diff options
author | Dominique Martinet <asmadeus@codewreck.org> | 2022-11-18 16:44:41 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-12-14 13:31:54 +0300 |
commit | a8c5ffb4dffd30ae663497e1cedfcee0a1b65b71 (patch) | |
tree | 3ee08edf542656d0df83dca822388586ea886904 /net/9p | |
parent | ec36ebae3667326ab17e544aab9a634cc9d545ea (diff) | |
download | linux-a8c5ffb4dffd30ae663497e1cedfcee0a1b65b71.tar.xz |
9p/xen: check logical size for buffer size
[ Upstream commit 391c18cf776eb4569ecda1f7794f360fe0a45a26 ]
trans_xen did not check the data fits into the buffer before copying
from the xen ring, but we probably should.
Add a check that just skips the request and return an error to
userspace if it did not fit
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Link: https://lkml.kernel.org/r/20221118135542.63400-1-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/9p')
-rw-r--r-- | net/9p/trans_xen.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index 432ac5a16f2e..6c8a33f98f09 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -231,6 +231,14 @@ static void p9_xen_response(struct work_struct *work) continue; } + if (h.size > req->rc.capacity) { + dev_warn(&priv->dev->dev, + "requested packet size too big: %d for tag %d with capacity %zd\n", + h.size, h.tag, req->rc.capacity); + req->status = REQ_STATUS_ERROR; + goto recv_error; + } + memcpy(&req->rc, &h, sizeof(h)); req->rc.offset = 0; @@ -240,6 +248,7 @@ static void p9_xen_response(struct work_struct *work) masked_prod, &masked_cons, XEN_9PFS_RING_SIZE(ring)); +recv_error: virt_mb(); cons += h.size; ring->intf->in_cons = cons; |