Merging upstream version 6.9.7.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 0 insertions, 262 deletions

diff --git a/arch/arm64/kernel/patch-scs.c b/arch/arm64/kernel/patch-scs.c
deleted file mode 100644
index a1fe4b4ff5..0000000000
--- a/arch/arm64/kernel/patch-scs.c
+++ /dev/null
@@ -1,262 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2022 - Google LLC
- * Author: Ard Biesheuvel <ardb@google.com>
- */
-
-#include <linux/bug.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/linkage.h>
-#include <linux/printk.h>
-#include <linux/types.h>
-
-#include <asm/cacheflush.h>
-#include <asm/scs.h>
-
-//
-// This minimal DWARF CFI parser is partially based on the code in
-// arch/arc/kernel/unwind.c, and on the document below:
-// https://refspecs.linuxbase.org/LSB_4.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html
-//
-
-#define DW_CFA_nop                          0x00
-#define DW_CFA_set_loc                      0x01
-#define DW_CFA_advance_loc1                 0x02
-#define DW_CFA_advance_loc2                 0x03
-#define DW_CFA_advance_loc4                 0x04
-#define DW_CFA_offset_extended              0x05
-#define DW_CFA_restore_extended             0x06
-#define DW_CFA_undefined                    0x07
-#define DW_CFA_same_value                   0x08
-#define DW_CFA_register                     0x09
-#define DW_CFA_remember_state               0x0a
-#define DW_CFA_restore_state                0x0b
-#define DW_CFA_def_cfa                      0x0c
-#define DW_CFA_def_cfa_register             0x0d
-#define DW_CFA_def_cfa_offset               0x0e
-#define DW_CFA_def_cfa_expression           0x0f
-#define DW_CFA_expression                   0x10
-#define DW_CFA_offset_extended_sf           0x11
-#define DW_CFA_def_cfa_sf                   0x12
-#define DW_CFA_def_cfa_offset_sf            0x13
-#define DW_CFA_val_offset                   0x14
-#define DW_CFA_val_offset_sf                0x15
-#define DW_CFA_val_expression               0x16
-#define DW_CFA_lo_user                      0x1c
-#define DW_CFA_negate_ra_state              0x2d
-#define DW_CFA_GNU_args_size                0x2e
-#define DW_CFA_GNU_negative_offset_extended 0x2f
-#define DW_CFA_hi_user                      0x3f
-
-extern const u8 __eh_frame_start[], __eh_frame_end[];
-
-enum {
-	PACIASP		= 0xd503233f,
-	AUTIASP		= 0xd50323bf,
-	SCS_PUSH	= 0xf800865e,
-	SCS_POP		= 0xf85f8e5e,
-};
-
-static void __always_inline scs_patch_loc(u64 loc)
-{
-	u32 insn = le32_to_cpup((void *)loc);
-
-	switch (insn) {
-	case PACIASP:
-		*(u32 *)loc = cpu_to_le32(SCS_PUSH);
-		break;
-	case AUTIASP:
-		*(u32 *)loc = cpu_to_le32(SCS_POP);
-		break;
-	default:
-		/*
-		 * While the DW_CFA_negate_ra_state directive is guaranteed to
-		 * appear right after a PACIASP/AUTIASP instruction, it may
-		 * also appear after a DW_CFA_restore_state directive that
-		 * restores a state that is only partially accurate, and is
-		 * followed by DW_CFA_negate_ra_state directive to toggle the
-		 * PAC bit again. So we permit other instructions here, and ignore
-		 * them.
-		 */
-		return;
-	}
-	dcache_clean_pou(loc, loc + sizeof(u32));
-}
-
-/*
- * Skip one uleb128/sleb128 encoded quantity from the opcode stream. All bytes
- * except the last one have bit #7 set.
- */
-static int __always_inline skip_xleb128(const u8 **opcode, int size)
-{
-	u8 c;
-
-	do {
-		c = *(*opcode)++;
-		size--;
-	} while (c & BIT(7));
-
-	return size;
-}
-
-struct eh_frame {
-	/*
-	 * The size of this frame if 0 < size < U32_MAX, 0 terminates the list.
-	 */
-	u32	size;
-
-	/*
-	 * The first frame is a Common Information Entry (CIE) frame, followed
-	 * by one or more Frame Description Entry (FDE) frames. In the former
-	 * case, this field is 0, otherwise it is the negated offset relative
-	 * to the associated CIE frame.
