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 --- include/uapi/asm-generic/statfs.h | 84 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 include/uapi/asm-generic/statfs.h (limited to 'include/uapi/asm-generic/statfs.h') diff --git a/include/uapi/asm-generic/statfs.h b/include/uapi/asm-generic/statfs.h new file mode 100644 index 000000000..bd35c7619 --- /dev/null +++ b/include/uapi/asm-generic/statfs.h @@ -0,0 +1,84 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_GENERIC_STATFS_H +#define _UAPI_GENERIC_STATFS_H + +#include + + +/* + * Most 64-bit platforms use 'long', while most 32-bit platforms use '__u32'. + * Yes, they differ in signedness as well as size. + * Special cases can override it for themselves -- except for S390x, which + * is just a little too special for us. And MIPS, which I'm not touching + * with a 10' pole. + */ +#ifndef __statfs_word +#if __BITS_PER_LONG == 64 +#define __statfs_word __kernel_long_t +#else +#define __statfs_word __u32 +#endif +#endif + +struct statfs { + __statfs_word f_type; + __statfs_word f_bsize; + __statfs_word f_blocks; + __statfs_word f_bfree; + __statfs_word f_bavail; + __statfs_word f_files; + __statfs_word f_ffree; + __kernel_fsid_t f_fsid; + __statfs_word f_namelen; + __statfs_word f_frsize; + __statfs_word f_flags; + __statfs_word f_spare[4]; +}; + +/* + * ARM needs to avoid the 32-bit padding at the end, for consistency + * between EABI and OABI + */ +#ifndef ARCH_PACK_STATFS64 +#define ARCH_PACK_STATFS64 +#endif + +struct statfs64 { + __statfs_word f_type; + __statfs_word f_bsize; + __u64 f_blocks; + __u64 f_bfree; + __u64 f_bavail; + __u64 f_files; + __u64 f_ffree; + __kernel_fsid_t f_fsid; + __statfs_word f_namelen; + __statfs_word f_frsize; + __statfs_word f_flags; + __statfs_word f_spare[4]; +} ARCH_PACK_STATFS64; + +/* + * IA64 and x86_64 need to avoid the 32-bit padding at the end, + * to be compatible with the i386 ABI + */ +#ifndef ARCH_PACK_COMPAT_STATFS64 +#define ARCH_PACK_COMPAT_STATFS64 +#endif + +struct compat_statfs64 { + __u32 f_type; + __u32 f_bsize; + __u64 f_blocks; + __u64 f_bfree; + __u64 f_bavail; + __u64 f_files; + __u64 f_ffree; + __kernel_fsid_t f_fsid; + __u32 f_namelen; + __u32 f_frsize; + __u32 f_flags; + __u32 f_spare[4]; +} ARCH_PACK_COMPAT_STATFS64; + +#endif /* _UAPI_GENERIC_STATFS_H */ -- cgit v1.3.1