mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-26 02:15:23 +07:00
3234ac664a
Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit90a545e981("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes:90a545e981("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
102 lines
3.6 KiB
C
102 lines
3.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
|
|
#ifndef __LINUX_MAGIC_H__
|
|
#define __LINUX_MAGIC_H__
|
|
|
|
#define ADFS_SUPER_MAGIC 0xadf5
|
|
#define AFFS_SUPER_MAGIC 0xadff
|
|
#define AFS_SUPER_MAGIC 0x5346414F
|
|
#define AUTOFS_SUPER_MAGIC 0x0187
|
|
#define CODA_SUPER_MAGIC 0x73757245
|
|
#define CRAMFS_MAGIC 0x28cd3d45 /* some random number */
|
|
#define CRAMFS_MAGIC_WEND 0x453dcd28 /* magic number with the wrong endianess */
|
|
#define DEBUGFS_MAGIC 0x64626720
|
|
#define SECURITYFS_MAGIC 0x73636673
|
|
#define SELINUX_MAGIC 0xf97cff8c
|
|
#define SMACK_MAGIC 0x43415d53 /* "SMAC" */
|
|
#define RAMFS_MAGIC 0x858458f6 /* some random number */
|
|
#define TMPFS_MAGIC 0x01021994
|
|
#define HUGETLBFS_MAGIC 0x958458f6 /* some random number */
|
|
#define SQUASHFS_MAGIC 0x73717368
|
|
#define ECRYPTFS_SUPER_MAGIC 0xf15f
|
|
#define EFS_SUPER_MAGIC 0x414A53
|
|
#define EROFS_SUPER_MAGIC_V1 0xE0F5E1E2
|
|
#define EXT2_SUPER_MAGIC 0xEF53
|
|
#define EXT3_SUPER_MAGIC 0xEF53
|
|
#define XENFS_SUPER_MAGIC 0xabba1974
|
|
#define EXT4_SUPER_MAGIC 0xEF53
|
|
#define BTRFS_SUPER_MAGIC 0x9123683E
|
|
#define NILFS_SUPER_MAGIC 0x3434
|
|
#define F2FS_SUPER_MAGIC 0xF2F52010
|
|
#define HPFS_SUPER_MAGIC 0xf995e849
|
|
#define ISOFS_SUPER_MAGIC 0x9660
|
|
#define JFFS2_SUPER_MAGIC 0x72b6
|
|
#define XFS_SUPER_MAGIC 0x58465342 /* "XFSB" */
|
|
#define PSTOREFS_MAGIC 0x6165676C
|
|
#define EFIVARFS_MAGIC 0xde5e81e4
|
|
#define HOSTFS_SUPER_MAGIC 0x00c0ffee
|
|
#define OVERLAYFS_SUPER_MAGIC 0x794c7630
|
|
|
|
#define MINIX_SUPER_MAGIC 0x137F /* minix v1 fs, 14 char names */
|
|
#define MINIX_SUPER_MAGIC2 0x138F /* minix v1 fs, 30 char names */
|
|
#define MINIX2_SUPER_MAGIC 0x2468 /* minix v2 fs, 14 char names */
|
|
#define MINIX2_SUPER_MAGIC2 0x2478 /* minix v2 fs, 30 char names */
|
|
#define MINIX3_SUPER_MAGIC 0x4d5a /* minix v3 fs, 60 char names */
|
|
|
|
#define MSDOS_SUPER_MAGIC 0x4d44 /* MD */
|
|
#define NCP_SUPER_MAGIC 0x564c /* Guess, what 0x564c is :-) */
|
|
#define NFS_SUPER_MAGIC 0x6969
|
|
#define OCFS2_SUPER_MAGIC 0x7461636f
|
|
#define OPENPROM_SUPER_MAGIC 0x9fa1
|
|
#define QNX4_SUPER_MAGIC 0x002f /* qnx4 fs detection */
|
|
#define QNX6_SUPER_MAGIC 0x68191122 /* qnx6 fs detection */
|
|
#define AFS_FS_MAGIC 0x6B414653
|
|
|
|
#define REISERFS_SUPER_MAGIC 0x52654973 /* used by gcc */
|
|
/* used by file system utilities that
|
|
look at the superblock, etc. */
|
|
#define REISERFS_SUPER_MAGIC_STRING "ReIsErFs"
|
|
#define REISER2FS_SUPER_MAGIC_STRING "ReIsEr2Fs"
|
|
#define REISER2FS_JR_SUPER_MAGIC_STRING "ReIsEr3Fs"
|
|
|
|
#define SMB_SUPER_MAGIC 0x517B
|
|
#define CGROUP_SUPER_MAGIC 0x27e0eb
|
|
#define CGROUP2_SUPER_MAGIC 0x63677270
|
|
|
|
#define RDTGROUP_SUPER_MAGIC 0x7655821
|
|
|
|
#define STACK_END_MAGIC 0x57AC6E9D
|
|
|
|
#define TRACEFS_MAGIC 0x74726163
|
|
|
|
#define V9FS_MAGIC 0x01021997
|
|
|
|
#define BDEVFS_MAGIC 0x62646576
|
|
#define DAXFS_MAGIC 0x64646178
|
|
#define BINFMTFS_MAGIC 0x42494e4d
|
|
#define DEVPTS_SUPER_MAGIC 0x1cd1
|
|
#define BINDERFS_SUPER_MAGIC 0x6c6f6f70
|
|
#define FUTEXFS_SUPER_MAGIC 0xBAD1DEA
|
|
#define PIPEFS_MAGIC 0x50495045
|
|
#define PROC_SUPER_MAGIC 0x9fa0
|
|
#define SOCKFS_MAGIC 0x534F434B
|
|
#define SYSFS_MAGIC 0x62656572
|
|
#define USBDEVICE_SUPER_MAGIC 0x9fa2
|
|
#define MTD_INODE_FS_MAGIC 0x11307854
|
|
#define ANON_INODE_FS_MAGIC 0x09041934
|
|
#define BTRFS_TEST_MAGIC 0x73727279
|
|
#define NSFS_MAGIC 0x6e736673
|
|
#define BPF_FS_MAGIC 0xcafe4a11
|
|
#define AAFS_MAGIC 0x5a3c69f0
|
|
#define ZONEFS_MAGIC 0x5a4f4653
|
|
|
|
/* Since UDF 2.01 is ISO 13346 based... */
|
|
#define UDF_SUPER_MAGIC 0x15013346
|
|
#define BALLOON_KVM_MAGIC 0x13661366
|
|
#define ZSMALLOC_MAGIC 0x58295829
|
|
#define DMA_BUF_MAGIC 0x444d4142 /* "DMAB" */
|
|
#define DEVMEM_MAGIC 0x454d444d /* "DMEM" */
|
|
#define Z3FOLD_MAGIC 0x33
|
|
#define PPC_CMM_MAGIC 0xc7571590
|
|
|
|
#endif /* __LINUX_MAGIC_H__ */
|