[PATCH RFCv2 07/18] uprobes: Add swbp argument to arch_uretprobe_hijack_return_addr

Jiri Olsa
2025-02-24T14:03:15Z

Adding swbp argument to arch_uretprobe_hijack_return_addr, that
is passed all the way from handle_swbp function, so we can add
extra logic when it's called from syscall in following changes.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
arch/arm/probes/uprobes/core.c | 2 +-
arch/arm64/kernel/probes/uprobes.c | 2 +-
arch/csky/kernel/probes/uprobes.c | 2 +-
arch/loongarch/kernel/uprobes.c | 2 +-
arch/mips/kernel/uprobes.c | 2 +-
arch/powerpc/kernel/uprobes.c | 2 +-
arch/riscv/kernel/probes/uprobes.c | 2 +-
arch/s390/kernel/uprobes.c | 2 +-
arch/sparc/kernel/uprobes.c | 2 +-
arch/x86/kernel/uprobes.c | 2 +-
include/linux/uprobes.h | 3 ++-
kernel/events/uprobes.c | 10 +++++-----
12 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/arch/arm/probes/uprobes/core.c b/arch/arm/probes/uprobes/core.c
index 54a90b565285..4d854a310155 100644
--- a/arch/arm/probes/uprobes/core.c
+++ b/arch/arm/probes/uprobes/core.c
@@ -59,7 +59,7 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)

unsigned long
arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long orig_ret_vaddr;

diff --git a/arch/arm64/kernel/probes/uprobes.c b/arch/arm64/kernel/probes/uprobes.c
index cb3d05af36e3..a38bf900bca1 100644
--- a/arch/arm64/kernel/probes/uprobes.c
+++ b/arch/arm64/kernel/probes/uprobes.c
@@ -156,7 +156,7 @@ bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,

unsigned long
arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long orig_ret_vaddr;

diff --git a/arch/csky/kernel/probes/uprobes.c b/arch/csky/kernel/probes/uprobes.c
index 936bea6fd32d..81a950a73cb6 100644
--- a/arch/csky/kernel/probes/uprobes.c
+++ b/arch/csky/kernel/probes/uprobes.c
@@ -124,7 +124,7 @@ bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,

unsigned long
arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long ra;

diff --git a/arch/loongarch/kernel/uprobes.c b/arch/loongarch/kernel/uprobes.c
index 87abc7137b73..d8b221fafb71 100644
--- a/arch/loongarch/kernel/uprobes.c
+++ b/arch/loongarch/kernel/uprobes.c
@@ -96,7 +96,7 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
}

unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long ra = regs->regs[1];

diff --git a/arch/mips/kernel/uprobes.c b/arch/mips/kernel/uprobes.c
index 401b148f8917..2727bcfd5331 100644
--- a/arch/mips/kernel/uprobes.c
+++ b/arch/mips/kernel/uprobes.c
@@ -196,7 +196,7 @@ void arch_uprobe_abort_xol(struct arch_uprobe *aup,
}

unsigned long arch_uretprobe_hijack_return_addr(
- unsigned long trampoline_vaddr, struct pt_regs *regs)
+ unsigned long trampoline_vaddr, struct pt_regs *regs, bool swbp)
{
unsigned long ra;

diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
index 95a41ae9dfa7..f3b3feb44586 100644
--- a/arch/powerpc/kernel/uprobes.c
+++ b/arch/powerpc/kernel/uprobes.c
@@ -195,7 +195,7 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
}

unsigned long
-arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs)
+arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs, bool swbp)
{
unsigned long orig_ret_vaddr;

diff --git a/arch/riscv/kernel/probes/uprobes.c b/arch/riscv/kernel/probes/uprobes.c
index 4b3dc8beaf77..ef8bc1f6a04e 100644
--- a/arch/riscv/kernel/probes/uprobes.c
+++ b/arch/riscv/kernel/probes/uprobes.c
@@ -128,7 +128,7 @@ bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,

unsigned long
arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long ra;

diff --git a/arch/s390/kernel/uprobes.c b/arch/s390/kernel/uprobes.c
index 5b0633ea8d93..48f79d9a25e9 100644
--- a/arch/s390/kernel/uprobes.c
+++ b/arch/s390/kernel/uprobes.c
@@ -141,7 +141,7 @@ void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
}

unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long orig;

diff --git a/arch/sparc/kernel/uprobes.c b/arch/sparc/kernel/uprobes.c
index 305017bec164..aef4e0ff38f0 100644
--- a/arch/sparc/kernel/uprobes.c
+++ b/arch/sparc/kernel/uprobes.c
@@ -310,7 +310,7 @@ bool arch_uprobe_xol_was_trapped(struct task_struct *t)

unsigned long
arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool swbp)
{
unsigned long orig_ret_vaddr = regs->u_regs[UREG_I7];

diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 22a17c149a55..b06f3cd7551a 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -1180,7 +1180,7 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
}

unsigned long
-arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs)
+arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs, bool swbp)
{
int rasize = sizeof_long(regs), nleft;
unsigned long orig_ret_vaddr = 0; /* clear high bits for 32-bit apps */
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index 1abcae9cde48..6c3c90a0d110 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -221,7 +221,8 @@ extern int arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs);
extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk);
extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data);
extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
-extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs);
+extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs,
+ bool swbp);
extern bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx, struct pt_regs *regs);
extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs);
extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 2b542043089e..cfcde7295e15 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -2207,7 +2207,7 @@ static void cleanup_return_instances(struct uprobe_task *utask, bool chained,
}

static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs,
- struct return_instance *ri)
+ struct return_instance *ri, bool swbp)
{
struct uprobe_task *utask = current->utask;
unsigned long orig_ret_vaddr, trampoline_vaddr;
@@ -2225,7 +2225,7 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs,
}

trampoline_vaddr = uprobe_get_trampoline_vaddr();
- orig_ret_vaddr = arch_uretprobe_hijack_return_addr(trampoline_vaddr, regs);
+ orig_ret_vaddr = arch_uretprobe_hijack_return_addr(trampoline_vaddr, regs, swbp);
if (orig_ret_vaddr == -1)
goto free;

@@ -2503,7 +2503,7 @@ static bool ignore_ret_handler(int rc)
return rc == UPROBE_HANDLER_REMOVE || rc == UPROBE_HANDLER_IGNORE;
}

-static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
+static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs, bool swbp)
{
struct uprobe_consumer *uc;
bool has_consumers = false, remove = true;
@@ -2538,7 +2538,7 @@ static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
utask->auprobe = NULL;

if (!ZERO_OR_NULL_PTR(ri))
- prepare_uretprobe(uprobe, regs, ri);
+ prepare_uretprobe(uprobe, regs, ri, swbp);

if (remove && has_consumers) {
down_read(&uprobe->register_rwsem);
@@ -2720,7 +2720,7 @@ static void handle_swbp(struct pt_regs *regs)
if (arch_uprobe_ignore(&uprobe->arch, regs))
goto out;

- handler_chain(uprobe, regs);
+ handler_chain(uprobe, regs, true);

if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
goto out;
--
2.48.1