nfsd: call op_release, even when op_func returns an error

For ops with "trivial" replies, nfsd4_encode_operation will shortcut
most of the encoding work and skip to just marshalling up the status.
One of the things it skips is calling op_release. This could cause a
memory leak in the layoutget codepath if there is an error at an
inopportune time.

Have the compound processing engine always call op_release, even when
op_func sets an error in op->status. With this change, we also need
nfsd4_block_get_device_info_scsi to set the gd_device pointer to NULL
on error to avoid a double free.

Reported-by: Zhi Li <yieli@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2181403
Fixes: 34b1744c91 ("nfsd4: define ->op_release for compound ops")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit is contained in:
Jeff Layton 2023-03-27 06:21:37 -04:00 committed by Chuck Lever
parent 804d8e0a6e
commit 15a8b55dbb
2 changed files with 6 additions and 6 deletions

View File

@ -297,6 +297,7 @@ nfsd4_block_get_device_info_scsi(struct super_block *sb,
out_free_dev:
kfree(dev);
gdp->gd_device = NULL;
return ret;
}

View File

@ -5400,10 +5400,8 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
__be32 *p;
p = xdr_reserve_space(xdr, 8);
if (!p) {
WARN_ON_ONCE(1);
return;
}
if (!p)
goto release;
*p++ = cpu_to_be32(op->opnum);
post_err_offset = xdr->buf->len;
@ -5418,8 +5416,6 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
op->status = encoder(resp, op->status, &op->u);
if (op->status)
trace_nfsd_compound_encode_err(rqstp, op->opnum, op->status);
if (opdesc && opdesc->op_release)
opdesc->op_release(&op->u);
xdr_commit_encode(xdr);
/* nfsd4_check_resp_size guarantees enough room for error status */
@ -5460,6 +5456,9 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
}
status:
*p = op->status;
release:
if (opdesc && opdesc->op_release)
opdesc->op_release(&op->u);
}
/*