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.
Acked-by: Andrii Nakryiko <and...@kernel.org>
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
include/linux/uprobes.h | 4 ++--
kernel/events/uprobes.c | 26 ++++++++++++++------------
2 files changed, 16 insertions(+), 14 deletions(-)
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index e13382054435..147c4a0a1af9 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -188,7 +188,7 @@ struct uprobes_state {
};
typedef int (*uprobe_write_verify_t)(struct page *page, unsigned long vaddr,
- uprobe_opcode_t *opcode);
+ uprobe_opcode_t *insn, int nbytes);
extern void __init uprobes_init(void);
extern int set_swbp(struct arch_uprobe *aup, struct vm_area_struct *vma,
unsigned long vaddr);
@@ -199,7 +199,7 @@ 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
vm_area_struct *vma, unsigned long vaddr, uprobe_opcode_t);
extern 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);
+ uprobe_opcode_t *insn, int nbytes,
uprobe_write_verify_t verify);
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);
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 777de9b95dd7..f7feb7417a2c 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
@@ -489,13 +490,14 @@ static int __uprobe_write(struct vm_area_struct *vma,
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;
@@ -505,7 +507,7 @@ 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)))
@@ -528,7 +530,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct
vm_area_struct *vma,
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;
@@ -567,7 +569,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct
vm_area_struct *vma,
/* 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);
}
--
2.49.0
