openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

NFS/pnfs: Fix a credential use-after-free issue in pnfs_roc() 

If the credential returned by pnfs_prepare_layoutreturn()
does not match the credential of the RPC call, then we do
end up calling pnfs_send_layoutreturn() with that credential,
so don't free it!

Fixes: 44ea8dfce0 ("NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2020-04-19 23:53:52 -04:00
parent 7bcc10585b
commit 4d8948c733
1 changed files with 2 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
fs/nfs/pnfs.c
View File

@ -1458,18 +1458,15 @@ bool pnfs_roc(struct inode *ino,
/* lo ref dropped in pnfs_roc_release() */
layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode);
/* If the creds don't match, we can't compound the layoutreturn */
if (!layoutreturn)
if (!layoutreturn || cred_fscmp(cred, lc_cred) != 0)
goto out_noroc;
if (cred_fscmp(cred, lc_cred) != 0)
goto out_noroc_put_cred;
roc = layoutreturn;
pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
res->lrs_present = 0;
layoutreturn = false;
out_noroc_put_cred:
put_cred(lc_cred);
out_noroc:
spin_unlock(&ino->i_lock);
rcu_read_unlock();