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/perf/util/time-utils.h | 51 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 tools/perf/util/time-utils.h (limited to 'tools/perf/util/time-utils.h') diff --git a/tools/perf/util/time-utils.h b/tools/perf/util/time-utils.h new file mode 100644 index 000000000..1142b0bdd --- /dev/null +++ b/tools/perf/util/time-utils.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TIME_UTILS_H_ +#define _TIME_UTILS_H_ + +#include +#include +#include + +struct perf_time_interval { + u64 start, end; +}; + +int parse_nsec_time(const char *str, u64 *ptime); + +int perf_time__parse_str(struct perf_time_interval *ptime, const char *ostr); + +int perf_time__percent_parse_str(struct perf_time_interval *ptime_buf, int num, + const char *ostr, u64 start, u64 end); + +struct perf_time_interval *perf_time__range_alloc(const char *ostr, int *size); + +bool perf_time__skip_sample(struct perf_time_interval *ptime, u64 timestamp); + +bool perf_time__ranges_skip_sample(struct perf_time_interval *ptime_buf, + int num, u64 timestamp); + +struct perf_session; + +int perf_time__parse_for_ranges_reltime(const char *str, struct perf_session *session, + struct perf_time_interval **ranges, + int *range_size, int *range_num, + bool reltime); + +int perf_time__parse_for_ranges(const char *str, struct perf_session *session, + struct perf_time_interval **ranges, + int *range_size, int *range_num); + +int timestamp__scnprintf_usec(u64 timestamp, char *buf, size_t sz); +int timestamp__scnprintf_nsec(u64 timestamp, char *buf, size_t sz); + +int fetch_current_timestamp(char *buf, size_t sz); + +static inline unsigned long long rdclock(void) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC, &ts); + return ts.tv_sec * 1000000000ULL + ts.tv_nsec; +} + +#endif -- cgit v1.3.1