Merge tag '9p-for-6.1-rc7' of https://github.com/martinetd/linux
Pull 9p fixes from Dominique Martinet:
- 9p now uses a variable size for its recv buffer, but every place
hadn't been updated properly to use it and some buffer overflows have
been found and needed fixing.
There's still one place where msize is incorrectly used in a safety
check (p9_check_errors), but all paths leading to it should already
be avoiding overflows and that patch took a bit more time to get
right for zero-copy requests so I'll send it for 6.2
- yet another race condition in p9_conn_cancel introduced by a fix for
a syzbot report in the same place. Maybe at some point we'll get it
right without burning it all down...
* tag '9p-for-6.1-rc7' of https://github.com/martinetd/linux:
9p/xen: check logical size for buffer size
9p/fd: Use P9_HDRSZ for header size
9p/fd: Fix write overflow in p9_read_work
9p/fd: fix issue of list_del corruption in p9_fd_cancel()
diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index 56a1867..eeea0a6 100644
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -120,7 +120,7 @@
struct list_head unsent_req_list;
struct p9_req_t *rreq;
struct p9_req_t *wreq;
- char tmp_buf[7];
+ char tmp_buf[P9_HDRSZ];
struct p9_fcall rc;
int wpos;
int wsize;
@@ -202,9 +202,11 @@
list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) {
list_move(&req->req_list, &cancel_list);
+ req->status = REQ_STATUS_ERROR;
}
list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) {
list_move(&req->req_list, &cancel_list);
+ req->status = REQ_STATUS_ERROR;
}
spin_unlock(&m->req_lock);
@@ -291,7 +293,7 @@
if (!m->rc.sdata) {
m->rc.sdata = m->tmp_buf;
m->rc.offset = 0;
- m->rc.capacity = 7; /* start by reading header */
+ m->rc.capacity = P9_HDRSZ; /* start by reading header */
}
clear_bit(Rpending, &m->wsched);
@@ -314,7 +316,7 @@
p9_debug(P9_DEBUG_TRANS, "got new header\n");
/* Header size */
- m->rc.size = 7;
+ m->rc.size = P9_HDRSZ;
err = p9_parse_header(&m->rc, &m->rc.size, NULL, NULL, 0);
if (err) {
p9_debug(P9_DEBUG_ERROR,
@@ -322,14 +324,6 @@
goto error;
}
- if (m->rc.size >= m->client->msize) {
- p9_debug(P9_DEBUG_ERROR,
- "requested packet size too big: %d\n",
- m->rc.size);
- err = -EIO;
- goto error;
- }
-
p9_debug(P9_DEBUG_TRANS,
"mux %p pkt: size: %d bytes tag: %d\n",
m, m->rc.size, m->rc.tag);
@@ -342,6 +336,14 @@
goto error;
}
+ if (m->rc.size > m->rreq->rc.capacity) {
+ p9_debug(P9_DEBUG_ERROR,
+ "requested packet size too big: %d for tag %d with capacity %zd\n",
+ m->rc.size, m->rc.tag, m->rreq->rc.capacity);
+ err = -EIO;
+ goto error;
+ }
+
if (!m->rreq->rc.sdata) {
p9_debug(P9_DEBUG_ERROR,
"No recv fcall for tag %d (req %p), disconnecting!\n",
diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
index b15c641..aaa5fd3 100644
--- a/net/9p/trans_xen.c
+++ b/net/9p/trans_xen.c
@@ -208,6 +208,14 @@
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 @@
masked_prod, &masked_cons,
XEN_9PFS_RING_SIZE(ring));
+recv_error:
virt_mb();
cons += h.size;
ring->intf->in_cons = cons;
