6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dan Carpenter dan.carpenter@linaro.org
[ Upstream commit 39aaa337449e71a41d4813be0226a722827ba606 ]
The clean up in idxd_setup_wqs() has had a couple bugs because the error handling is a bit subtle. It's simpler to just re-write it in a cleaner way. The issues here are:
1) If "idxd->max_wqs" is <= 0 then we call put_device(conf_dev) when "conf_dev" hasn't been initialized. 2) If kzalloc_node() fails then again "conf_dev" is invalid. It's either uninitialized or it points to the "conf_dev" from the previous iteration so it leads to a double free.
It's better to free partial loop iterations within the loop and then the unwinding at the end can handle whole loop iterations. I also renamed the labels to describe what the goto does and not where the goto was located.
Fixes: 3fd2f4bc010c ("dmaengine: idxd: fix memory leak in error handling path of idxd_setup_wqs") Reported-by: Colin Ian King colin.i.king@gmail.com Closes: https://lore.kernel.org/all/20250811095836.1642093-1-colin.i.king@gmail.com/ Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Reviewed-by: Dave Jiang dave.jiang@intel.com Link: https://lore.kernel.org/r/aJnJW3iYTDDCj9sk@stanley.mountain Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma/idxd/init.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-)
diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 163a276d2670e..4b999c5802f4b 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -179,27 +179,30 @@ static int idxd_setup_wqs(struct idxd_device *idxd) idxd->wq_enable_map = bitmap_zalloc_node(idxd->max_wqs, GFP_KERNEL, dev_to_node(dev)); if (!idxd->wq_enable_map) { rc = -ENOMEM; - goto err_bitmap; + goto err_free_wqs; }
for (i = 0; i < idxd->max_wqs; i++) { wq = kzalloc_node(sizeof(*wq), GFP_KERNEL, dev_to_node(dev)); if (!wq) { rc = -ENOMEM; - goto err; + goto err_unwind; }
idxd_dev_set_type(&wq->idxd_dev, IDXD_DEV_WQ); conf_dev = wq_confdev(wq); wq->id = i; wq->idxd = idxd; - device_initialize(wq_confdev(wq)); + device_initialize(conf_dev); conf_dev->parent = idxd_confdev(idxd); conf_dev->bus = &dsa_bus_type; conf_dev->type = &idxd_wq_device_type; rc = dev_set_name(conf_dev, "wq%d.%d", idxd->id, wq->id); - if (rc < 0) - goto err; + if (rc < 0) { + put_device(conf_dev); + kfree(wq); + goto err_unwind; + }
mutex_init(&wq->wq_lock); init_waitqueue_head(&wq->err_queue); @@ -210,15 +213,20 @@ static int idxd_setup_wqs(struct idxd_device *idxd) wq->enqcmds_retries = IDXD_ENQCMDS_RETRIES; wq->wqcfg = kzalloc_node(idxd->wqcfg_size, GFP_KERNEL, dev_to_node(dev)); if (!wq->wqcfg) { + put_device(conf_dev); + kfree(wq); rc = -ENOMEM; - goto err; + goto err_unwind; }
if (idxd->hw.wq_cap.op_config) { wq->opcap_bmap = bitmap_zalloc(IDXD_MAX_OPCAP_BITS, GFP_KERNEL); if (!wq->opcap_bmap) { + kfree(wq->wqcfg); + put_device(conf_dev); + kfree(wq); rc = -ENOMEM; - goto err_opcap_bmap; + goto err_unwind; } bitmap_copy(wq->opcap_bmap, idxd->opcap_bmap, IDXD_MAX_OPCAP_BITS); } @@ -229,13 +237,7 @@ static int idxd_setup_wqs(struct idxd_device *idxd)
return 0;
-err_opcap_bmap: - kfree(wq->wqcfg); - -err: - put_device(conf_dev); - kfree(wq); - +err_unwind: while (--i >= 0) { wq = idxd->wqs[i]; if (idxd->hw.wq_cap.op_config) @@ -244,11 +246,10 @@ static int idxd_setup_wqs(struct idxd_device *idxd) conf_dev = wq_confdev(wq); put_device(conf_dev); kfree(wq); - } bitmap_free(idxd->wq_enable_map);
-err_bitmap: +err_free_wqs: kfree(idxd->wqs);
return rc;