dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted

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 <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 132 insertions, 0 deletions

diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
new file mode 100644
index 000000000..b052ad630
--- /dev/null
+++ b/tools/include/nolibc/stdint.h
@@ -0,0 +1,132 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * Standard definitions and types for NOLIBC
+ * Copyright (C) 2023 Vincent Dagonneau <v@vda.io>
+ */
+
+#ifndef _NOLIBC_STDINT_H
+#define _NOLIBC_STDINT_H
+
+typedef unsigned char       uint8_t;
+typedef   signed char        int8_t;
+typedef unsigned short     uint16_t;
+typedef   signed short      int16_t;
+typedef unsigned int       uint32_t;
+typedef   signed int        int32_t;
+typedef unsigned long long uint64_t;
+typedef   signed long long  int64_t;
+typedef __SIZE_TYPE__        size_t;
+typedef   signed long       ssize_t;
+typedef unsigned long     uintptr_t;
+typedef   signed long      intptr_t;
+typedef   signed long     ptrdiff_t;
+
+typedef   int8_t       int_least8_t;
+typedef  uint8_t      uint_least8_t;
+typedef  int16_t      int_least16_t;
+typedef uint16_t     uint_least16_t;
+typedef  int32_t      int_least32_t;
+typedef uint32_t     uint_least32_t;
+typedef  int64_t      int_least64_t;
+typedef uint64_t     uint_least64_t;
+
+typedef   int8_t        int_fast8_t;
+typedef  uint8_t       uint_fast8_t;
+typedef  ssize_t       int_fast16_t;
+typedef   size_t      uint_fast16_t;
+typedef  ssize_t       int_fast32_t;
+typedef   size_t      uint_fast32_t;
+typedef  int64_t       int_fast64_t;
+typedef uint64_t      uint_fast64_t;
+
+typedef __INTMAX_TYPE__    intmax_t;
+typedef __UINTMAX_TYPE__  uintmax_t;
+
+/* limits of integral types */
+
+#define        INT8_MIN  (-128)
+#define       INT16_MIN  (-32767-1)
+#define       INT32_MIN  (-2147483647-1)
+#define       INT64_MIN  (-9223372036854775807LL-1)
+
+#define        INT8_MAX  (127)
+#define       INT16_MAX  (32767)
+#define       INT32_MAX  (2147483647)
+#define       INT64_MAX  (9223372036854775807LL)
+
+#define       UINT8_MAX  (255)
+#define      UINT16_MAX  (65535)
+#define      UINT32_MAX  (4294967295U)
+#define      UINT64_MAX  (18446744073709551615ULL)
+
+#define  INT_LEAST8_MIN  INT8_MIN
+#define INT_LEAST16_MIN  INT16_MIN
+#define INT_LEAST32_MIN  INT32_MIN
+#define INT_LEAST64_MIN  INT64_MIN
+
+#define  INT_LEAST8_MAX  INT8_MAX
+#define INT_LEAST16_MAX  INT16_MAX
+#define INT_LEAST32_MAX  INT32_MAX
+#define INT_LEAST64_MAX  INT64_MAX
+
+#define  UINT_LEAST8_MAX UINT8_MAX
+#define UINT_LEAST16_MAX UINT16_MAX
+#define UINT_LEAST32_MAX UINT32_MAX
+#define UINT_LEAST64_MAX UINT64_MAX
+
+#define SIZE_MAX         ((size_t)(__LONG_MAX__) * 2 + 1)
+#define INTPTR_MIN       (-__LONG_MAX__ - 1)
+#define INTPTR_MAX       __LONG_MAX__
+#define PTRDIFF_MIN      INTPTR_MIN
+#define PTRDIFF_MAX      INTPTR_MAX
+#define UINTPTR_MAX      SIZE_MAX
+
+#define  INT_FAST8_MIN   INT8_MIN
+#define INT_FAST16_MIN   INTPTR_MIN
+#define INT_FAST32_MIN   INTPTR_MIN
+#define INT_FAST64_MIN   INT64_MIN
+
+#define  INT_FAST8_MAX   INT8_MAX
+#define INT_FAST16_MAX   INTPTR_MAX
+#define INT_FAST32_MAX   INTPTR_MAX
+#define INT_FAST64_MAX   INT64_MAX
+
+#define  UINT_FAST8_MAX  UINT8_MAX
+#define UINT_FAST16_MAX  SIZE_MAX
+#define UINT_FAST32_MAX  SIZE_MAX
+#define UINT_FAST64_MAX  UINT64_MAX
+
+#define INTMAX_MIN       INT64_MIN
+#define INTMAX_MAX       INT64_MAX
+#define UINTMAX_MAX      UINT64_MAX
+
+#ifndef INT_MIN
+#define INT_MIN          (-__INT_MAX__ - 1)
+#endif
+#ifndef INT_MAX
+#define INT_MAX          __INT_MAX__
+#endif
+
+#ifndef LONG_MIN
+#define LONG_MIN         (-__LONG_MAX__ - 1)
+#endif
+#ifndef LONG_MAX
+#define LONG_MAX         __LONG_MAX__
+#endif
+
+#ifndef ULONG_MAX
+#define ULONG_MAX         ((unsigned long)(__LONG_MAX__) * 2 + 1)
+#endif
+
+#ifndef LLONG_MIN
+#define LLONG_MIN         (-__LONG_LONG_MAX__ - 1)
+#endif
+#ifndef LLONG_MAX
+#define LLONG_MAX         __LONG_LONG_MAX__
+#endif
+
+#ifndef ULLONG_MAX
+#define ULLONG_MAX         ((unsigned long long)(__LONG_LONG_MAX__) * 2 + 1)
+#endif
+
+#endif /* _NOLIBC_STDINT_H */