diff options
author | Dominique Martinet <asmadeus@codewreck.org> | 2022-11-18 16:44:41 +0300 |
---|---|---|
committer | Dominique Martinet <asmadeus@codewreck.org> | 2022-11-23 08:01:27 +0300 |
commit | 391c18cf776eb4569ecda1f7794f360fe0a45a26 (patch) | |
tree | 10a3ffb03e458b1461069ff48257b6f72cfc4836 /net | |
parent | 6854fadbeee10891ed74246bdc05031906b6c8cf (diff) | |
download | linux-391c18cf776eb4569ecda1f7794f360fe0a45a26.tar.xz |
9p/xen: check logical size for buffer size
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>
Diffstat (limited to 'net')
-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 b15c64128c3e..aaa5fd364691 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -208,6 +208,14 @@ 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; @@ -217,6 +225,7 @@ 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; |