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/err.h | 87 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 tools/include/nolibc/err.h (limited to 'tools/include/nolibc/err.h') diff --git a/tools/include/nolibc/err.h b/tools/include/nolibc/err.h new file mode 100644 index 000000000..e22ae87a7 --- /dev/null +++ b/tools/include/nolibc/err.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * formatted error message for NOLIBC + * Copyright (C) 2026 Thomas Weißschuh + */ + +/* make sure to include all global symbols */ +#include "nolibc.h" + +#ifndef _NOLIBC_ERR_H +#define _NOLIBC_ERR_H + +#include "errno.h" +#include "stdarg.h" +#include "sys.h" + +static __attribute__((unused)) +void vwarn(const char *fmt, va_list args) +{ + fprintf(stderr, "%s: ", program_invocation_short_name); + vfprintf(stderr, fmt, args); + fprintf(stderr, ": %m\n"); +} + +static __attribute__((unused)) +void vwarnx(const char *fmt, va_list args) +{ + fprintf(stderr, "%s: ", program_invocation_short_name); + vfprintf(stderr, fmt, args); + fprintf(stderr, "\n"); +} + +static __attribute__((unused)) +void warn(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vwarn(fmt, args); + va_end(args); +} + +static __attribute__((unused)) +void warnx(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vwarnx(fmt, args); + va_end(args); +} + +static __attribute__((noreturn, unused)) +void verr(int eval, const char *fmt, va_list args) +{ + vwarn(fmt, args); + exit(eval); +} + +static __attribute__((noreturn, unused)) +void verrx(int eval, const char *fmt, va_list args) +{ + warnx(fmt, args); + exit(eval); +} + +static __attribute__((noreturn, unused)) +void err(int eval, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + verr(eval, fmt, args); + va_end(args); +} + +static __attribute__((noreturn, unused)) +void errx(int eval, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + verrx(eval, fmt, args); + va_end(args); +} + +#endif /* _NOLIBC_ERR_H */ -- cgit v1.3.1