linux_dsm_epyc7002/include/uapi/asm-generic/siginfo.h
Dave Hansen 49cd53bf14 mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
Stephen Rothwell reported this linux-next build failure:

	http://lkml.kernel.org/r/20160226164406.065a1ffc@canb.auug.org.au

... caused by the Memory Protection Keys patches from the tip tree triggering
a newly introduced build-time sanity check on an ARM build, because they changed
the ABI of siginfo in an unexpected way.

If u64 has a natural alignment of 8 bytes (which is the case on most mainstream
platforms, with the notable exception of x86-32), then the leadup to the
_sifields union matters:

typedef struct siginfo {
        int si_signo;
        int si_errno;
        int si_code;

        union {
	...
        } _sifields;
} __ARCH_SI_ATTRIBUTES siginfo_t;

Note how the first 3 fields give us 12 bytes, so _sifields is not 8
naturally bytes aligned.

Before the _pkey field addition the largest element of _sifields (on
32-bit platforms) was 32 bits. With the u64 added, the minimum alignment
requirement increased to 8 bytes on those (rare) 32-bit platforms. Thus
GCC padded the space after si_code with 4 extra bytes, and shifted all
_sifields offsets by 4 bytes - breaking the ABI of all of those
remaining fields.

On 64-bit platforms this problem was hidden due to _sifields already
having numerous fields with natural 8 bytes alignment (pointers).

To fix this, we replace the u64 with an '__u32'.  The __u32 does not
increase the minimum alignment requirement of the union, and it is
also large enough to store the 16-bit pkey we have today on x86.

Reported-by: Stehen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Stehen Rothwell <sfr@canb.auug.org.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Helge Deller <deller@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-next@vger.kernel.org
Fixes: cd0ea35ff5 ("signals, pkeys: Notify userspace about protection key faults")
Link: http://lkml.kernel.org/r/20160301125451.02C7426D@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-05 15:00:06 +01:00

