diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2017-06-26 23:16:17 +0200 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2017-07-20 02:13:15 +0200 |
| commit | ea1b75cf9138003eee6389b70e654f5865728525 (patch) | |
| tree | 8f211dd50b28dcd7ba73f3e665c1fcacfbb94514 /arch | |
| parent | signal/sparc: Document a conflict with SI_USER with SIGFPE (diff) | |
| download | linux-ea1b75cf9138003eee6389b70e654f5865728525.tar.xz linux-ea1b75cf9138003eee6389b70e654f5865728525.zip | |
signal/mips: Document a conflict with SI_USER with SIGFPE
Setting si_code to __SI_FAULT results in a userspace seeing
an si_code of 0. This is the same si_code as SI_USER. Posix
and common sense requires that SI_USER not be a signal specific
si_code. As such this use of 0 for the si_code is a pretty
horribly broken ABI.
This use of of __SI_FAULT is only a decade old. Which compared
to the other pieces of kernel code that has made this mistake
is almost yesterday.
This is probably worth fixing but I don't know mips well enough
to know what si_code to would be the proper one to use.
Cc: Ralf Baechle <ralf@linux-mips.org>
Ref: 948a34cf3988 ("[MIPS] Maintain si_code field properly for FP exceptions")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/include/uapi/asm/siginfo.h | 7 | ||||
| -rw-r--r-- | arch/mips/kernel/traps.c | 2 |
2 files changed, 8 insertions, 1 deletions
diff --git a/arch/mips/include/uapi/asm/siginfo.h b/arch/mips/include/uapi/asm/siginfo.h index 8069cf766603..9becfd102132 100644 --- a/arch/mips/include/uapi/asm/siginfo.h +++ b/arch/mips/include/uapi/asm/siginfo.h @@ -123,4 +123,11 @@ typedef struct siginfo { #define SI_TIMER __SI_CODE(__SI_TIMER, -3) /* sent by timer expiration */ #define SI_MESGQ __SI_CODE(__SI_MESGQ, -4) /* sent by real time mesq state change */ +/* + * SIGFPE si_codes + */ +#ifdef __KERNEL__ +#define FPE_FIXME (__SI_FAULT|0) /* Broken dup of SI_USER */ +#endif /* __KERNEL__ */ + #endif /* _UAPI_ASM_SIGINFO_H */ diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index b68b4d0726d3..6c9cca9c5341 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -735,7 +735,7 @@ void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr, else if (fcr31 & FPU_CSR_INE_X) si.si_code = FPE_FLTRES; else - si.si_code = __SI_FAULT; + si.si_code = FPE_FIXME; force_sig_info(SIGFPE, &si, tsk); } |