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/include/nolibc/stdarg.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 tools/include/nolibc/stdarg.h (limited to 'tools/include/nolibc/stdarg.h') diff --git a/tools/include/nolibc/stdarg.h b/tools/include/nolibc/stdarg.h new file mode 100644 index 000000000..c628b5783 --- /dev/null +++ b/tools/include/nolibc/stdarg.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * Variadic argument support for NOLIBC + * Copyright (C) 2005-2020 Rich Felker, et al. + */ + +#ifndef _NOLIBC_STDARG_H +#define _NOLIBC_STDARG_H + +typedef __builtin_va_list va_list; +#define va_start(v, l) __builtin_va_start(v, l) +#define va_end(v) __builtin_va_end(v) +#define va_arg(v, l) __builtin_va_arg(v, l) +#define va_copy(d, s) __builtin_va_copy(d, s) + +#endif /* _NOLIBC_STDARG_H */ -- cgit v1.3.1