diff options
| author | Jiri Olsa <jolsa@kernel.org> | 2025-07-20 13:21:15 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2025-08-21 20:09:19 +0200 |
| commit | f8b7c528b4fb7018d12b6bb63bb52576cfc73697 (patch) | |
| tree | 5671a99547ad50f68bb5ab7deb2b4643e727c15a /kernel | |
| parent | uprobes: Add uprobe_write function (diff) | |
| download | linux-f8b7c528b4fb7018d12b6bb63bb52576cfc73697.tar.gz linux-f8b7c528b4fb7018d12b6bb63bb52576cfc73697.zip | |
uprobes: Add nbytes argument to uprobe_write
Adding nbytes argument to uprobe_write and related functions as
preparation for writing whole instructions in following changes.
Also renaming opcode arguments to insn, which seems to fit better.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250720112133.244369-6-jolsa@kernel.org
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 838ac40e91e6..c133fd4b492d 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -191,7 +191,8 @@ static void copy_to_page(struct page *page, unsigned long vaddr, const void *src kunmap_atomic(kaddr); } -static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode) +static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *insn, + int nbytes) { uprobe_opcode_t old_opcode; bool is_swbp; @@ -208,7 +209,7 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t uprobe_copy_from_page(page, vaddr, &old_opcode, UPROBE_SWBP_INSN_SIZE); is_swbp = is_swbp_insn(&old_opcode); - if (is_swbp_insn(new_opcode)) { + if (is_swbp_insn(insn)) { if (is_swbp) /* register: already installed? */ return 0; } else { @@ -401,10 +402,10 @@ static bool orig_page_is_identical(struct vm_area_struct *vma, static int __uprobe_write(struct vm_area_struct *vma, struct folio_walk *fw, struct folio *folio, - unsigned long opcode_vaddr, uprobe_opcode_t opcode) + unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes) { - const unsigned long vaddr = opcode_vaddr & PAGE_MASK; - const bool is_register = !!is_swbp_insn(&opcode); + const unsigned long vaddr = insn_vaddr & PAGE_MASK; + const bool is_register = !!is_swbp_insn(insn); bool pmd_mappable; /* For now, we'll only handle PTE-mapped folios. */ @@ -429,7 +430,7 @@ static int __uprobe_write(struct vm_area_struct *vma, */ flush_cache_page(vma, vaddr, pte_pfn(fw->pte)); fw->pte = ptep_clear_flush(vma, vaddr, fw->ptep); - copy_to_page(fw->page, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE); + copy_to_page(fw->page, insn_vaddr, insn, nbytes); /* * When unregistering, we may only zap a PTE if uffd is disabled and @@ -488,13 +489,14 @@ remap: int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, const unsigned long opcode_vaddr, uprobe_opcode_t opcode) { - return uprobe_write(auprobe, vma, opcode_vaddr, opcode, verify_opcode); + return uprobe_write(auprobe, vma, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE, verify_opcode); } int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, - const unsigned long opcode_vaddr, uprobe_opcode_t opcode, uprobe_write_verify_t verify) + const unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes, + uprobe_write_verify_t verify) { - const unsigned long vaddr = opcode_vaddr & PAGE_MASK; + const unsigned long vaddr = insn_vaddr & PAGE_MASK; struct mm_struct *mm = vma->vm_mm; struct uprobe *uprobe; int ret, is_register, ref_ctr_updated = 0; @@ -504,7 +506,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, struct folio *folio; struct page *page; - is_register = is_swbp_insn(&opcode); + is_register = is_swbp_insn(insn); uprobe = container_of(auprobe, struct uprobe, arch); if (WARN_ON_ONCE(!is_cow_mapping(vma->vm_flags))) @@ -527,7 +529,7 @@ retry: goto out; folio = page_folio(page); - ret = verify(page, opcode_vaddr, &opcode); + ret = verify(page, insn_vaddr, insn, nbytes); if (ret <= 0) { folio_put(folio); goto out; @@ -566,7 +568,7 @@ retry: /* Walk the page tables again, to perform the actual update. */ if (folio_walk_start(&fw, vma, vaddr, 0)) { if (fw.page == page) - ret = __uprobe_write(vma, &fw, folio, opcode_vaddr, opcode); + ret = __uprobe_write(vma, &fw, folio, insn_vaddr, insn, nbytes); folio_walk_end(&fw, vma); } |