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 --- tools/testing/selftests/clock-helpers.h | 76 +++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 tools/testing/selftests/clock-helpers.h (limited to 'tools/testing/selftests/clock-helpers.h') diff --git a/tools/testing/selftests/clock-helpers.h b/tools/testing/selftests/clock-helpers.h new file mode 100644 index 000000000..01451f538 --- /dev/null +++ b/tools/testing/selftests/clock-helpers.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __CLOCK_HELPERS_H +#define __CLOCK_HELPERS_H + +#include +#include + +#define MSEC_PER_SEC 1000LL +#define USEC_PER_MSEC 1000LL +#define NSEC_PER_USEC 1000LL +#define NSEC_PER_MSEC 1000000LL +#define USEC_PER_SEC 1000000LL +#define NSEC_PER_SEC 1000000000LL +#define PSEC_PER_SEC 1000000000000LL +#define FSEC_PER_SEC 1000000000000000LL + +#ifndef CLOCK_AUX +#define CLOCK_AUX 16 +#endif + +#ifndef MAX_AUX_CLOCKS +#define MAX_AUX_CLOCKS 8 +#endif + +#ifndef CLOCK_AUX_LAST +#define CLOCK_AUX_LAST (CLOCK_AUX + MAX_AUX_CLOCKS - 1) +#endif + +__attribute__((unused)) +static inline const char *clock_name(clockid_t clockid) +{ + switch (clockid) { + case CLOCK_REALTIME: + return "CLOCK_REALTIME"; + case CLOCK_MONOTONIC: + return "CLOCK_MONOTONIC"; + case CLOCK_PROCESS_CPUTIME_ID: + return "CLOCK_PROCESS_CPUTIME_ID"; + case CLOCK_THREAD_CPUTIME_ID: + return "CLOCK_THREAD_CPUTIME_ID"; + case CLOCK_MONOTONIC_RAW: + return "CLOCK_MONOTONIC_RAW"; + case CLOCK_REALTIME_COARSE: + return "CLOCK_REALTIME_COARSE"; + case CLOCK_MONOTONIC_COARSE: + return "CLOCK_MONOTONIC_COARSE"; + case CLOCK_BOOTTIME: + return "CLOCK_BOOTTIME"; + case CLOCK_REALTIME_ALARM: + return "CLOCK_REALTIME_ALARM"; + case CLOCK_BOOTTIME_ALARM: + return "CLOCK_BOOTTIME_ALARM"; + case CLOCK_TAI: + return "CLOCK_TAI"; + case CLOCK_AUX + 0: + return "CLOCK_AUX0"; + case CLOCK_AUX + 1: + return "CLOCK_AUX1"; + case CLOCK_AUX + 2: + return "CLOCK_AUX2"; + case CLOCK_AUX + 3: + return "CLOCK_AUX3"; + case CLOCK_AUX + 4: + return "CLOCK_AUX4"; + case CLOCK_AUX + 5: + return "CLOCK_AUX5"; + case CLOCK_AUX + 6: + return "CLOCK_AUX6"; + case CLOCK_AUX + 7: + return "CLOCK_AUX7"; + }; + return "UNKNOWN_CLOCKID"; +} + +#endif /* __CLOCK_HELPERS_H */ -- cgit v1.3.1