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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /security/ipe/hooks.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'security/ipe/hooks.c')
| -rw-r--r-- | security/ipe/hooks.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/security/ipe/hooks.c b/security/ipe/hooks.c new file mode 100644 index 000000000..0ae54a880 --- /dev/null +++ b/security/ipe/hooks.c @@ -0,0 +1,342 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved. + */ + +#include <linux/fs.h> +#include <linux/fs_struct.h> +#include <linux/types.h> +#include <linux/binfmts.h> +#include <linux/mman.h> +#include <linux/blk_types.h> + +#include "ipe.h" +#include "hooks.h" +#include "eval.h" +#include "digest.h" + +/** + * ipe_bprm_check_security() - ipe security hook function for bprm check. + * @bprm: Supplies a pointer to a linux_binprm structure to source the file + * being evaluated. + * + * This LSM hook is called when a binary is loaded through the exec + * family of system calls. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_bprm_check_security(struct linux_binprm *bprm) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + + ipe_build_eval_ctx(&ctx, bprm->file, IPE_OP_EXEC, IPE_HOOK_BPRM_CHECK); + return ipe_evaluate_event(&ctx); +} + +/** + * ipe_bprm_creds_for_exec() - ipe security hook function for bprm creds check. + * @bprm: Supplies a pointer to a linux_binprm structure to source the file + * being evaluated. + * + * This LSM hook is called when userspace signals the kernel to check a file + * for execution through the execveat syscall with the AT_EXECVE_CHECK flag. + * The hook triggers IPE policy evaluation on the script file and returns + * the policy decision to userspace. The userspace program receives the + * return code and can decide whether to proceed with script execution. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_bprm_creds_for_exec(struct linux_binprm *bprm) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + + if (!bprm->is_check) + return 0; + + ipe_build_eval_ctx(&ctx, bprm->file, IPE_OP_EXEC, + IPE_HOOK_BPRM_CREDS_FOR_EXEC); + return ipe_evaluate_event(&ctx); +} + +/** + * ipe_mmap_file() - ipe security hook function for mmap check. + * @f: File being mmap'd. Can be NULL in the case of anonymous memory. + * @reqprot: The requested protection on the mmap, passed from usermode. + * @prot: The effective protection on the mmap, resolved from reqprot and + * system configuration. + * @flags: Unused. + * + * This hook is called when a file is loaded through the mmap + * family of system calls. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_mmap_file(struct file *f, unsigned long reqprot __always_unused, + unsigned long prot, unsigned long flags) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + + if (prot & PROT_EXEC) { + ipe_build_eval_ctx(&ctx, f, IPE_OP_EXEC, IPE_HOOK_MMAP); + return ipe_evaluate_event(&ctx); + } + + return 0; +} + +/** + * ipe_file_mprotect() - ipe security hook function for mprotect check. + * @vma: Existing virtual memory area created by mmap or similar. + * @reqprot: The requested protection on the mmap, passed from usermode. + * @prot: The effective protection on the mmap, resolved from reqprot and + * system configuration. + * + * This LSM hook is called when a mmap'd region of memory is changing + * its protections via mprotect. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_file_mprotect(struct vm_area_struct *vma, + unsigned long reqprot __always_unused, + unsigned long prot) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + + /* Already Executable */ + if (vma->vm_flags & VM_EXEC) + return 0; + + if (prot & PROT_EXEC) { + ipe_build_eval_ctx(&ctx, vma->vm_file, IPE_OP_EXEC, IPE_HOOK_MPROTECT); + return ipe_evaluate_event(&ctx); + } + + return 0; +} + +/** + * ipe_kernel_read_file() - ipe security hook function for kernel read. + * @file: Supplies a pointer to the file structure being read in from disk. + * @id: Supplies the enumeration identifying the purpose of the read. + * @contents: Unused. + * + * This LSM hook is called when a file is read from disk in the kernel. