocates a transaction, but in the case where 'truncate' is
> > !=0 and xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0); happens to return
> > an error, we'll just return from the function without dealing with the
> > memory allocated byxfs_trans_alloc() and assigned to 'tp', thus it'll be
> > orphaned/leaked - not good.
>
> Yeah, introduced by:
>
> http://git2.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=d3cf209476b72c83907a412b6708c5e498410aa7
>
> Thanks for reporting the problem, Jesper.
>
You are welcome.
That commit introduces the same problem in xfs_inactive_free_eofblocks().
Patch to fix it below.
> > What I'm wondering is this; is it enough, at this point, to call
> > xfs_trans_free(tp); (it would seem to me that would be OK, but I'm not
> > intimite with this code) or do we need a full xfs_trans_cancel(tp, 0); ???
>
> xfs_trans_free() is not supposed to be called by anything but the transaction
> code (it's static). So a xfs_trans_cancel() would need to be issued.
>
Makes sense. Thanks. I completely missed the static nature :-/
Fix XFS memory leak; allocated transaction not freed in xfs_inactive_free_eofblocks() in failure case.
Signed-off-by: Jesper Juhl <[email protected]>
---
fs/xfs/xfs_vnodeops.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index de17aed..32519cf 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -1260,6 +1260,7 @@ xfs_inactive_free_eofblocks(
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE,
ip->i_size);
if (error) {
+ xfs_trans_cancel(tp, 0);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
Any chance the patches below that fix two mem leaks in XFS will make
it in in time for 2.6.22? I believe they should...
On 18/05/07, Jesper Juhl <[email protected]> wrote:
> On Thursday 17 May 2007 04:40:24 David Chinner wrote:
> > On Wed, May 16, 2007 at 11:31:16PM +0200, Jesper Juhl wrote:
> > > Hi,
> > >
> > > The Coverity checker found a memory leak in xfs_inactive().
> > ....
> > > So, the code allocates a transaction, but in the case where 'truncate' is
> > > !=0 and xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0); happens to return
> > > an error, we'll just return from the function without dealing with the
> > > memory allocated byxfs_trans_alloc() and assigned to 'tp', thus it'll be
> > > orphaned/leaked - not good.
> >
> > Yeah, introduced by:
> >
> > http://git2.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=d3cf209476b72c83907a412b6708c5e498410aa7
> >
> > Thanks for reporting the problem, Jesper.
> >
> You are welcome.
>
> That commit introduces the same problem in xfs_inactive_free_eofblocks().
> Patch to fix it below.
>
> > > What I'm wondering is this; is it enough, at this point, to call
> > > xfs_trans_free(tp); (it would seem to me that would be OK, but I'm not
> > > intimite with this code) or do we need a full xfs_trans_cancel(tp, 0); ???
> >
> > xfs_trans_free() is not supposed to be called by anything but the transaction
> > code (it's static). So a xfs_trans_cancel() would need to be issued.
> >
> Makes sense. Thanks. I completely missed the static nature :-/
>
>
>
> Fix XFS memory leak; allocated transaction not freed in xfs_inactive_free_eofblocks() in failure case.
>
> Signed-off-by: Jesper Juhl <[email protected]>
> ---
> fs/xfs/xfs_vnodeops.c | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
> index de17aed..32519cf 100644
> --- a/fs/xfs/xfs_vnodeops.c
> +++ b/fs/xfs/xfs_vnodeops.c
> @@ -1260,6 +1260,7 @@ xfs_inactive_free_eofblocks(
> error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE,
> ip->i_size);
> if (error) {
> + xfs_trans_cancel(tp, 0);
> xfs_iunlock(ip, XFS_IOLOCK_EXCL);
> return error;
> }
>
>
--
Jesper Juhl <[email protected]>
Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please http://www.expita.com/nomime.html