Starting with commit v4.14-rc1~60^2^2~1, a SIGFPE signal sent via kill results to wrong values in si_pid and si_uid fields of compat siginfo_t.
This happens due to FPE_FIXME being defined to 0 for sparc, and at the same time siginfo_layout() introduced by the same commit returns SIL_FAULT for SIGFPE if si_code == SI_USER and FPE_FIXME is defined to 0. Fix this regression by removing FPE_FIXME macro and changing all its users to assign FPE_FLTUNK to si_code instead of FPE_FIXME. Note that FPE_FLTUNK is a new macro introduced by commit 266da65e9156d93e1126e185259a4aae68188d0e. Tested with commit v4.16-11958-g16e205cf42da. This bug was found by strace test suite. Link: https://github.com/strace/strace/issues/21 Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic") Thanks-to: Anatoly Pugachev <mator...@gmail.com> Signed-off-by: Dmitry V. Levin <l...@altlinux.org> --- arch/sparc/include/uapi/asm/siginfo.h | 7 ------- arch/sparc/kernel/traps_32.c | 2 +- arch/sparc/kernel/traps_64.c | 2 +- 3 files changed, 2 insertions(+), 9 deletions(-) diff --git a/arch/sparc/include/uapi/asm/siginfo.h b/arch/sparc/include/uapi/asm/siginfo.h index 896ce44..e704955 100644 --- a/arch/sparc/include/uapi/asm/siginfo.h +++ b/arch/sparc/include/uapi/asm/siginfo.h @@ -18,13 +18,6 @@ #define SI_NOINFO 32767 /* no information in siginfo_t */ /* - * SIGFPE si_codes - */ -#ifdef __KERNEL__ -#define FPE_FIXME 0 /* Broken dup of SI_USER */ -#endif /* __KERNEL__ */ - -/* * SIGEMT si_codes */ #define EMT_TAGOVF 1 /* tag overflow */ diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c index b1ed763..33cd35b 100644 --- a/arch/sparc/kernel/traps_32.c +++ b/arch/sparc/kernel/traps_32.c @@ -307,7 +307,7 @@ void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc, info.si_errno = 0; info.si_addr = (void __user *)pc; info.si_trapno = 0; - info.si_code = FPE_FIXME; + info.si_code = FPE_FLTUNK; if ((fsr & 0x1c000) == (1 << 14)) { if (fsr & 0x10) info.si_code = FPE_FLTINV; diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c index 462a21a..e81072a 100644 --- a/arch/sparc/kernel/traps_64.c +++ b/arch/sparc/kernel/traps_64.c @@ -2372,7 +2372,7 @@ static void do_fpe_common(struct pt_regs *regs) info.si_errno = 0; info.si_addr = (void __user *)regs->tpc; info.si_trapno = 0; - info.si_code = FPE_FIXME; + info.si_code = FPE_FLTUNK; if ((fsr & 0x1c000) == (1 << 14)) { if (fsr & 0x10) info.si_code = FPE_FLTINV; -- ldv
