"Dmitry V. Levin" <ldv@xxxxxxxxx> writes:
Similar to syscall_set_arguments() that complements
syscall_get_arguments(), introduce syscall_set_nr()
that complements syscall_get_nr().
syscall_set_nr() is going to be needed along with
syscall_set_arguments() on all HAVE_ARCH_TRACEHOOK
architectures to implement PTRACE_SET_SYSCALL_INFO API.
Signed-off-by: Dmitry V. Levin <ldv@xxxxxxxxx>
---
arch/arc/include/asm/syscall.h | 6 ++++++
arch/arm/include/asm/syscall.h | 12 ++++++++++++
arch/arm64/include/asm/syscall.h | 7 +++++++
arch/hexagon/include/asm/syscall.h | 7 +++++++
arch/loongarch/include/asm/syscall.h | 7 +++++++
arch/m68k/include/asm/syscall.h | 7 +++++++
arch/microblaze/include/asm/syscall.h | 7 +++++++
arch/mips/include/asm/syscall.h | 7 +++++++
arch/nios2/include/asm/syscall.h | 5 +++++
arch/openrisc/include/asm/syscall.h | 6 ++++++
arch/parisc/include/asm/syscall.h | 7 +++++++
arch/powerpc/include/asm/syscall.h | 5 +++++
arch/riscv/include/asm/syscall.h | 7 +++++++
arch/s390/include/asm/syscall.h | 7 +++++++
arch/sh/include/asm/syscall_32.h | 7 +++++++
arch/sparc/include/asm/syscall.h | 7 +++++++
arch/um/include/asm/syscall-generic.h | 5 +++++
arch/x86/include/asm/syscall.h | 7 +++++++
arch/xtensa/include/asm/syscall.h | 7 +++++++
include/asm-generic/syscall.h | 14 ++++++++++++++
20 files changed, 144 insertions(+)
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index b3dd883699e7..1c0e349fd5c9 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -24,6 +24,13 @@ static inline long syscall_get_nr(struct task_struct *task,
(regs->int_code & 0xffff) : -1;
}
+static inline void syscall_set_nr(struct task_struct *task,
+ struct pt_regs *regs,
+ int nr)
+{
I think there should be a
if (!test_pt_regs_flags(regs, PIF_SYSCALL))
return;
before the modification so a user can't accidentally change int_code
when ptrace stopped in a non-syscall path.
+ regs->int_code = (regs->int_code & ~0xffff) | (nr & 0xffff);
+}
+
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