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_kernel_read_file(struct file *file, enum kernel_read_file_id id, + bool contents) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + enum ipe_op_type op; + + switch (id) { + case READING_FIRMWARE: + op = IPE_OP_FIRMWARE; + break; + case READING_MODULE: + case READING_MODULE_COMPRESSED: + op = IPE_OP_KERNEL_MODULE; + break; + case READING_KEXEC_INITRAMFS: + op = IPE_OP_KEXEC_INITRAMFS; + break; + case READING_KEXEC_IMAGE: + op = IPE_OP_KEXEC_IMAGE; + break; + case READING_POLICY: + op = IPE_OP_POLICY; + break; + case READING_X509_CERTIFICATE: + op = IPE_OP_X509; + break; + default: + op = IPE_OP_INVALID; + WARN(1, "no rule setup for kernel_read_file enum %d", id); + } + + ipe_build_eval_ctx(&ctx, file, op, IPE_HOOK_KERNEL_READ); + return ipe_evaluate_event(&ctx); +} + +/** + * ipe_kernel_load_data() - ipe security hook function for kernel load data. + * @id: Supplies the enumeration identifying the purpose of the load. + * @contents: Unused. + * + * This LSM hook is called when a data buffer provided by userspace is loading + * into the kernel. + * + * Return: + * * %0 - Success + * * %-EACCES - Did not pass IPE policy + */ +int ipe_kernel_load_data(enum kernel_load_data_id id, bool contents) +{ + struct ipe_eval_ctx ctx = IPE_EVAL_CTX_INIT; + enum ipe_op_type op; + + switch (id) { + case LOADING_FIRMWARE: + op = IPE_OP_FIRMWARE; + break; + case LOADING_MODULE: + op = IPE_OP_KERNEL_MODULE; + break; + case LOADING_KEXEC_INITRAMFS: + op = IPE_OP_KEXEC_INITRAMFS; + break; + case LOADING_KEXEC_IMAGE: + op = IPE_OP_KEXEC_IMAGE; + break; + case LOADING_POLICY: + op = IPE_OP_POLICY; + break; + case LOADING_X509_CERTIFICATE: + op = IPE_OP_X509; + break; + default: + op = IPE_OP_INVALID; + WARN(1, "no rule setup for kernel_load_data enum %d", id); + } + + ipe_build_eval_ctx(&ctx, NULL, op, IPE_HOOK_KERNEL_LOAD); + return ipe_evaluate_event(&ctx); +} + +/** + * ipe_unpack_initramfs() - Mark the current rootfs as initramfs. + */ +void ipe_unpack_initramfs(void) +{ + ipe_sb(current->fs->root.mnt->mnt_sb)->initramfs = true; +} + +#ifdef CONFIG_IPE_PROP_DM_VERITY +/** + * ipe_bdev_free_security() - Free IPE's LSM blob of block_devices. + * @bdev: Supplies a pointer to a block_device that contains the structure + * to free. + */ +void ipe_bdev_free_security(struct block_device *bdev) +{ + struct ipe_bdev *blob = ipe_bdev(bdev); + + ipe_digest_free(blob->root_hash); +} + +#ifdef CONFIG_IPE_PROP_DM_VERITY_SIGNATURE +static void ipe_set_dmverity_signature(struct ipe_bdev *blob, + const void *value, + size_t size) +{ + blob->dm_verity_signed = size > 0 && value; +} +#else +static inline void ipe_set_dmverity_signature(struct ipe_bdev *blob, + const void *value, + size_t size) +{ +} +#endif /* CONFIG_IPE_PROP_DM_VERITY_SIGNATURE */ + +/** + * ipe_bdev_setintegrity() - Save integrity data from a bdev to IPE's LSM blob. + * @bdev: Supplies a pointer to a block_device that contains the LSM blob. + * @type: Supplies the integrity type. + * @value: Supplies the value to store. + * @size: The size of @value. + * + * This hook is currently used to save dm-verity's root hash or the existence + * of a validated signed dm-verity root hash into LSM blob. + * + * Return: %0 on success. If an error occurs, the function will return the + * -errno. + */ +int ipe_bdev_setintegrity(struct block_device *bdev, enum lsm_integrity_type type, + const void *value, size_t size) +{ + const struct dm_verity_digest *digest = NULL; + struct ipe_bdev *blob = ipe_bdev(bdev); + struct digest_info *info = NULL; + + if (type == LSM_INT_DMVERITY_SIG_VALID) { + ipe_set_dmverity_signature(blob, value, size); + + return 0; + } + + if (type != LSM_INT_DMVERITY_ROOTHASH) + return -EINVAL; + + if (!value) { + ipe_digest_free(blob->root_hash); + blob->root_hash = NULL; + + return 0; + } + digest = value; + + info = kzalloc_obj(*info); + if (!info) + return -ENOMEM; + + info->digest = kmemdup(digest->digest, digest->digest_len, GFP_KERNEL); + if (!info->digest) + goto err; + + info->alg = kstrdup(digest->alg, GFP_KERNEL); + if (!info->alg) + goto err; + + info->digest_len = digest->digest_len; + + ipe_digest_free(blob->root_hash); + blob->root_hash = info; + + return 0; +err: + ipe_digest_free(info); + + return -ENOMEM; +} +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + +#ifdef CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG +/** + * ipe_inode_setintegrity() - save integrity data from a inode to IPE's LSM blob. + * @inode: The inode to source the security blob from. + * @type: Supplies the integrity type. + * @value: The value to be stored. + * @size: The size of @value. + * + * This hook is currently used to save the existence of a validated fs-verity + * builtin signature into LSM blob. + * + * Return: %0 on success. If an error occurs, the function will return the + * -errno. + */ +int ipe_inode_setintegrity(const struct inode *inode, + enum lsm_integrity_type type, + const void *value, size_t size) +{ + struct ipe_inode *inode_sec = ipe_inode(inode); + + if (type == LSM_INT_FSVERITY_BUILTINSIG_VALID) { + inode_sec->fs_verity_signed = size > 0 && value; + return 0; + } + + return -EINVAL; +} +#endif /* CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG */ |
