On Tue, Nov 5, 2024 at 5:34 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Adding data argument to uprobe_write_opcode function and passing
> it to newly added arch overloaded functions:
>
> arch_uprobe_verify_opcode
> arch_uprobe_is_register
>
> This way each architecture can provide custmized verification.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> include/linux/uprobes.h | 6 +++++-
> kernel/events/uprobes.c | 25 +++++++++++++++++++------
> 2 files changed, 24 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
> index 7d23a4fee6f4..be306028ed59 100644
> --- a/include/linux/uprobes.h
> +++ b/include/linux/uprobes.h
> @@ -182,7 +182,7 @@ extern bool is_trap_insn(uprobe_opcode_t *insn);
> extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
> extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
> extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> - unsigned long vaddr, uprobe_opcode_t *insn, int len);
> + unsigned long vaddr, uprobe_opcode_t *insn, int len, void *data);
> extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
> extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
> extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);
> @@ -215,6 +215,10 @@ extern void uprobe_handle_trampoline(struct pt_regs *regs);
> extern void *arch_uretprobe_trampoline(unsigned long *psize);
> extern unsigned long uprobe_get_trampoline_vaddr(void);
> extern void uprobe_copy_from_page(struct page *page, unsigned long vaddr, void *dst, int len);
> +extern int uprobe_verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode);
> +extern int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> + uprobe_opcode_t *new_opcode, void *data);
> +extern bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data);
> #else /* !CONFIG_UPROBES */
> struct uprobes_state {
> };
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 3e275717789b..944d9df1f081 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -264,7 +264,13 @@ 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)
> +__weak bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data)
> +{
> + return is_swbp_insn(insn);
> +}
> +
> +int uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> + uprobe_opcode_t *new_opcode)
> {
> uprobe_opcode_t old_opcode;
> bool is_swbp;
> @@ -292,6 +298,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t
> return 1;
> }
>
> +__weak int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> + uprobe_opcode_t *new_opcode, void *data)
why wrapping lines? even original longer code was single line
> +{
> + return uprobe_verify_opcode(page, vaddr, new_opcode);
> +}
> +
> static struct delayed_uprobe *
> delayed_uprobe_check(struct uprobe *uprobe, struct mm_struct *mm)
> {
> @@ -471,7 +483,8 @@ static int update_ref_ctr(struct uprobe *uprobe, struct mm_struct *mm,
> * Return 0 (success) or a negative errno.
> */
> int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> - unsigned long vaddr, uprobe_opcode_t *insn, int len)
> + unsigned long vaddr, uprobe_opcode_t *insn, int len,
> + void *data)
> {
> struct uprobe *uprobe;
> struct page *old_page, *new_page;
> @@ -480,7 +493,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> bool orig_page_huge = false;
> unsigned int gup_flags = FOLL_FORCE;
>
> - is_register = is_swbp_insn(insn);
> + is_register = arch_uprobe_is_register(insn, len, data);
> uprobe = container_of(auprobe, struct uprobe, arch);
>
> retry:
> @@ -491,7 +504,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> if (IS_ERR(old_page))
> return PTR_ERR(old_page);
>
> - ret = verify_opcode(old_page, vaddr, insn);
> + ret = arch_uprobe_verify_opcode(old_page, vaddr, insn, data);
> if (ret <= 0)
> goto put_old;
>
> @@ -584,7 +597,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
> {
> uprobe_opcode_t insn = UPROBE_SWBP_INSN;
>
> - return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE);
> + return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE, NULL);
> }
>
> /**
> @@ -600,7 +613,7 @@ int __weak
> set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
> {
> return uprobe_write_opcode(auprobe, mm, vaddr,
> - (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE);
> + (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE, NULL);
> }
>
> /* uprobe should have guaranteed positive refcount */
> --
> 2.47.0
>
