mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-10-28 12:53:14 +01:00
Mike Rapoport (Microsoft)
0c3beacf68
Several architectures support text patching, but they name the header files that declare patching functions differently. Make all such headers consistently named text-patching.h and add an empty header in asm-generic for architectures that do not support text patching. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport (Microsoft) <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]> # m68k Acked-by: Arnd Bergmann <[email protected]> Reviewed-by: Luis Chamberlain <[email protected]> Tested-by: kdevops <[email protected]> Cc: Andreas Larsson <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Brian Cain <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Dinh Nguyen <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Johannes Berg <[email protected]> Cc: John Paul Adrian Glaubitz <[email protected]> Cc: Kent Overstreet <[email protected]> Cc: Liam R. Howlett <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Masami Hiramatsu (Google) <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Russell King <[email protected]> Cc: Song Liu <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Steven Rostedt (Google) <[email protected]> Cc: Suren Baghdasaryan <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Uladzislau Rezki (Sony) <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
129 lines
2.9 KiB
C
129 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/kernel.h>
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#include <linux/spinlock.h>
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#include <linux/kprobes.h>
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#include <linux/mm.h>
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#include <linux/stop_machine.h>
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#include <asm/cacheflush.h>
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#include <asm/fixmap.h>
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#include <asm/smp_plat.h>
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#include <asm/opcodes.h>
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#include <asm/text-patching.h>
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struct patch {
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void *addr;
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unsigned int insn;
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};
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#ifdef CONFIG_MMU
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static DEFINE_RAW_SPINLOCK(patch_lock);
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static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
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{
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unsigned int uintaddr = (uintptr_t) addr;
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bool module = !core_kernel_text(uintaddr);
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struct page *page;
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if (module && IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
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page = vmalloc_to_page(addr);
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else if (!module && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
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page = virt_to_page(addr);
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else
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return addr;
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if (flags)
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raw_spin_lock_irqsave(&patch_lock, *flags);
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set_fixmap(fixmap, page_to_phys(page));
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return (void *) (__fix_to_virt(fixmap) + (uintaddr & ~PAGE_MASK));
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}
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static void __kprobes patch_unmap(int fixmap, unsigned long *flags)
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{
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clear_fixmap(fixmap);
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if (flags)
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raw_spin_unlock_irqrestore(&patch_lock, *flags);
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}
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#else
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static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
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{
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return addr;
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}
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static void __kprobes patch_unmap(int fixmap, unsigned long *flags) { }
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#endif
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void __kprobes __patch_text_real(void *addr, unsigned int insn, bool remap)
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{
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bool thumb2 = IS_ENABLED(CONFIG_THUMB2_KERNEL);
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unsigned int uintaddr = (uintptr_t) addr;
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bool twopage = false;
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unsigned long flags;
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void *waddr = addr;
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int size;
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if (remap)
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waddr = patch_map(addr, FIX_TEXT_POKE0, &flags);
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if (thumb2 && __opcode_is_thumb16(insn)) {
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*(u16 *)waddr = __opcode_to_mem_thumb16(insn);
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size = sizeof(u16);
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} else if (thumb2 && (uintaddr & 2)) {
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u16 first = __opcode_thumb32_first(insn);
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u16 second = __opcode_thumb32_second(insn);
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u16 *addrh0 = waddr;
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u16 *addrh1 = waddr + 2;
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twopage = (uintaddr & ~PAGE_MASK) == PAGE_SIZE - 2;
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if (twopage && remap)
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addrh1 = patch_map(addr + 2, FIX_TEXT_POKE1, NULL);
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*addrh0 = __opcode_to_mem_thumb16(first);
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*addrh1 = __opcode_to_mem_thumb16(second);
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if (twopage && addrh1 != addr + 2) {
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flush_kernel_vmap_range(addrh1, 2);
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patch_unmap(FIX_TEXT_POKE1, NULL);
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}
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size = sizeof(u32);
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} else {
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if (thumb2)
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insn = __opcode_to_mem_thumb32(insn);
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else
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insn = __opcode_to_mem_arm(insn);
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*(u32 *)waddr = insn;
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size = sizeof(u32);
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}
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if (waddr != addr) {
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flush_kernel_vmap_range(waddr, twopage ? size / 2 : size);
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patch_unmap(FIX_TEXT_POKE0, &flags);
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}
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flush_icache_range((uintptr_t)(addr),
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(uintptr_t)(addr) + size);
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}
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static int __kprobes patch_text_stop_machine(void *data)
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{
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struct patch *patch = data;
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__patch_text(patch->addr, patch->insn);
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return 0;
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}
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void __kprobes patch_text(void *addr, unsigned int insn)
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{
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struct patch patch = {
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.addr = addr,
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.insn = insn,
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};
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stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL);
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}
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