[PATCH v2] RDMA/restrack: Fix potential invalid address access

From: Wenchao Hao
Date: Mon Mar 18 2024 - 05:42:36 EST


struct rdma_restrack_entry's kern_name was set to KBUILD_MODNAME
in ib_create_cq(), while if the module exited but forgot del this
rdma_restrack_entry, it would cause a invalid address access in
rdma_restrack_clean() when print the owner of this rdma_restrack_entry.

These code is used to help find one forgotten PD release in one of the
ULPs. But it is not needed anymore, so delete them.

Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
---
drivers/infiniband/core/restrack.c | 51 +-----------------------------
1 file changed, 1 insertion(+), 50 deletions(-)

diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c
index 01a499a8b88d..438ed3588175 100644
--- a/drivers/infiniband/core/restrack.c
+++ b/drivers/infiniband/core/restrack.c
@@ -37,22 +37,6 @@ int rdma_restrack_init(struct ib_device *dev)
return 0;
}

-static const char *type2str(enum rdma_restrack_type type)
-{
- static const char * const names[RDMA_RESTRACK_MAX] = {
- [RDMA_RESTRACK_PD] = "PD",
- [RDMA_RESTRACK_CQ] = "CQ",
- [RDMA_RESTRACK_QP] = "QP",
- [RDMA_RESTRACK_CM_ID] = "CM_ID",
- [RDMA_RESTRACK_MR] = "MR",
- [RDMA_RESTRACK_CTX] = "CTX",
- [RDMA_RESTRACK_COUNTER] = "COUNTER",
- [RDMA_RESTRACK_SRQ] = "SRQ",
- };
-
- return names[type];
-};
-
/**
* rdma_restrack_clean() - clean resource tracking
* @dev: IB device
@@ -60,47 +44,14 @@ static const char *type2str(enum rdma_restrack_type type)
void rdma_restrack_clean(struct ib_device *dev)
{
struct rdma_restrack_root *rt = dev->res;
- struct rdma_restrack_entry *e;
- char buf[TASK_COMM_LEN];
- bool found = false;
- const char *owner;
int i;

for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) {
struct xarray *xa = &dev->res[i].xa;

- if (!xa_empty(xa)) {
- unsigned long index;
-
- if (!found) {
- pr_err("restrack: %s", CUT_HERE);
- dev_err(&dev->dev, "BUG: RESTRACK detected leak of resources\n");
- }
- xa_for_each(xa, index, e) {
- if (rdma_is_kernel_res(e)) {
- owner = e->kern_name;
- } else {
- /*
- * There is no need to call get_task_struct here,
- * because we can be here only if there are more
- * get_task_struct() call than put_task_struct().
- */
- get_task_comm(buf, e->task);
- owner = buf;
- }
-
- pr_err("restrack: %s %s object allocated by %s is not freed\n",
- rdma_is_kernel_res(e) ? "Kernel" :
- "User",
- type2str(e->type), owner);
- }
- found = true;
- }
+ WARN_ON(!xa_empty(xa));
xa_destroy(xa);
}
- if (found)
- pr_err("restrack: %s", CUT_HERE);
-
kfree(rt);
}

--
2.32.0