-	 */
-	u32	cie_id_or_pointer;
-
-	union {
-		struct { // CIE
-			u8	version;
-			u8	augmentation_string[];
-		};
-
-		struct { // FDE
-			s32	initial_loc;
-			s32	range;
-			u8	opcodes[];
-		};
-	};
-};
-
-static int noinstr scs_handle_fde_frame(const struct eh_frame *frame,
-					bool fde_has_augmentation_data,
-					int code_alignment_factor,
-					bool dry_run)
-{
-	int size = frame->size - offsetof(struct eh_frame, opcodes) + 4;
-	u64 loc = (u64)offset_to_ptr(&frame->initial_loc);
-	const u8 *opcode = frame->opcodes;
-
-	if (fde_has_augmentation_data) {
-		int l;
-
-		// assume single byte uleb128_t
-		if (WARN_ON(*opcode & BIT(7)))
-			return -ENOEXEC;
-
-		l = *opcode++;
-		opcode += l;
-		size -= l + 1;
-	}
-
-	/*
-	 * Starting from 'loc', apply the CFA opcodes that advance the location
-	 * pointer, and identify the locations of the PAC instructions.
-	 */
-	while (size-- > 0) {
-		switch (*opcode++) {
-		case DW_CFA_nop:
-		case DW_CFA_remember_state:
-		case DW_CFA_restore_state:
-			break;
-
-		case DW_CFA_advance_loc1:
-			loc += *opcode++ * code_alignment_factor;
-			size--;
-			break;
-
-		case DW_CFA_advance_loc2:
-			loc += *opcode++ * code_alignment_factor;
-			loc += (*opcode++ << 8) * code_alignment_factor;
-			size -= 2;
-			break;
-
-		case DW_CFA_def_cfa:
-		case DW_CFA_offset_extended:
-			size = skip_xleb128(&opcode, size);
-			fallthrough;
-		case DW_CFA_def_cfa_offset:
-		case DW_CFA_def_cfa_offset_sf:
-		case DW_CFA_def_cfa_register:
-		case DW_CFA_same_value:
-		case DW_CFA_restore_extended:
-		case 0x80 ... 0xbf:
-			size = skip_xleb128(&opcode, size);
-			break;
-
-		case DW_CFA_negate_ra_state:
-			if (!dry_run)
-				scs_patch_loc(loc - 4);
-			break;
-
-		case 0x40 ... 0x7f:
-			// advance loc
-			loc += (opcode[-1] & 0x3f) * code_alignment_factor;
-			break;
-
-		case 0xc0 ... 0xff:
-			break;
-
-		default:
-			pr_err("unhandled opcode: %02x in FDE frame %lx\n", opcode[-1], (uintptr_t)frame);
-			return -ENOEXEC;
-		}
-	}
-	return 0;
-}
-
-int noinstr scs_patch(const u8 eh_frame[], int size)
-{
-	const u8 *p = eh_frame;
-
-	while (size > 4) {
-		const struct eh_frame *frame = (const void *)p;
-		bool fde_has_augmentation_data = true;
-		int code_alignment_factor = 1;
-		int ret;
-
-		if (frame->size == 0 ||
-		    frame->size == U32_MAX ||
-		    frame->size > size)
-			break;
-
-		if (frame->cie_id_or_pointer == 0) {
-			const u8 *p = frame->augmentation_string;
-
-			/* a 'z' in the augmentation string must come first */
-			fde_has_augmentation_data = *p == 'z';
-
-			/*
-			 * The code alignment factor is a uleb128 encoded field
-			 * but given that the only sensible values are 1 or 4,
-			 * there is no point in decoding the whole thing.
-			 */
-			p += strlen(p) + 1;
-			if (!WARN_ON(*p & BIT(7)))
-				code_alignment_factor = *p;
-		} else {
-			ret = scs_handle_fde_frame(frame,
-						   fde_has_augmentation_data,
-						   code_alignment_factor,
-						   true);
-			if (ret)
-				return ret;
-			scs_handle_fde_frame(frame, fde_has_augmentation_data,
-					     code_alignment_factor, false);
-		}
-
-		p += sizeof(frame->size) + frame->size;
-		size -= sizeof(frame->size) + frame->size;
-	}
-	return 0;
-}
-
-asmlinkage void __init scs_patch_vmlinux(void)
-{
-	if (!should_patch_pac_into_scs())
-		return;
-
-	WARN_ON(scs_patch(__eh_frame_start, __eh_frame_end - __eh_frame_start));
-	icache_inval_all_pou();
-	isb();
-}