From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- net/wireless/ethtool.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 net/wireless/ethtool.c (limited to 'net/wireless/ethtool.c') diff --git a/net/wireless/ethtool.c b/net/wireless/ethtool.c new file mode 100644 index 000000000..46e4317cb --- /dev/null +++ b/net/wireless/ethtool.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include "core.h" +#include "rdev-ops.h" + +void cfg80211_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) +{ + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct device *pdev = wiphy_dev(wdev->wiphy); + + if (pdev->driver) + strscpy(info->driver, pdev->driver->name, + sizeof(info->driver)); + else + strscpy(info->driver, "N/A", sizeof(info->driver)); + + strscpy(info->version, init_utsname()->release, sizeof(info->version)); + + if (wdev->wiphy->fw_version[0]) + strscpy(info->fw_version, wdev->wiphy->fw_version, + sizeof(info->fw_version)); + else + strscpy(info->fw_version, "N/A", sizeof(info->fw_version)); + + strscpy(info->bus_info, dev_name(pdev), + sizeof(info->bus_info)); +} +EXPORT_SYMBOL(cfg80211_get_drvinfo); -- cgit v1.3.1