Commit 4bbdc8a4 authored by Toke Høiland-Jørgensen's avatar Toke Høiland-Jørgensen Committed by Liu Jian
Browse files

xdp: Allow registering memory model without rxq reference 

stable inclusion
from stable-v5.10.221
commit 5a3035306a0becc121023c5ef363bdf165f4f1ba
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAGENG
CVE: CVE-2024-42082

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5a3035306a0becc121023c5ef363bdf165f4f1ba



---------------------------

[ Upstream commit 4a48ef70 ]

The functions that register an XDP memory model take a struct xdp_rxq as
parameter, but the RXQ is not actually used for anything other than pulling
out the struct xdp_mem_info that it embeds. So refactor the register
functions and export variants that just take a pointer to the xdp_mem_info.

This is in preparation for enabling XDP_REDIRECT in bpf_prog_run(), using a
page_pool instance that is not connected to any network device.

Signed-off-by: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103150812.87914-2-toke@redhat.com


Stable-dep-of: 7e9f79428372 ("xdp: Remove WARN() from __xdp_reg_mem_model()")
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarLiu Jian <liujian56@huawei.com>
parent a4e933e8

include/net/xdp.h

+3 −0
Original line number Diff line number Diff line
@@ -224,6 +224,9 @@ bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq); 
int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,

			       enum xdp_mem_type type, void *allocator);

void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq);

int xdp_reg_mem_model(struct xdp_mem_info *mem,

		      enum xdp_mem_type type, void *allocator);

void xdp_unreg_mem_model(struct xdp_mem_info *mem);



/* Drivers not supporting XDP metadata can use this helper, which

 * rejects any room expansion for metadata as a result.

net/core/xdp.c

+62 −30
Original line number Diff line number Diff line
@@ -110,20 +110,15 @@ static void mem_allocator_disconnect(void *allocator) 
	mutex_unlock(&mem_id_lock);

}



void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq)

void xdp_unreg_mem_model(struct xdp_mem_info *mem)

{

	struct xdp_mem_allocator *xa;

	int type = xdp_rxq->mem.type;

	int id = xdp_rxq->mem.id;

	int type = mem->type;

	int id = mem->id;



	/* Reset mem info to defaults */

	xdp_rxq->mem.id = 0;

	xdp_rxq->mem.type = 0;



	if (xdp_rxq->reg_state != REG_STATE_REGISTERED) {

		WARN(1, "Missing register, driver bug");

		return;

	}

	mem->id = 0;

	mem->type = 0;



	if (id == 0)

		return;
@@ -135,6 +130,17 @@ void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq) 
		rcu_read_unlock();

	}

}

EXPORT_SYMBOL_GPL(xdp_unreg_mem_model);



void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq)

{

	if (xdp_rxq->reg_state != REG_STATE_REGISTERED) {

		WARN(1, "Missing register, driver bug");

		return;

	}



	xdp_unreg_mem_model(&xdp_rxq->mem);

}

EXPORT_SYMBOL_GPL(xdp_rxq_info_unreg_mem_model);



void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq)
@@ -260,28 +266,24 @@ static bool __is_supported_mem_type(enum xdp_mem_type type) 
	return true;

}



int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,

			       enum xdp_mem_type type, void *allocator)

static struct xdp_mem_allocator *__xdp_reg_mem_model(struct xdp_mem_info *mem,

						     enum xdp_mem_type type,

						     void *allocator)

{

	struct xdp_mem_allocator *xdp_alloc;

	gfp_t gfp = GFP_KERNEL;

	int id, errno, ret;

	void *ptr;



	if (xdp_rxq->reg_state != REG_STATE_REGISTERED) {

		WARN(1, "Missing register, driver bug");

		return -EFAULT;

	}



	if (!__is_supported_mem_type(type))

		return -EOPNOTSUPP;

		return ERR_PTR(-EOPNOTSUPP);



	xdp_rxq->mem.type = type;

	mem->type = type;



	if (!allocator) {

		if (type == MEM_TYPE_PAGE_POOL)

			return -EINVAL; /* Setup time check page_pool req */

		return 0;

			return ERR_PTR(-EINVAL); /* Setup time check page_pool req */

		return NULL;

	}



	/* Delay init of rhashtable to save memory if feature isn't used */
@@ -291,13 +293,13 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, 
		mutex_unlock(&mem_id_lock);

		if (ret < 0) {

			WARN_ON(1);

			return ret;

			return ERR_PTR(ret);

		}

	}



	xdp_alloc = kzalloc(sizeof(*xdp_alloc), gfp);

	if (!xdp_alloc)

		return -ENOMEM;

		return ERR_PTR(-ENOMEM);



	mutex_lock(&mem_id_lock);

	id = __mem_id_cyclic_get(gfp);
@@ -305,15 +307,15 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, 
		errno = id;

		goto err;

	}

	xdp_rxq->mem.id = id;

	xdp_alloc->mem  = xdp_rxq->mem;

	mem->id = id;

	xdp_alloc->mem = *mem;

	xdp_alloc->allocator = allocator;



	/* Insert allocator into ID lookup table */

	ptr = rhashtable_insert_slow(mem_id_ht, &id, &xdp_alloc->node);

	if (IS_ERR(ptr)) {

		ida_simple_remove(&mem_id_pool, xdp_rxq->mem.id);

		xdp_rxq->mem.id = 0;

		ida_simple_remove(&mem_id_pool, mem->id);

		mem->id = 0;

		errno = PTR_ERR(ptr);

		goto err;

	}
@@ -323,13 +325,43 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, 


	mutex_unlock(&mem_id_lock);



	trace_mem_connect(xdp_alloc, xdp_rxq);

	return 0;

	return xdp_alloc;

err:

	mutex_unlock(&mem_id_lock);

	kfree(xdp_alloc);

	return errno;

	return ERR_PTR(errno);

}



int xdp_reg_mem_model(struct xdp_mem_info *mem,

		      enum xdp_mem_type type, void *allocator)

{

	struct xdp_mem_allocator *xdp_alloc;



	xdp_alloc = __xdp_reg_mem_model(mem, type, allocator);

	if (IS_ERR(xdp_alloc))

		return PTR_ERR(xdp_alloc);

	return 0;

}

EXPORT_SYMBOL_GPL(xdp_reg_mem_model);



int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,

			       enum xdp_mem_type type, void *allocator)

{

	struct xdp_mem_allocator *xdp_alloc;



	if (xdp_rxq->reg_state != REG_STATE_REGISTERED) {

		WARN(1, "Missing register, driver bug");

		return -EFAULT;

	}



	xdp_alloc = __xdp_reg_mem_model(&xdp_rxq->mem, type, allocator);

	if (IS_ERR(xdp_alloc))

		return PTR_ERR(xdp_alloc);



	trace_mem_connect(xdp_alloc, xdp_rxq);

	return 0;

}



EXPORT_SYMBOL_GPL(xdp_rxq_info_reg_mem_model);



/* XDP RX runs under NAPI protection, and in different delivery error