Messages in this thread Patch in this message | | | From | Jesper Juhl <> | Subject | [RFC][PATCH] XFS: memory leak in xfs_inactive() - is xfs_trans_free() enough or do we need xfs_trans_cancel() ? | Date | Wed, 16 May 2007 23:31:16 +0200 |
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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 <jesper.juhl@gmail.com> --- 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 <jesper.juhl@gmail.com> 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
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