From: Sergei Trofimovich <sly...@gentoo.org> [ 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/20210221002554.333076-2-sly...@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <sly...@gentoo.org> Reported-by: Dmitry V. Levin <l...@altlinux.org> Reviewed-by: Dmitry V. Levin <l...@altlinux.org> Cc: John Paul Adrian Glaubitz <glaub...@physik.fu-berlin.de> Cc: Oleg Nesterov <o...@redhat.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Sasha Levin <sas...@kernel.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, -- 2.30.1