313 lines
9.2 KiB
C

#ifndef _UAPI_ASM_GENERIC_SIGINFO_H
#define _UAPI_ASM_GENERIC_SIGINFO_H
#include <linux/compiler.h>
#include <linux/types.h>
typedef union sigval {
int sival_int;
void __user *sival_ptr;
} sigval_t;
/*
* This is the size (including padding) of the part of the
* struct siginfo that is before the union.
*/
#ifndef __ARCH_SI_PREAMBLE_SIZE
#define __ARCH_SI_PREAMBLE_SIZE (3 * sizeof(int))
#endif
#define SI_MAX_SIZE 128
#ifndef SI_PAD_SIZE
#define SI_PAD_SIZE ((SI_MAX_SIZE - __ARCH_SI_PREAMBLE_SIZE) / sizeof(int))
#endif
#ifndef __ARCH_SI_UID_T
#define __ARCH_SI_UID_T __kernel_uid32_t
#endif
/*
* The default "si_band" type is "long", as specified by POSIX.
* However, some architectures want to override this to "int"
* for historical compatibility reasons, so we allow that.
*/
#ifndef __ARCH_SI_BAND_T
#define __ARCH_SI_BAND_T long
#endif
#ifndef __ARCH_SI_CLOCK_T
#define __ARCH_SI_CLOCK_T __kernel_clock_t
#endif
#ifndef __ARCH_SI_ATTRIBUTES
#define __ARCH_SI_ATTRIBUTES
#endif
#ifndef HAVE_ARCH_SIGINFO_T
typedef struct siginfo {
int si_signo;
int si_errno;
int si_code;
union {
int _pad[SI_PAD_SIZE];
/* kill() */
struct {
__kernel_pid_t _pid; /* sender's pid */
__ARCH_SI_UID_T _uid; /* sender's uid */
} _kill;
/* POSIX.1b timers */
struct {
__kernel_timer_t _tid; /* timer id */
int _overrun; /* overrun count */
char _pad[sizeof( __ARCH_SI_UID_T) - sizeof(int)];
sigval_t _sigval; /* same as below */
int _sys_private; /* not to be passed to user */
} _timer;
/* POSIX.1b signals */
struct {
__kernel_pid_t _pid; /* sender's pid */
__ARCH_SI_UID_T _uid; /* sender's uid */
sigval_t _sigval;
} _rt;
/* SIGCHLD */
struct {
__kernel_pid_t _pid; /* which child */
__ARCH_SI_UID_T _uid; /* sender's uid */
int _status; /* exit code */
__ARCH_SI_CLOCK_T _utime;
__ARCH_SI_CLOCK_T _stime;
} _sigchld;
/* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
struct {
void __user *_addr; /* faulting insn/memory ref. */
#ifdef __ARCH_SI_TRAPNO
int _trapno; /* TRAP # which caused the signal */
#endif
short _addr_lsb; /* LSB of the reported address */
union {
/* used when si_code=SEGV_BNDERR */
struct {
void __user *_lower;
void __user *_upper;
} _addr_bnd;
/* used when si_code=SEGV_PKUERR */
__u32 _pkey;
};
} _sigfault;
/* SIGPOLL */
struct {
__ARCH_SI_BAND_T _band; /* POLL_IN, POLL_OUT, POLL_MSG */
int _fd;
} _sigpoll;
/* SIGSYS */
struct {
void __user *_call_addr; /* calling user insn */
int _syscall; /* triggering system call number */
unsigned int _arch; /* AUDIT_ARCH_* of syscall */
} _sigsys;
} _sifields;
} __ARCH_SI_ATTRIBUTES siginfo_t;
/* If the arch shares siginfo, then it has SIGSYS. */
#define __ARCH_SIGSYS
#endif
/*
* How these fields are to be accessed.
*/
#define si_pid _sifields._kill._pid
#define si_uid _sifields._kill._uid
#define si_tid _sifields._timer._tid
#define si_overrun _sifields._timer._overrun
#define si_sys_private _sifields._timer._sys_private
#define si_status _sifields._sigchld._status
#define si_utime _sifields._sigchld._utime
#define si_stime _sifields._sigchld._stime
#define si_value _sifields._rt._sigval
#define si_int _sifields._rt._sigval.sival_int
#define si_ptr _sifields._rt._sigval.sival_ptr
#define si_addr _sifields._sigfault._addr
#ifdef __ARCH_SI_TRAPNO
#define si_trapno _sifields._sigfault._trapno
#endif
#define si_addr_lsb _sifields._sigfault._addr_lsb
#define si_lower _sifields._sigfault._addr_bnd._lower
#define si_upper _sifields._sigfault._addr_bnd._upper
#define si_pkey _sifields._sigfault._pkey
#define si_band _sifields._sigpoll._band
#define si_fd _sifields._sigpoll._fd
#ifdef __ARCH_SIGSYS
#define si_call_addr _sifields._sigsys._call_addr
#define si_syscall _sifields._sigsys._syscall
#define si_arch _sifields._sigsys._arch
#endif
#ifndef __KERNEL__
#define __SI_KILL 0
#define __SI_TIMER 0
#define __SI_POLL 0
#define __SI_FAULT 0
#define __SI_CHLD 0
#define __SI_RT 0
#define __SI_MESGQ 0
#define __SI_SYS 0
#define __SI_CODE(T,N) (N)
#endif
/*
* si_code values
* Digital reserves positive values for kernel-generated signals.
*/
#define SI_USER 0 /* sent by kill, sigsend, raise */
#define SI_KERNEL 0x80 /* sent by the kernel from somewhere */
#define SI_QUEUE -1 /* sent by sigqueue */
#define SI_TIMER __SI_CODE(__SI_TIMER,-2) /* sent by timer expiration */
#define SI_MESGQ __SI_CODE(__SI_MESGQ,-3) /* sent by real time mesq state change */
#define SI_ASYNCIO -4 /* sent by AIO completion */
#define SI_SIGIO -5 /* sent by queued SIGIO */
#define SI_TKILL -6 /* sent by tkill system call */
#define SI_DETHREAD -7 /* sent by execve() killing subsidiary threads */
