Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 620 insertions, 0 deletions

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
new file mode 100644
index 000000000..db394f101
--- /dev/null
+++ b/fs/afs/cmservice.c
@@ -0,0 +1,620 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* AFS Cache Manager Service
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/ip.h>
+#include "internal.h"
+#include "afs_cm.h"
+#include "protocol_yfs.h"
+#define RXRPC_TRACE_ONLY_DEFINE_ENUMS
+#include <trace/events/rxrpc.h>
+
+static int afs_deliver_cb_init_call_back_state(struct afs_call *);
+static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
+static int afs_deliver_cb_probe(struct afs_call *);
+static int afs_deliver_cb_callback(struct afs_call *);
+static int afs_deliver_cb_probe_uuid(struct afs_call *);
+static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
+static void afs_cm_destructor(struct afs_call *);
+static void SRXAFSCB_CallBack(struct work_struct *);
+static void SRXAFSCB_InitCallBackState(struct work_struct *);
+static void SRXAFSCB_Probe(struct work_struct *);
+static void SRXAFSCB_ProbeUuid(struct work_struct *);
+static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
+
+static int afs_deliver_yfs_cb_callback(struct afs_call *);
+
+/*
+ * CB.CallBack operation type
+ */
+static const struct afs_call_type afs_SRXCBCallBack = {
+	.name		= "CB.CallBack",
+	.deliver	= afs_deliver_cb_callback,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_CallBack,
+};
+
+/*
+ * CB.InitCallBackState operation type
+ */
+static const struct afs_call_type afs_SRXCBInitCallBackState = {
+	.name		= "CB.InitCallBackState",
+	.deliver	= afs_deliver_cb_init_call_back_state,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_InitCallBackState,
+};
+
+/*
+ * CB.InitCallBackState3 operation type
+ */
+static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
+	.name		= "CB.InitCallBackState3",
+	.deliver	= afs_deliver_cb_init_call_back_state3,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_InitCallBackState,
+};
+
+/*
+ * CB.Probe operation type
+ */
+static const struct afs_call_type afs_SRXCBProbe = {
+	.name		= "CB.Probe",
+	.deliver	= afs_deliver_cb_probe,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_Probe,
+};
+
+/*
+ * CB.ProbeUuid operation type
+ */
+static const struct afs_call_type afs_SRXCBProbeUuid = {
+	.name		= "CB.ProbeUuid",
+	.deliver	= afs_deliver_cb_probe_uuid,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_ProbeUuid,
+};
+
+/*
+ * CB.TellMeAboutYourself operation type
+ */
+static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
+	.name		= "CB.TellMeAboutYourself",
+	.deliver	= afs_deliver_cb_tell_me_about_yourself,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_TellMeAboutYourself,
+};
+
+/*
+ * YFS CB.CallBack operation type
+ */
+static const struct afs_call_type afs_SRXYFSCB_CallBack = {
+	.name		= "YFSCB.CallBack",
+	.deliver	= afs_deliver_yfs_cb_callback,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_CallBack,
+};
+
+/*
+ * route an incoming cache manager call
+ * - return T if supported, F if not
+ */
+bool afs_cm_incoming_call(struct afs_call *call)
+{
+	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
+
+	switch (call->operation_ID) {
+	case CBCallBack:
+		call->type = &afs_SRXCBCallBack;
+		return true;
+	case CBInitCallBackState:
+		call->type = &afs_SRXCBInitCallBackState;
+		return true;
+	case CBInitCallBackState3:
+		call->type = &afs_SRXCBInitCallBackState3;
+		return true;
+	case CBProbe:
+		call->type = &afs_SRXCBProbe;
+		return true;
+	case CBProbeUuid:
+		call->type = &afs_SRXCBProbeUuid;
+		return true;
+	case CBTellMeAboutYourself:
+		call->type = &afs_SRXCBTellMeAboutYourself;
+		return true;
+	case YFSCBCallBack:
+		if (call->service_id != YFS_CM_SERVICE)
+			return false;
+		call->type = &afs_SRXYFSCB_CallBack;
+		return true;
+	default:
+		return false;
+	}
+}
+
+/*
+ * Clean up a cache manager call.
