This is a note to let you know that I've just added the patch titled
nfsd: call op_release, even when op_func returns an error
to the 5.15-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:
nfsd-call-op_release-even-when-op_func-returns-an-er.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 39831c674abd795e639cddf07c12834e115fa2df
Author: Jeff Layton <jlayton@xxxxxxxxxx>
Date: Mon Mar 27 06:21:37 2023 -0400
nfsd: call op_release, even when op_func returns an error
[ Upstream commit 15a8b55dbb1ba154d82627547c5761cac884d810 ]
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@xxxxxxxxxx>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2181403
Fixes: 34b1744c91cc ("nfsd4: define ->op_release for compound ops")
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
index 6bb23bca154a5..835ea2ed049ee 100644
--- a/fs/nfsd/blocklayout.c
+++ b/fs/nfsd/blocklayout.c
@@ -298,6 +298,7 @@ nfsd4_block_get_device_info_scsi(struct super_block *sb,
out_free_dev:
kfree(dev);
+ gdp->gd_device = NULL;
return ret;
}
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 9c9ff3bdc62a9..30c64c3f5fa05 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -5398,10 +5398,8 @@ 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;
@@ -5416,8 +5414,6 @@ 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 */
@@ -5458,6 +5454,9 @@ 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);
}
/*
