On Sun, Feb 21, 2021 at 12:25:54AM +0000, Sergei Trofimovich wrote: > 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). > > CC: linux-i...@vger.kernel.org > CC: linux-kernel@vger.kernel.org > CC: Andrew Morton <a...@linux-foundation.org> > Reported-by: Dmitry V. Levin <l...@altlinux.org> > Bug: https://bugs.gentoo.org/769614 > Signed-off-by: Sergei Trofimovich <sly...@gentoo.org> > --- > arch/ia64/include/asm/syscall.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/ia64/include/asm/syscall.h b/arch/ia64/include/asm/syscall.h > index 6c6f16e409a8..0d23c0049301 100644 > --- a/arch/ia64/include/asm/syscall.h > +++ b/arch/ia64/include/asm/syscall.h > @@ -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,
Reviewed-by: Dmitry V. Levin <l...@altlinux.org> -- ldv
