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 --- rust/proc-macro2/location.rs | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 rust/proc-macro2/location.rs (limited to 'rust/proc-macro2/location.rs') diff --git a/rust/proc-macro2/location.rs b/rust/proc-macro2/location.rs new file mode 100644 index 000000000..3a11871e2 --- /dev/null +++ b/rust/proc-macro2/location.rs @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +use core::cmp::Ordering; + +/// A line-column pair representing the start or end of a `Span`. +/// +/// This type is semver exempt and not exposed by default. +#[cfg_attr(docsrs, doc(cfg(feature = "span-locations")))] +#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)] +pub struct LineColumn { + /// The 1-indexed line in the source file on which the span starts or ends + /// (inclusive). + pub line: usize, + /// The 0-indexed column (in UTF-8 characters) in the source file on which + /// the span starts or ends (inclusive). + pub column: usize, +} + +impl Ord for LineColumn { + fn cmp(&self, other: &Self) -> Ordering { + self.line + .cmp(&other.line) + .then(self.column.cmp(&other.column)) + } +} + +impl PartialOrd for LineColumn { + fn partial_cmp(&self, other: &Self) -> Option { + Some(self.cmp(other)) + } +} -- cgit v1.3.1