Hi Guo, Sorry for the noise. I noticed that the patch was submitted with my short handle as the author / Signed-off-by name.
If it is still possible, could you please update it from: hlsong <[email protected]> to: Hanlin Song <[email protected]> Thanks, Hanlin Guo Ren <[email protected]> 于2026年5月21日周四 23:45写道： > > On Thu, May 21, 2026 at 7:34 PM hlsong <[email protected]> wrote: > > > > From: hlsong89 <[email protected]> > > > > The syscall trace path reloads syscall arguments from pt_regs before > > calling the syscall handler. On C-SKY ABIv2, the 5th and 6th syscall > > arguments are prepared as stack arguments before invoking syscallid. > > > > The current code adjusts sp before loading LSAVE_A4 and LSAVE_A5. Since > > those offsets are relative to the original pt_regs base, loading them > > after changing sp fetches the wrong slots. As a result, traced syscalls > > that use the 5th or 6th argument may receive corrupted arguments. > > > > This is visible with mmap2(), which takes six arguments. A small > > PTRACE_SYSCALL reproducer opens a file and maps one page with: > > > > mmap(NULL, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0) > > > > Before the fix, the traced child fails the mmap and exits with 12. > > After the fix, the mapping succeeds and the child exits with 0. > > > > Fix the trace path by loading a4/a5 from pt_regs before changing sp. > > > > Tested on: ck860f, linux-4.19.15, C-SKY abiv2 > > > > Suggested-by: Guo Ren <[email protected]> > > Signed-off-by: hlsong89 <[email protected]> > > --- > > Changes in v2: > > - Use Guo Ren's suggested approach to handle the ABIv2 stack arguments. > > - Tested with the ptrace+mmap reproducer. > > > > arch/csky/kernel/entry.S | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S > > index c68cdcc76..3261f46f2 100644 > > --- a/arch/csky/kernel/entry.S > > +++ b/arch/csky/kernel/entry.S > > @@ -93,11 +93,11 @@ csky_syscall_trace: > > ldw a2, (sp, LSAVE_A2) > > ldw a3, (sp, LSAVE_A3) > > #if defined(__CSKYABIV2__) > > - subi sp, 8 > > ldw r9, (sp, LSAVE_A4) > > + ldw r10, (sp, LSAVE_A5) > > + subi sp, 8 > > stw r9, (sp, 0x0) > > - ldw r9, (sp, LSAVE_A5) > > - stw r9, (sp, 0x4) > > + stw r10, (sp, 0x4) > > jsr syscallid /* Do system call */ > > addi sp, 8 > > #else > > > > base-commit: 5200f5f493f79f14bbdc349e402a40dfb32f23c8 > > -- > > 2.25.1 > > > Applied, thx. > > -- > Best Regards > Guo Ren
