ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign

[ Upstream commit 61bf318eac2c13356f7bd1c6a05421ef504ccc8a ]

In https://bugs.gentoo.org/769614 Dmitry noticed that
`ptrace(PTRACE_GET_SYSCALL_INFO)` does not return error sign properly.

The bug is in mismatch between get/set errors:

static inline long syscall_get_error(struct task_struct *task,
                                     struct pt_regs *regs)
{
        return regs->r10 == -1 ? regs->r8:0;
}

static inline long syscall_get_return_value(struct task_struct *task,
                                            struct pt_regs *regs)
{
        return regs->r8;
}

static inline void syscall_set_return_value(struct task_struct *task,
                                            struct pt_regs *regs,
                                            int error, long val)
{
        if (error) {
                /* error < 0, but ia64 uses > 0 return value */
                regs->r8 = -error;
                regs->r10 = -1;
        } else {
                regs->r8 = val;
                regs->r10 = 0;
        }
}

Tested on v5.10 on rx3600 machine (ia64 9040 CPU).

Link: https://lkml.kernel.org/r/[email protected]
Link: https://bugs.gentoo.org/769614
Signed-off-by: Sergei Trofimovich <[email protected]>
Reported-by: Dmitry V. Levin <[email protected]>
Reviewed-by: Dmitry V. Levin <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
This commit is contained in:
Sergei Trofimovich 2021-03-12 21:08:27 -08:00 • committed by Greg Kroah-Hartman
commit 8aa97ae0f5

View file

@ -32,7 +32,7 @@ static inline void syscall_rollback(struct task_struct *task,
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
return regs->r10 == -1 ? regs->r8:0;
return regs->r10 == -1 ? -regs->r8:0;
}
static inline long syscall_get_return_value(struct task_struct *task,