+ */
+static void afs_cm_destructor(struct afs_call *call)
+{
+	kfree(call->buffer);
+	call->buffer = NULL;
+}
+
+/*
+ * Abort a service call from within an action function.
+ */
+static void afs_abort_service_call(struct afs_call *call, u32 abort_code, int error,
+				   enum rxrpc_abort_reason why)
+{
+	rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
+				abort_code, error, why);
+	afs_set_call_complete(call, error, 0);
+}
+
+/*
+ * The server supplied a list of callbacks that it wanted to break.
+ */
+static void SRXAFSCB_CallBack(struct work_struct *work)
+{
+	struct afs_call *call = container_of(work, struct afs_call, work);
+
+	_enter("");
+
+	/* We need to break the callbacks before sending the reply as the
+	 * server holds up change visibility till it receives our reply so as
+	 * to maintain cache coherency.
+	 */
+	if (call->server) {
+		trace_afs_server(call->server->debug_id,
+				 refcount_read(&call->server->ref),
+				 atomic_read(&call->server->active),
+				 afs_server_trace_callback);
+		afs_break_callbacks(call->server, call->count, call->request);
+	}
+
+	afs_send_empty_reply(call);
+	afs_put_call(call);
+	_leave("");
+}
+
+/*
+ * deliver request data to a CB.CallBack call
+ */
+static int afs_deliver_cb_callback(struct afs_call *call)
+{
+	struct afs_callback_break *cb;
+	__be32 *bp;
+	int ret, loop;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+
+		/* extract the FID array and its count in two steps */
+		fallthrough;
+	case 1:
+		_debug("extract FID count");
+		ret = afs_extract_data(call, true);
+		if (ret < 0)
+			return ret;
+
+		call->count = ntohl(call->tmp);
+		_debug("FID count: %u", call->count);
+		if (call->count > AFSCBMAX)
+			return afs_protocol_error(call, afs_eproto_cb_fid_count);
+
+		call->buffer = kmalloc(array3_size(call->count, 3, 4),
+				       GFP_KERNEL);
+		if (!call->buffer)
+			return -ENOMEM;
+		afs_extract_to_buf(call, call->count * 3 * 4);
+		call->unmarshall++;
+
+		fallthrough;
+	case 2:
+		_debug("extract FID array");
+		ret = afs_extract_data(call, true);
+		if (ret < 0)
+			return ret;
+
+		_debug("unmarshall FID array");
+		call->request = kzalloc_objs(struct afs_callback_break,
+					     call->count);
+		if (!call->request)
+			return -ENOMEM;
+
+		cb = call->request;
+		bp = call->buffer;
+		for (loop = call->count; loop > 0; loop--, cb++) {
+			cb->fid.vid	= ntohl(*bp++);
+			cb->fid.vnode	= ntohl(*bp++);
+			cb->fid.unique	= ntohl(*bp++);
+		}
+
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+
+		/* extract the callback array and its count in two steps */
+		fallthrough;
+	case 3:
+		_debug("extract CB count");
+		ret = afs_extract_data(call, true);
+		if (ret < 0)
+			return ret;
+
+		call->count2 = ntohl(call->tmp);
+		_debug("CB count: %u", call->count2);
+		if (call->count2 != call->count && call->count2 != 0)
+			return afs_protocol_error(call, afs_eproto_cb_count);
+		call->iter = &call->def_iter;
+		iov_iter_discard(&call->def_iter, ITER_DEST, call->count2 * 3 * 4);
+		call->unmarshall++;
+
+		fallthrough;
