This is a note to let you know that I've just added the patch titled

    NFS: nfs_set_pgio_error sometimes misses errors

to the 4.2-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfs-nfs_set_pgio_error-sometimes-misses-errors.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From e9ae58aeee8842a50f7e199d602a5ccb2e41a95f Mon Sep 17 00:00:00 2001
From: Trond Myklebust <[email protected]>
Date: Mon, 17 Aug 2015 12:57:07 -0500
Subject: NFS: nfs_set_pgio_error sometimes misses errors

From: Trond Myklebust <[email protected]>

commit e9ae58aeee8842a50f7e199d602a5ccb2e41a95f upstream.

We should ensure that we always set the pgio_header's error field
if a READ or WRITE RPC call returns an error. The current code depends
on 'hdr->good_bytes' always being initialised to a large value, which
is not always done correctly by callers.
When this happens, applications may end up missing important errors.

Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/nfs/pagelist.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -77,8 +77,8 @@ EXPORT_SYMBOL_GPL(nfs_pgheader_init);
 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos)
 {
        spin_lock(&hdr->lock);
-       if (pos < hdr->io_start + hdr->good_bytes) {
-               set_bit(NFS_IOHDR_ERROR, &hdr->flags);
+       if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags)
+           || pos < hdr->io_start + hdr->good_bytes) {
                clear_bit(NFS_IOHDR_EOF, &hdr->flags);
                hdr->good_bytes = pos - hdr->io_start;
                hdr->error = error;


Patches currently in stable-queue which might be from 
[email protected] are

queue-4.2/nfs41-flexfiles-zero-out-ds-write-wcc.patch
queue-4.2/nfs-nfs_set_pgio_error-sometimes-misses-errors.patch
queue-4.2/nfs-fix-a-null-pointer-dereference-of-migration-recovery-ops-for-v4.2-client.patch
queue-4.2/sunrpc-xs_reset_transport-must-mark-the-connection-as-disconnected.patch
queue-4.2/nfs-fix-truncated-client-owner-id-without-proto-type.patch
queue-4.2/nfs-don-t-let-the-ctime-override-attribute-barriers.patch
queue-4.2/sunrpc-fix-a-thinko-in-xs_connect.patch
queue-4.2/nfsv4-don-t-set-setattr-for-o_rdonly-o_excl.patch
queue-4.2/nfs41-flexfiles-update-inode-after-write-finishes.patch
queue-4.2/nfsv4.1-pnfs-fix-borken-function-_same_data_server_addrs_locked.patch
queue-4.2/nfsv4-force-a-post-op-attribute-update-when-holding-a-delegation.patch
queue-4.2/nfsv4.1-pnfs-fix-atomicity-of-commit-list-updates.patch
queue-4.2/nfsv4.1-flexfiles-fix-a-protocol-error-in-layoutreturn.patch
queue-4.2/revert-nfsv4-remove-incorrect-check-in-can_open_delegated.patch
queue-4.2/nfsv4.1-fix-a-protocol-issue-with-close-stateids.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to