Re: [PATCH v12 01/11] signals, sparc: Add signal codes for ADI violations

From: Eric W. Biederman
Date: Wed Feb 21 2018 - 15:59:15 EST


Khalid Aziz <khalid.aziz@xxxxxxxxxx> writes:

> SPARC M7 processor introduces a new feature - Application Data
> Integrity (ADI). ADI allows MMU to catch rogue accesses to memory.
> When a rogue access occurs, MMU blocks the access and raises an
> exception. In response to the exception, kernel sends the offending
> task a SIGSEGV with si_code that indicates the nature of exception.
> This patch adds three new signal codes specific to ADI feature:
>
> 1. ADI is not enabled for the address and task attempted to access
> memory using ADI
> 2. Task attempted to access memory using wrong ADI tag and caused
> a deferred exception.
> 3. Task attempted to access memory using wrong ADI tag and caused
> a precise exception.
>
> Signed-off-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx>
> Cc: Khalid Aziz <khalid@xxxxxxxxxxxxxx>
> Reviewed-by: Anthony Yznaga <anthony.yznaga@xxxxxxxxxx>

Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>

> ---
> v10:
> - Updated si_code definitions to match other definitions
>
> arch/x86/kernel/signal_compat.c | 2 +-
> include/uapi/asm-generic/siginfo.h | 5 ++++-
> 2 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
> index ac057f9b0763..41cf5996a2a9 100644
> --- a/arch/x86/kernel/signal_compat.c
> +++ b/arch/x86/kernel/signal_compat.c
> @@ -27,7 +27,7 @@ static inline void signal_compat_build_tests(void)
> */
> BUILD_BUG_ON(NSIGILL != 11);
> BUILD_BUG_ON(NSIGFPE != 13);
> - BUILD_BUG_ON(NSIGSEGV != 4);
> + BUILD_BUG_ON(NSIGSEGV != 7);
> BUILD_BUG_ON(NSIGBUS != 5);
> BUILD_BUG_ON(NSIGTRAP != 4);
> BUILD_BUG_ON(NSIGCHLD != 6);
> diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
> index 85dc965afd89..e94f03b3ee6f 100644
> --- a/include/uapi/asm-generic/siginfo.h
> +++ b/include/uapi/asm-generic/siginfo.h
> @@ -246,7 +246,10 @@ typedef struct siginfo {
> #else
> # define SEGV_PKUERR 4 /* failed protection key checks */
> #endif
> -#define NSIGSEGV 4
> +#define SEGV_ACCADI 5 /* ADI not enabled for mapped object */
> +#define SEGV_ADIDERR 6 /* Disrupting MCD error */
> +#define SEGV_ADIPERR 7 /* Precise MCD exception */
> +#define NSIGSEGV 7
>
> /*
> * SIGBUS si_codes