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/mac80211/trace.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 net/mac80211/trace.c (limited to 'net/mac80211/trace.c') diff --git a/net/mac80211/trace.c b/net/mac80211/trace.c new file mode 100644 index 000000000..837857261 --- /dev/null +++ b/net/mac80211/trace.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 +/* bug in tracepoint.h, it should include this */ +#include + +/* sparse isn't too happy with all macros... */ +#ifndef __CHECKER__ +#include +#include "driver-ops.h" +#include "debug.h" +#define CREATE_TRACE_POINTS +#include "trace.h" +#include "trace_msg.h" + +#ifdef CONFIG_MAC80211_MESSAGE_TRACING +void __sdata_info(const char *fmt, ...) +{ + struct va_format vaf = { + .fmt = fmt, + }; + va_list args; + + va_start(args, fmt); + vaf.va = &args; + + pr_info("%pV", &vaf); + trace_mac80211_info(&vaf); + va_end(args); +} + +void __sdata_dbg(bool print, const char *fmt, ...) +{ + struct va_format vaf = { + .fmt = fmt, + }; + va_list args; + + va_start(args, fmt); + vaf.va = &args; + + if (print) + pr_debug("%pV", &vaf); + trace_mac80211_dbg(&vaf); + va_end(args); +} + +void __sdata_err(const char *fmt, ...) +{ + struct va_format vaf = { + .fmt = fmt, + }; + va_list args; + + va_start(args, fmt); + vaf.va = &args; + + pr_err("%pV", &vaf); + trace_mac80211_err(&vaf); + va_end(args); +} + +void __wiphy_dbg(struct wiphy *wiphy, bool print, const char *fmt, ...) +{ + struct va_format vaf = { + .fmt = fmt, + }; + va_list args; + + va_start(args, fmt); + vaf.va = &args; + + if (print) + wiphy_dbg(wiphy, "%pV", &vaf); + trace_mac80211_dbg(&vaf); + va_end(args); +} +#endif +#endif -- cgit v1.3.1