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| author | Chuck Lever <chuck.lever@oracle.com> | 2022-01-31 21:01:53 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-16 14:56:06 +0300 |
| commit | 8e0ecaf7a7e57b30284d6b3289cc436100fadc48 (patch) | |
| tree | 9ae2544ffb244f11017726ef298e2c4ce959c8a5 /fs/nfsd | |
| parent | 37f2d2cd8eadddbbd9c7bda327a9393399b2f89b (diff) | |
| download | linux-8e0ecaf7a7e57b30284d6b3289cc436100fadc48.tar.xz | |
NFSD: Fix ia_size underflow
commit e6faac3f58c7c4176b66f63def17a34232a17b0e upstream.
iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and
NFSv4 both define file size as an unsigned 64-bit type. Thus there
is a range of valid file size values an NFS client can send that is
already larger than Linux can handle.
Currently decode_fattr4() dumps a full u64 value into ia_size. If
that value happens to be larger than S64_MAX, then ia_size
underflows. I'm about to fix up the NFSv3 behavior as well, so let's
catch the underflow in the common code path: nfsd_setattr().
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/nfsd')
| -rw-r--r-- | fs/nfsd/vfs.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 738d564ca4ce..78df03843412 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -433,6 +433,10 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, .ia_size = iap->ia_size, }; + host_err = -EFBIG; + if (iap->ia_size < 0) + goto out_unlock; + host_err = notify_change(&init_user_ns, dentry, &size_attr, NULL); if (host_err) goto out_unlock; |