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authorChuck Lever <chuck.lever@oracle.com>2011-01-21 15:54:57 +0000
committerTrond Myklebust <Trond.Myklebust@netapp.com>2011-01-25 15:24:47 -0500
commit839f7ad6932d95f4d5ae7267b95c574714ff3d5b (patch)
tree63dc2eec84a5ecb846145fd1dd70fe7cdd46fa7c /fs/nfs
parentad3d2eedf0ed3611f5f86b9e4d0d15cc76c63465 (diff)
downloadlinux-839f7ad6932d95f4d5ae7267b95c574714ff3d5b.tar.bz2
NFS: Fix "kernel BUG at fs/aio.c:554!"
Nick Piggin reports: > I'm getting use after frees in aio code in NFS > > [ 2703.396766] Call Trace: > [ 2703.396858] [<ffffffff8100b057>] ? native_sched_clock+0x27/0x80 > [ 2703.396959] [<ffffffff8108509e>] ? put_lock_stats+0xe/0x40 > [ 2703.397058] [<ffffffff81088348>] ? lock_release_holdtime+0xa8/0x140 > [ 2703.397159] [<ffffffff8108a2a5>] lock_acquire+0x95/0x1b0 > [ 2703.397260] [<ffffffff811627db>] ? aio_put_req+0x2b/0x60 > [ 2703.397361] [<ffffffff81039701>] ? get_parent_ip+0x11/0x50 > [ 2703.397464] [<ffffffff81612a31>] _raw_spin_lock_irq+0x41/0x80 > [ 2703.397564] [<ffffffff811627db>] ? aio_put_req+0x2b/0x60 > [ 2703.397662] [<ffffffff811627db>] aio_put_req+0x2b/0x60 > [ 2703.397761] [<ffffffff811647fe>] do_io_submit+0x2be/0x7c0 > [ 2703.397895] [<ffffffff81164d0b>] sys_io_submit+0xb/0x10 > [ 2703.397995] [<ffffffff8100307b>] system_call_fastpath+0x16/0x1b > > Adding some tracing, it is due to nfs completing the request then > returning something other than -EIOCBQUEUED, so aio.c > also completes the request. To address this, prevent the NFS direct I/O engine from completing async iocbs when the forward path returns an error without starting any I/O. This fix appears to survive ^C during both "xfstest no. 208" and "fsx -Z." It's likely this bug has existed for a very long while, as we are seeing very similar symptoms in OEL 5. Copying stable. Cc: Stable <stable@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs')
-rw-r--r--fs/nfs/direct.c34
1 files changed, 20 insertions, 14 deletions
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index e6ace0d93c71..9943a75bb6d1 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -407,15 +407,18 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
pos += vec->iov_len;
}
+ /*
+ * If no bytes were started, return the error, and let the
+ * generic layer handle the completion.
+ */
+ if (requested_bytes == 0) {
+ nfs_direct_req_release(dreq);
+ return result < 0 ? result : -EIO;
+ }
+
if (put_dreq(dreq))
nfs_direct_complete(dreq);
-
- if (requested_bytes != 0)
- return 0;
-
- if (result < 0)
- return result;
- return -EIO;
+ return 0;
}
static ssize_t nfs_direct_read(struct kiocb *iocb, const struct iovec *iov,
@@ -841,15 +844,18 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
pos += vec->iov_len;
}
+ /*
+ * If no bytes were started, return the error, and let the
+ * generic layer handle the completion.
+ */
+ if (requested_bytes == 0) {
+ nfs_direct_req_release(dreq);
+ return result < 0 ? result : -EIO;
+ }
+
if (put_dreq(dreq))
nfs_direct_write_complete(dreq, dreq->inode);
-
- if (requested_bytes != 0)
- return 0;
-
- if (result < 0)
- return result;
- return -EIO;
+ return 0;
}
static ssize_t nfs_direct_write(struct kiocb *iocb, const struct iovec *iov,