[PATCH] v9fs: fix handling of malformed 9P messages

This patch attempts to do a better job of cleaning up after detecting errors
on the transport.  This should also improve error reporting on broken
connections to servers.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Eric Van Hensbergen 2005-09-09 13:04:28 -07:00 committed by Linus Torvalds
parent b501611a6f
commit cb2e87a65d
4 changed files with 46 additions and 21 deletions

View File

@ -47,6 +47,7 @@ static struct errormap errmap[] = {
{"Operation not permitted", EPERM}, {"Operation not permitted", EPERM},
{"wstat prohibited", EPERM}, {"wstat prohibited", EPERM},
{"No such file or directory", ENOENT}, {"No such file or directory", ENOENT},
{"directory entry not found", ENOENT},
{"file not found", ENOENT}, {"file not found", ENOENT},
{"Interrupted system call", EINTR}, {"Interrupted system call", EINTR},
{"Input/output error", EIO}, {"Input/output error", EIO},

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@ -162,18 +162,21 @@ static int v9fs_recv(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
dprintk(DEBUG_MUX, "waiting for response: %d\n", req->tcall->tag); dprintk(DEBUG_MUX, "waiting for response: %d\n", req->tcall->tag);
ret = wait_event_interruptible(v9ses->read_wait, ret = wait_event_interruptible(v9ses->read_wait,
((v9ses->transport->status != Connected) || ((v9ses->transport->status != Connected) ||
(req->rcall != 0) || dprintcond(v9ses, req))); (req->rcall != 0) || (req->err < 0) ||
dprintcond(v9ses, req)));
dprintk(DEBUG_MUX, "got it: rcall %p\n", req->rcall); dprintk(DEBUG_MUX, "got it: rcall %p\n", req->rcall);
spin_lock(&v9ses->muxlock);
list_del(&req->next);
spin_unlock(&v9ses->muxlock);
if (req->err < 0)
return req->err;
if (v9ses->transport->status == Disconnected) if (v9ses->transport->status == Disconnected)
return -ECONNRESET; return -ECONNRESET;
if (ret == 0) {
spin_lock(&v9ses->muxlock);
list_del(&req->next);
spin_unlock(&v9ses->muxlock);
}
return ret; return ret;
} }
@ -245,6 +248,9 @@ v9fs_mux_rpc(struct v9fs_session_info *v9ses, struct v9fs_fcall *tcall,
if (!v9ses) if (!v9ses)
return -EINVAL; return -EINVAL;
if (!v9ses->transport || v9ses->transport->status != Connected)
return -EIO;
if (rcall) if (rcall)
*rcall = NULL; *rcall = NULL;
@ -257,6 +263,7 @@ v9fs_mux_rpc(struct v9fs_session_info *v9ses, struct v9fs_fcall *tcall,
tcall->tag = tid; tcall->tag = tid;
req.tcall = tcall; req.tcall = tcall;
req.err = 0;
req.rcall = NULL; req.rcall = NULL;
ret = v9fs_send(v9ses, &req); ret = v9fs_send(v9ses, &req);
@ -371,16 +378,21 @@ static int v9fs_recvproc(void *data)
} }
err = read_message(v9ses, rcall, v9ses->maxdata + V9FS_IOHDRSZ); err = read_message(v9ses, rcall, v9ses->maxdata + V9FS_IOHDRSZ);
if (err < 0) {
kfree(rcall);
break;
}
spin_lock(&v9ses->muxlock); spin_lock(&v9ses->muxlock);
list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) { if (err < 0) {
if (rreq->tcall->tag == rcall->tag) { list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
req = rreq; rreq->err = err;
req->rcall = rcall; }
break; if(err != -ERESTARTSYS)
eprintk(KERN_ERR,
"Transport error while reading message %d\n", err);
} else {
list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
if (rreq->tcall->tag == rcall->tag) {
req = rreq;
req->rcall = rcall;
break;
}
} }
} }
@ -399,9 +411,10 @@ static int v9fs_recvproc(void *data)
spin_unlock(&v9ses->muxlock); spin_unlock(&v9ses->muxlock);
if (!req) { if (!req) {
dprintk(DEBUG_ERROR, if (err >= 0)
"unexpected response: id %d tag %d\n", dprintk(DEBUG_ERROR,
rcall->id, rcall->tag); "unexpected response: id %d tag %d\n",
rcall->id, rcall->tag);
kfree(rcall); kfree(rcall);
} }
@ -410,6 +423,8 @@ static int v9fs_recvproc(void *data)
set_current_state(TASK_INTERRUPTIBLE); set_current_state(TASK_INTERRUPTIBLE);
} }
v9ses->transport->close(v9ses->transport);
/* Inform all pending processes about the failure */ /* Inform all pending processes about the failure */
wake_up_all(&v9ses->read_wait); wake_up_all(&v9ses->read_wait);

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@ -28,6 +28,7 @@
struct v9fs_rpcreq { struct v9fs_rpcreq {
struct v9fs_fcall *tcall; struct v9fs_fcall *tcall;
struct v9fs_fcall *rcall; struct v9fs_fcall *rcall;
int err; /* error code if response failed */
/* XXX - could we put scatter/gather buffers here? */ /* XXX - could we put scatter/gather buffers here? */

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@ -254,7 +254,12 @@ v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
static void v9fs_sock_close(struct v9fs_transport *trans) static void v9fs_sock_close(struct v9fs_transport *trans)
{ {
struct v9fs_trans_sock *ts = trans ? trans->priv : NULL; struct v9fs_trans_sock *ts;
if (!trans)
return;
ts = trans->priv;
if ((ts) && (ts->s)) { if ((ts) && (ts->s)) {
dprintk(DEBUG_TRANS, "closing the socket %p\n", ts->s); dprintk(DEBUG_TRANS, "closing the socket %p\n", ts->s);
@ -264,7 +269,10 @@ static void v9fs_sock_close(struct v9fs_transport *trans)
dprintk(DEBUG_TRANS, "socket closed\n"); dprintk(DEBUG_TRANS, "socket closed\n");
} }
kfree(ts); if (ts)
kfree(ts);
trans->priv = NULL;
} }
struct v9fs_transport v9fs_trans_tcp = { struct v9fs_transport v9fs_trans_tcp = {