+	case 4:
+		_debug("extract discard %zu/%u",
+		       iov_iter_count(call->iter), call->count2 * 3 * 4);
+
+		ret = afs_extract_data(call, false);
+		if (ret < 0)
+			return ret;
+
+		call->unmarshall++;
+		fallthrough;
+
+	case 5:
+		break;
+	}
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+	return 0;
+}
+
+/*
+ * allow the fileserver to request callback state (re-)initialisation
+ */
+static void SRXAFSCB_InitCallBackState(struct work_struct *work)
+{
+	struct afs_call *call = container_of(work, struct afs_call, work);
+
+	_enter("{%p}", call->server);
+
+	if (call->server)
+		afs_init_callback_state(call->server);
+	afs_send_empty_reply(call);
+	afs_put_call(call);
+	_leave("");
+}
+
+/*
+ * deliver request data to a CB.InitCallBackState call
+ */
+static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
+{
+	_enter("");
+
+	afs_extract_discard(call, 0);
+	return afs_extract_data(call, false);
+}
+
+/*
+ * deliver request data to a CB.InitCallBackState3 call
+ */
+static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
+{
+	struct afs_uuid *r;
+	unsigned loop;
+	__be32 *b;
+	int ret;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
+		if (!call->buffer)
+			return -ENOMEM;
+		afs_extract_to_buf(call, 11 * sizeof(__be32));
+		call->unmarshall++;
+
+		fallthrough;
+	case 1:
+		_debug("extract UUID");
+		ret = afs_extract_data(call, false);
+		switch (ret) {
+		case 0:		break;
+		default:	return ret;
+		}
+
+		_debug("unmarshall UUID");
+		call->request = kmalloc_obj(struct afs_uuid);
+		if (!call->request)
+			return -ENOMEM;
+
+		b = call->buffer;
+		r = call->request;
+		r->time_low			= b[0];
+		r->time_mid			= htons(ntohl(b[1]));
+		r->time_hi_and_version		= htons(ntohl(b[2]));
+		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
+		r->clock_seq_low		= ntohl(b[4]);
+
+		for (loop = 0; loop < 6; loop++)
+			r->node[loop] = ntohl(b[loop + 5]);
+
+		call->unmarshall++;
+		fallthrough;
+
+	case 2:
+		break;
+	}
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+
+	if (!call->server) {
+		trace_afs_cm_no_server_u(call, call->request);
+		return 0;
+	}
+
+	if (memcmp(call->request, &call->server->_uuid, sizeof(call->server->_uuid)) != 0) {
+		pr_notice("Callback UUID does not match fileserver UUID\n");
+		trace_afs_cm_no_server_u(call, call->request);
+		return 0;
+	}
+
+	return 0;
+}
+
+/*
+ * allow the fileserver to see if the cache manager is still alive
+ */
+static void SRXAFSCB_Probe(struct work_struct *work)
+{
+	struct afs_call *call = container_of(work, struct afs_call, work);
+
+	_enter("");
+	afs_send_empty_reply(call);
+	afs_put_call(call);
+	_leave("");
+}
+
+/*
+ * deliver request data to a CB.Probe call
+ */
+static int afs_deliver_cb_probe(struct afs_call *call)
+{
+	int ret;
+
+	_enter("");
+
+	afs_extract_discard(call, 0);
+	ret = afs_extract_data(call, false);
+	if (ret < 0)
+		return ret;
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+	return 0;
+}
+
+/*
+ * Allow the fileserver to quickly find out if the cache manager has been
+ * rebooted.
