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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/firmware/efi/memattr.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'drivers/firmware/efi/memattr.c')
| -rw-r--r-- | drivers/firmware/efi/memattr.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/firmware/efi/memattr.c b/drivers/firmware/efi/memattr.c new file mode 100644 index 000000000..5edbffd4e --- /dev/null +++ b/drivers/firmware/efi/memattr.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2016 Linaro Ltd. <ard.biesheuvel@linaro.org> + */ + +#define pr_fmt(fmt) "efi: memattr: " fmt + +#include <linux/efi.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/memblock.h> + +#include <asm/early_ioremap.h> + +static int __initdata tbl_size; +unsigned long __ro_after_init efi_mem_attr_table = EFI_INVALID_TABLE_ADDR; + +/* + * Reserve the memory associated with the Memory Attributes configuration + * table, if it exists. + */ +void __init efi_memattr_init(void) +{ + efi_memory_attributes_table_t *tbl; + + if (efi_mem_attr_table == EFI_INVALID_TABLE_ADDR) + return; + + tbl = early_memremap(efi_mem_attr_table, sizeof(*tbl)); + if (!tbl) { + pr_err("Failed to map EFI Memory Attributes table @ 0x%lx\n", + efi_mem_attr_table); + return; + } + + if (tbl->version > 2) { + pr_warn("Unexpected EFI Memory Attributes table version %d\n", + tbl->version); + goto unmap; + } + + /* + * The EFI memory attributes table descriptors might potentially be + * smaller than those used by the EFI memory map, as long as they can + * fit a efi_memory_desc_t. However, a larger descriptor size makes no + * sense, and might be an indication that the table is corrupted. + * + * The only exception is kexec_load(), where the EFI memory map is + * reconstructed by user space, and may use a smaller descriptor size + * than the original. Given that, ignoring this companion table is + * still the right thing to do here, but don't complain too loudly when + * this happens. + */ + if (tbl->desc_size < sizeof(efi_memory_desc_t) || + tbl->desc_size > efi.memmap.desc_size) { + pr_warn("Unexpected EFI Memory Attributes descriptor size %u (expected: %lu)\n", + tbl->desc_size, efi.memmap.desc_size); + goto unmap; + } + + /* + * Sanity check: the Memory Attributes Table contains multiple entries + * for each EFI runtime services code or data region in the EFI memory + * map, each with the permission attributes that may be applied when + * mapping the region. There is no upper bound for the number of + * entries, as it could conceivably contain more entries than the EFI + * memory map itself. So pick an arbitrary limit of 64k, which is + * ludicrously high. This prevents a corrupted table from eating all + * system RAM. + */ + if (tbl->num_entries > SZ_64K) { + pr_warn(FW_BUG "Corrupted EFI Memory Attributes Table detected! (version == %u, desc_size == %u, num_entries == %u)\n", + tbl->version, tbl->desc_size, tbl->num_entries); + goto unmap; + } + + tbl_size = sizeof(*tbl) + tbl->num_entries * tbl->desc_size; + memblock_reserve(efi_mem_attr_table, tbl_size); + set_bit(EFI_MEM_ATTR, &efi.flags); + +unmap: + early_memunmap(tbl, sizeof(*tbl)); +} + +/* + * Returns a copy @out of the UEFI memory descriptor @in if it is covered + * entirely by a UEFI memory map entry with matching attributes. The virtual + * address of @out is set according to the matching entry that was found. + */ +static bool entry_is_valid(const efi_memory_desc_t *in, efi_memory_desc_t *out) +{ + u64 in_paddr = in->phys_addr; + u64 in_size = in->num_pages << EFI_PAGE_SHIFT; + efi_memory_desc_t *md; + + *out = *in; + + if (in->type != EFI_RUNTIME_SERVICES_CODE && + in->type != EFI_RUNTIME_SERVICES_DATA) { + pr_warn("Entry type should be RuntimeServiceCode/Data\n"); + return false; + } + + if (PAGE_SIZE > EFI_PAGE_SIZE && + (!PAGE_ALIGNED(in->phys_addr) || + !PAGE_ALIGNED(in->num_pages << EFI_PAGE_SHIFT))) { + /* + * Since arm64 may execute with page sizes of up to 64 KB, the + * UEFI spec mandates that RuntimeServices memory regions must + * be 64 KB aligned. We need to validate this here since we will + * not be able to tighten permissions on such regions without + * affecting adjacent regions. + */ + pr_warn("Entry address region misaligned\n"); + return false; + } + + for_each_efi_memory_desc(md) { + u64 md_paddr = md->phys_addr; + u64 md_size = md->num_pages << EFI_PAGE_SHIFT; + + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == 0 && md->phys_addr != 0) { + /* no virtual mapping has been installed by the stub */ + break; + } + + if (md_paddr > in_paddr || (in_paddr - md_paddr) >= md_size) + continue; + + /* + * This entry covers the start of @in, check whether + * it covers the end as well. + */ + if (md_paddr + md_size < in_paddr + in_size) { + pr_warn("Entry covers multiple EFI memory map regions\n"); + return false; + } + + if (md->type != in->type) { + pr_warn("Entry type deviates from EFI memory map region type\n"); + return false; + } + + out->virt_addr = in_paddr + (md->virt_addr - md_paddr); + + return true; + } + + pr_warn("No matching entry found in the EFI memory map\n"); + return false; +} + +/* + * To be called after the EFI page tables have been populated. If a memory + * attributes table is available, its contents will be used to update the + * mappings with tightened permissions as described by the table. + * This requires the UEFI memory map to have already been populated with + * virtual addresses. + */ +int __init efi_memattr_apply_permissions(struct mm_struct *mm, + efi_memattr_perm_setter fn) +{ + efi_memory_attributes_table_t *tbl; + bool has_bti = false; + int i, ret; + + if (tbl_size <= sizeof(*tbl)) + return 0; + + /* + * We need the EFI memory map to be setup so we can use it to + * lookup the virtual addresses of all entries in the of EFI + * Memory Attributes table. If it isn't available, this + * function should not be called. + */ + if (WARN_ON(!efi_enabled(EFI_MEMMAP))) + return 0; + + tbl = memremap(efi_mem_attr_table, tbl_size, MEMREMAP_WB); + if (!tbl) { + pr_err("Failed to map EFI Memory Attributes table @ 0x%lx\n", + efi_mem_attr_table); + return -ENOMEM; + } + + if (tbl->version > 1 && + (tbl->flags & EFI_MEMORY_ATTRIBUTES_FLAGS_RT_FORWARD_CONTROL_FLOW_GUARD)) + has_bti = true; + + if (efi_enabled(EFI_DBG)) + pr_info("Processing EFI Memory Attributes table:\n"); + + for (i = ret = 0; ret == 0 && i < tbl->num_entries; i++) { + efi_memory_desc_t md; + unsigned long size; + bool valid; + char buf[64]; + + valid = entry_is_valid(efi_memdesc_ptr(tbl->entry, tbl->desc_size, i), + &md); + size = md.num_pages << EFI_PAGE_SHIFT; + if (efi_enabled(EFI_DBG) || !valid) + pr_info("%s 0x%012llx-0x%012llx %s\n", + valid ? "" : "!", md.phys_addr, + md.phys_addr + size - 1, + efi_md_typeattr_format(buf, sizeof(buf), &md)); + + if (valid) { + ret = fn(mm, &md, has_bti); + if (ret) + pr_err("Error updating mappings, skipping subsequent md's\n"); + } + } + memunmap(tbl); + return ret; +} |
