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 --- scripts/prune-kernel | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100755 scripts/prune-kernel (limited to 'scripts/prune-kernel') diff --git a/scripts/prune-kernel b/scripts/prune-kernel new file mode 100755 index 000000000..dadfd0e47 --- /dev/null +++ b/scripts/prune-kernel @@ -0,0 +1,25 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# because I use CONFIG_LOCALVERSION_AUTO, not the same version again and +# again, /boot and /lib/modules/ eventually fill up. +# Dumb script to purge that stuff: + +for f in "$@" +do + if rpm -qf "/lib/modules/$f" >/dev/null; then + echo "keeping $f (installed from rpm)" + elif [ $(uname -r) = "$f" ]; then + echo "keeping $f (running kernel) " + else + echo "removing $f" + rm -f "/boot/initramfs-$f.img" "/boot/System.map-$f" + rm -f "/boot/vmlinuz-$f" "/boot/config-$f" + rm -rf "/lib/modules/$f" + if [ -x "$(command -v new-kernel-pkg)" ]; then + new-kernel-pkg --remove $f + elif [ -x "$(command -v kernel-install)" ]; then + kernel-install remove $f + fi + fi +done -- cgit v1.3.1