+ */
+static void SRXAFSCB_ProbeUuid(struct work_struct *work)
+{
+	struct afs_call *call = container_of(work, struct afs_call, work);
+	struct afs_uuid *r = call->request;
+
+	_enter("");
+
+	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
+		afs_send_empty_reply(call);
+	else
+		afs_abort_service_call(call, 1, 1, afs_abort_probeuuid_negative);
+
+	afs_put_call(call);
+	_leave("");
+}
+
+/*
+ * deliver request data to a CB.ProbeUuid call
+ */
+static int afs_deliver_cb_probe_uuid(struct afs_call *call)
+{
+	struct afs_uuid *r;
+	unsigned loop;
+	__be32 *b;
+	int ret;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
+		if (!call->buffer)
+			return -ENOMEM;
+		afs_extract_to_buf(call, 11 * sizeof(__be32));
+		call->unmarshall++;
+
+		fallthrough;
+	case 1:
+		_debug("extract UUID");
+		ret = afs_extract_data(call, false);
+		switch (ret) {
+		case 0:		break;
+		default:	return ret;
+		}
+
+		_debug("unmarshall UUID");
+		call->request = kmalloc_obj(struct afs_uuid);
+		if (!call->request)
+			return -ENOMEM;
+
+		b = call->buffer;
+		r = call->request;
+		r->time_low			= b[0];
+		r->time_mid			= htons(ntohl(b[1]));
+		r->time_hi_and_version		= htons(ntohl(b[2]));
+		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
+		r->clock_seq_low		= ntohl(b[4]);
+
+		for (loop = 0; loop < 6; loop++)
+			r->node[loop] = ntohl(b[loop + 5]);
+
+		call->unmarshall++;
+		fallthrough;
+
+	case 2:
+		break;
+	}
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+	return 0;
+}
+
+/*
+ * allow the fileserver to ask about the cache manager's capabilities
+ */
+static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
+{
+	struct afs_call *call = container_of(work, struct afs_call, work);
+	int loop;
+
+	struct {
+		struct /* InterfaceAddr */ {
+			__be32 nifs;
+			__be32 uuid[11];
+			__be32 ifaddr[32];
+			__be32 netmask[32];
+			__be32 mtu[32];
+		} ia;
+		struct /* Capabilities */ {
+			__be32 capcount;
+			__be32 caps[1];
+		} cap;
+	} reply;
+
+	_enter("");
+
+	memset(&reply, 0, sizeof(reply));
+
+	reply.ia.uuid[0] = call->net->uuid.time_low;
+	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
+	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
+	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
+	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
+	for (loop = 0; loop < 6; loop++)
+		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
+
+	reply.cap.capcount = htonl(1);
+	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
+	afs_send_simple_reply(call, &reply, sizeof(reply));
+	afs_put_call(call);
+	_leave("");
+}
+
+/*
+ * deliver request data to a CB.TellMeAboutYourself call
+ */
+static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
+{
+	int ret;
+
+	_enter("");
+
+	afs_extract_discard(call, 0);
+	ret = afs_extract_data(call, false);
+	if (ret < 0)
+		return ret;
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+	return 0;
+}
+
+/*
+ * deliver request data to a YFS CB.CallBack call
+ */
+static int afs_deliver_yfs_cb_callback(struct afs_call *call)
+{
+	struct afs_callback_break *cb;
+	struct yfs_xdr_YFSFid *bp;
+	size_t size;
+	int ret, loop;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+
+		/* extract the FID array and its count in two steps */
+		fallthrough;
+	case 1:
+		_debug("extract FID count");
+		ret = afs_extract_data(call, true);
+		if (ret < 0)
+			return ret;
+
+		call->count = ntohl(call->tmp);
+		_debug("FID count: %u", call->count);
+		if (call->count > YFSCBMAX)
+			return afs_protocol_error(call, afs_eproto_cb_fid_count);
+
+		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
+		call->buffer = kmalloc(size, GFP_KERNEL);
+		if (!call->buffer)
+			return -ENOMEM;
+		afs_extract_to_buf(call, size);
+		call->unmarshall++;
+
+		fallthrough;
+	case 2:
+		_debug("extract FID array");
+		ret = afs_extract_data(call, false);
+		if (ret < 0)
+			return ret;
+
+		_debug("unmarshall FID array");
+		call->request = kzalloc_objs(struct afs_callback_break,
+					     call->count);
+		if (!call->request)
+			return -ENOMEM;
+
+		cb = call->request;
+		bp = call->buffer;
+		for (loop = call->count; loop > 0; loop--, cb++) {
+			cb->fid.vid	= xdr_to_u64(bp->volume);
+			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
+			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
+			cb->fid.unique	= ntohl(bp->vnode.unique);
+			bp++;
+		}
+
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+		fallthrough;
+
+	case 3:
+		break;
+	}
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+	return 0;
+}