diff options
author | Sven Schnelle <svens@stackframe.org> | 2019-06-05 22:32:17 +0200 |
---|---|---|
committer | Helge Deller <deller@gmx.de> | 2019-06-08 12:56:25 +0200 |
commit | 4e87ace902cf0d401376cac89bb6a5239e57fe9f (patch) | |
tree | b3f1f1321081715fbe035fa0ecf3cd1b9e3735de /arch/parisc | |
parent | 79c3ba3206c7680027f61fd4e3d6956a4154bf31 (diff) | |
download | linux-4e87ace902cf0d401376cac89bb6a5239e57fe9f.tar.bz2 |
parisc: add support for patching multiple words
add patch_text_multiple() which allows to patch multiple
text words in memory. This can be used to copy functions.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
-rw-r--r-- | arch/parisc/include/asm/patch.h | 4 | ||||
-rw-r--r-- | arch/parisc/kernel/patch.c | 75 |
2 files changed, 62 insertions, 17 deletions
diff --git a/arch/parisc/include/asm/patch.h b/arch/parisc/include/asm/patch.h index 685b58a13968..400d84c6e504 100644 --- a/arch/parisc/include/asm/patch.h +++ b/arch/parisc/include/asm/patch.h @@ -4,8 +4,10 @@ /* stop machine and patch kernel text */ void patch_text(void *addr, unsigned int insn); +void patch_text_multiple(void *addr, u32 *insn, unsigned int len); /* patch kernel text with machine already stopped (e.g. in kgdb) */ -void __patch_text(void *addr, unsigned int insn); +void __patch_text(void *addr, u32 insn); +void __patch_text_multiple(void *addr, u32 *insn, unsigned int len); #endif diff --git a/arch/parisc/kernel/patch.c b/arch/parisc/kernel/patch.c index cdcd981278b3..70e9997a3f80 100644 --- a/arch/parisc/kernel/patch.c +++ b/arch/parisc/kernel/patch.c @@ -17,15 +17,18 @@ struct patch { void *addr; - unsigned int insn; + u32 *insn; + unsigned int len; }; -static void __kprobes *patch_map(void *addr, int fixmap) -{ +static DEFINE_RAW_SPINLOCK(patch_lock); + +static void __kprobes *patch_map(void *addr, int fixmap, int *need_unmap) unsigned long uintaddr = (uintptr_t) addr; bool module = !core_kernel_text(uintaddr); struct page *page; + *need_unmap = 0; if (module && IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) page = vmalloc_to_page(addr); else if (!module && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) @@ -33,6 +36,7 @@ static void __kprobes *patch_map(void *addr, int fixmap) else return addr; + *need_unmap = 1; set_fixmap(fixmap, page_to_phys(page)); return (void *) (__fix_to_virt(fixmap) + (uintaddr & ~PAGE_MASK)); @@ -43,26 +47,52 @@ static void __kprobes patch_unmap(int fixmap) clear_fixmap(fixmap); } -void __kprobes __patch_text(void *addr, unsigned int insn) +void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len) +{ + unsigned long start = (unsigned long)addr; + unsigned long end = (unsigned long)addr + len; + u32 *p, *fixmap; + int mapped; + + /* Make sure we don't have any aliases in cache */ + flush_kernel_vmap_range(addr, len); + flush_icache_range(start, end); + + p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &mapped); + + while (len >= 4) { + *p++ = *insn++; + addr += sizeof(u32); + len -= sizeof(u32); + if (len && offset_in_page(addr) == 0) { + /* + * We're crossing a page boundary, so + * need to remap + */ + flush_kernel_vmap_range((void *)fixmap, + (p-fixmap) * sizeof(*p)); + if (mapped) + patch_unmap(FIX_TEXT_POKE0); + p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &mapped); + } + } + + flush_kernel_vmap_range((void *)fixmap, (p-fixmap) * sizeof(*p)); + if (mapped) + patch_unmap(FIX_TEXT_POKE0); + flush_icache_range(start, end); +} + +void __kprobes __patch_text(void *addr, u32 insn) { - void *waddr = addr; - int size; - - waddr = patch_map(addr, FIX_TEXT_POKE0); - *(u32 *)waddr = insn; - size = sizeof(u32); - flush_kernel_vmap_range(waddr, size); - patch_unmap(FIX_TEXT_POKE0); - flush_icache_range((uintptr_t)(addr), - (uintptr_t)(addr) + size); + __patch_text_multiple(addr, &insn, sizeof(insn)); } static int __kprobes patch_text_stop_machine(void *data) { struct patch *patch = data; - __patch_text(patch->addr, patch->insn); - + __patch_text_multiple(patch->addr, patch->insn, patch->len); return 0; } @@ -70,7 +100,20 @@ void __kprobes patch_text(void *addr, unsigned int insn) { struct patch patch = { .addr = addr, + .insn = &insn, + .len = sizeof(insn), + }; + + stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL); +} + +void __kprobes patch_text_multiple(void *addr, u32 *insn, unsigned int len) +{ + + struct patch patch = { + .addr = addr, .insn = insn, + .len = len }; stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL); |