#define SI_FROMUSER(siptr) ((siptr)->si_code <= 0)
#define SI_FROMKERNEL(siptr) ((siptr)->si_code > 0)
/*
* SIGILL si_codes
*/
#define ILL_ILLOPC (__SI_FAULT|1) /* illegal opcode */
#define ILL_ILLOPN (__SI_FAULT|2) /* illegal operand */
#define ILL_ILLADR (__SI_FAULT|3) /* illegal addressing mode */
#define ILL_ILLTRP (__SI_FAULT|4) /* illegal trap */
#define ILL_PRVOPC (__SI_FAULT|5) /* privileged opcode */
#define ILL_PRVREG (__SI_FAULT|6) /* privileged register */
#define ILL_COPROC (__SI_FAULT|7) /* coprocessor error */
#define ILL_BADSTK (__SI_FAULT|8) /* internal stack error */
#define NSIGILL 8
/*
* SIGFPE si_codes
*/
#define FPE_INTDIV (__SI_FAULT|1) /* integer divide by zero */
#define FPE_INTOVF (__SI_FAULT|2) /* integer overflow */
#define FPE_FLTDIV (__SI_FAULT|3) /* floating point divide by zero */
#define FPE_FLTOVF (__SI_FAULT|4) /* floating point overflow */
#define FPE_FLTUND (__SI_FAULT|5) /* floating point underflow */
#define FPE_FLTRES (__SI_FAULT|6) /* floating point inexact result */
#define FPE_FLTINV (__SI_FAULT|7) /* floating point invalid operation */
#define FPE_FLTSUB (__SI_FAULT|8) /* subscript out of range */
#define NSIGFPE 8
/*
* SIGSEGV si_codes
*/
#define SEGV_MAPERR (__SI_FAULT|1) /* address not mapped to object */
#define SEGV_ACCERR (__SI_FAULT|2) /* invalid permissions for mapped object */
#define SEGV_BNDERR (__SI_FAULT|3) /* failed address bound checks */
#define SEGV_PKUERR (__SI_FAULT|4) /* failed protection key checks */
#define NSIGSEGV 4
/*
* SIGBUS si_codes
*/
#define BUS_ADRALN (__SI_FAULT|1) /* invalid address alignment */
#define BUS_ADRERR (__SI_FAULT|2) /* non-existent physical address */
#define BUS_OBJERR (__SI_FAULT|3) /* object specific hardware error */
/* hardware memory error consumed on a machine check: action required */
#define BUS_MCEERR_AR (__SI_FAULT|4)
/* hardware memory error detected in process but not consumed: action optional*/
#define BUS_MCEERR_AO (__SI_FAULT|5)
#define NSIGBUS 5
/*
* SIGTRAP si_codes
*/
#define TRAP_BRKPT (__SI_FAULT|1) /* process breakpoint */
#define TRAP_TRACE (__SI_FAULT|2) /* process trace trap */
#define TRAP_BRANCH (__SI_FAULT|3) /* process taken branch trap */
#define TRAP_HWBKPT (__SI_FAULT|4) /* hardware breakpoint/watchpoint */
#define NSIGTRAP 4
/*
* SIGCHLD si_codes
*/
#define CLD_EXITED (__SI_CHLD|1) /* child has exited */
#define CLD_KILLED (__SI_CHLD|2) /* child was killed */
#define CLD_DUMPED (__SI_CHLD|3) /* child terminated abnormally */
#define CLD_TRAPPED (__SI_CHLD|4) /* traced child has trapped */
#define CLD_STOPPED (__SI_CHLD|5) /* child has stopped */
#define CLD_CONTINUED (__SI_CHLD|6) /* stopped child has continued */
#define NSIGCHLD 6
/*
* SIGPOLL si_codes
*/
#define POLL_IN (__SI_POLL|1) /* data input available */
#define POLL_OUT (__SI_POLL|2) /* output buffers available */
#define POLL_MSG (__SI_POLL|3) /* input message available */
#define POLL_ERR (__SI_POLL|4) /* i/o error */
#define POLL_PRI (__SI_POLL|5) /* high priority input available */
#define POLL_HUP (__SI_POLL|6) /* device disconnected */
#define NSIGPOLL 6
/*
* SIGSYS si_codes
*/
#define SYS_SECCOMP (__SI_SYS|1) /* seccomp triggered */
#define NSIGSYS 1
/*
* sigevent definitions
*
* It seems likely that SIGEV_THREAD will have to be handled from
* userspace, libpthread transmuting it to SIGEV_SIGNAL, which the
* thread manager then catches and does the appropriate nonsense.
* However, everything is written out here so as to not get lost.
*/
#define SIGEV_SIGNAL 0 /* notify via signal */
#define SIGEV_NONE 1 /* other notification: meaningless */
#define SIGEV_THREAD 2 /* deliver via thread creation */
#define SIGEV_THREAD_ID 4 /* deliver to thread */
/*
* This works because the alignment is ok on all current architectures
* but we leave open this being overridden in the future
*/
#ifndef __ARCH_SIGEV_PREAMBLE_SIZE
#define __ARCH_SIGEV_PREAMBLE_SIZE (sizeof(int) * 2 + sizeof(sigval_t))
#endif
#define SIGEV_MAX_SIZE 64
#define SIGEV_PAD_SIZE ((SIGEV_MAX_SIZE - __ARCH_SIGEV_PREAMBLE_SIZE) \
/ sizeof(int))
typedef struct sigevent {
sigval_t sigev_value;
int sigev_signo;
int sigev_notify;
union {
int _pad[SIGEV_PAD_SIZE];
int _tid;
struct {
void (*_function)(sigval_t);
void *_attribute; /* really pthread_attr_t */
} _sigev_thread;
} _sigev_un;
} sigevent_t;
#define sigev_notify_function _sigev_un._sigev_thread._function
#define sigev_notify_attributes _sigev_un._sigev_thread._attribute
#define sigev_notify_thread_id _sigev_un._tid
#endif /* _UAPI_ASM_GENERIC_SIGINFO_H */