projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 677c3905 GKH |
1 | From 7dc72d5f7a0ec97a53e126c46e2cbd2560757955 Mon Sep 17 00:00:00 2001 |
| 2 | From: Trond Myklebust <trond.myklebust@primarydata.com> | |
| 3 | Date: Thu, 22 Sep 2016 13:38:52 -0400 | |
| 4 | Subject: NFS: Fix inode corruption in nfs_prime_dcache() | |
| 5 | ||
| 6 | From: Trond Myklebust <trond.myklebust@primarydata.com> | |
| 7 | ||
| 8 | commit 7dc72d5f7a0ec97a53e126c46e2cbd2560757955 upstream. | |
| 9 | ||
| 10 | Due to inode number reuse in filesystems, we can end up corrupting the | |
| 11 | inode on our client if we apply the file attributes without ensuring that | |
| 12 | the filehandle matches. | |
| 13 | Typical symptoms include spurious "mode changed" reports in the syslog. | |
| 14 | ||
| 15 | We still do want to ensure that we don't invalidate the dentry if the | |
| 16 | inode number matches, but we don't have a filehandle. | |
| 17 | ||
| 18 | Fixes: fa9233699cc1 ("NFS: Don't require a filehandle to refresh...") | |
| 19 | Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> | |
| 20 | Tested-by: Oleg Drokin <green@linuxhacker.ru> | |
| 21 | Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> | |
| 22 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 23 | ||
| 24 | --- | |
| 25 | fs/nfs/dir.c | 16 +++++++++++----- | |
| 26 | 1 file changed, 11 insertions(+), 5 deletions(-) | |
| 27 | ||
| 28 | --- a/fs/nfs/dir.c | |
| 29 | +++ b/fs/nfs/dir.c | |
| 30 | @@ -435,11 +435,11 @@ int nfs_same_file(struct dentry *dentry, | |
| 31 | return 0; | |
| 32 | ||
| 33 | nfsi = NFS_I(inode); | |
| 34 | - if (entry->fattr->fileid == nfsi->fileid) | |
| 35 | - return 1; | |
| 36 | - if (nfs_compare_fh(entry->fh, &nfsi->fh) == 0) | |
| 37 | - return 1; | |
| 38 | - return 0; | |
| 39 | + if (entry->fattr->fileid != nfsi->fileid) | |
| 40 | + return 0; | |
| 41 | + if (entry->fh->size && nfs_compare_fh(entry->fh, &nfsi->fh) != 0) | |
| 42 | + return 0; | |
| 43 | + return 1; | |
| 44 | } | |
| 45 | ||
| 46 | static | |
| 47 | @@ -517,6 +517,8 @@ again: | |
| 48 | &entry->fattr->fsid)) | |
| 49 | goto out; | |
| 50 | if (nfs_same_file(dentry, entry)) { | |
| 51 | + if (!entry->fh->size) | |
| 52 | + goto out; | |
| 53 | nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); | |
| 54 | status = nfs_refresh_inode(d_inode(dentry), entry->fattr); | |
| 55 | if (!status) | |
| 56 | @@ -529,6 +531,10 @@ again: | |
| 57 | goto again; | |
| 58 | } | |
| 59 | } | |
| 60 | + if (!entry->fh->size) { | |
| 61 | + d_lookup_done(dentry); | |
| 62 | + goto out; | |
| 63 | + } | |
| 64 | ||
| 65 | inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr, entry->label); | |
| 66 | alias = d_splice_alias(inode, dentry); |