Hi,
The tests regress/sys/kern/siginfo-fault accesses an mmap(2)ed file
behind its end. Then it expects an SIGBUS, but gets an SIGSEGV.
Related commit message is:
Additionally, SIGBUS/BUS_ADRERR should be generated instead of SIGSEGV
for access to file mapped pages that exceed the end of the file.
(Thanks to kettenis@ for suggesting this test.)
I think this description refers to
http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html
Reference to whole pages within the mapping, but beyond the current
length of the object, shall result in a SIGBUS signal.
The attached diff fixes that for amd64 and i386 and the test passes.
ok?
bluhm
Index: arch/amd64/amd64/trap.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/arch/amd64/amd64/trap.c,v
retrieving revision 1.55
diff -u -p -r1.55 trap.c
--- arch/amd64/amd64/trap.c 14 Jul 2017 12:20:32 -0000 1.55
+++ arch/amd64/amd64/trap.c 14 Jul 2017 22:54:28 -0000
@@ -306,6 +306,7 @@ copyfault:
struct vm_map *map;
vm_prot_t ftype;
extern struct vm_map *kernel_map;
+ int signal, sicode;
cr2 = rcr2();
KERNEL_LOCK();
@@ -372,12 +373,14 @@ faultcommon:
map, fa, ftype, error);
goto we_re_toast;
}
+
+ signal = SIGSEGV;
+ sicode = SEGV_MAPERR;
if (error == ENOMEM) {
printf("UVM: pid %d (%s), uid %d killed:"
" out of swap\n", p->p_p->ps_pid, p->p_p->ps_comm,
p->p_ucred ? (int)p->p_ucred->cr_uid : -1);
- sv.sival_ptr = (void *)fa;
- trapsignal(p, SIGKILL, T_PAGEFLT, SEGV_MAPERR, sv);
+ signal = SIGKILL;
} else {
#ifdef TRAP_SIGDEBUG
printf("pid %d (%s): %s at rip %llx addr %llx\n",
@@ -385,10 +388,15 @@ faultcommon:
frame->tf_rip, rcr2());
frame_dump(frame);
#endif
- sv.sival_ptr = (void *)fa;
- trapsignal(p, SIGSEGV, T_PAGEFLT,
- error == EACCES ? SEGV_ACCERR : SEGV_MAPERR, sv);
}
+ if (error == EACCES)
+ sicode = SEGV_ACCERR;
+ if (error == EIO) {
+ signal = SIGBUS;
+ sicode = BUS_ADRERR;
+ }
+ sv.sival_ptr = (void *)fa;
+ trapsignal(p, signal, T_PAGEFLT, sicode, sv);
KERNEL_UNLOCK();
break;
}
Index: arch/i386/i386/trap.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/arch/i386/i386/trap.c,v
retrieving revision 1.131
diff -u -p -r1.131 trap.c
--- arch/i386/i386/trap.c 14 Jul 2017 12:20:32 -0000 1.131
+++ arch/i386/i386/trap.c 14 Jul 2017 22:55:16 -0000
@@ -374,6 +374,7 @@ trap(struct trapframe *frame)
struct vmspace *vm;
struct vm_map *map;
int error;
+ int signal, sicode;
cr2 = rcr2();
KERNEL_LOCK();
@@ -431,9 +432,17 @@ trap(struct trapframe *frame)
map, va, ftype, error);
goto we_re_toast;
}
+
+ signal = SIGSEGV;
+ sicode = SEGV_MAPERR;
+ if (error == EACCES)
+ sicode = SEGV_ACCERR;
+ if (error == EIO) {
+ signal = SIGBUS;
+ sicode = BUS_ADRERR;
+ }
sv.sival_int = fa;
- trapsignal(p, SIGSEGV, vftype,
- error == EACCES ? SEGV_ACCERR : SEGV_MAPERR, sv);
+ trapsignal(p, signal, vftype, sicode, sv);
KERNEL_UNLOCK();
break;
}
Index: uvm/uvm_fault.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/uvm/uvm_fault.c,v
retrieving revision 1.91
diff -u -p -r1.91 uvm_fault.c
--- uvm/uvm_fault.c 16 Sep 2016 01:09:53 -0000 1.91
+++ uvm/uvm_fault.c 14 Jul 2017 22:23:22 -0000
@@ -1032,7 +1032,7 @@ Case2:
}
if (!UVM_ET_ISNOFAULT(ufi.entry))
- return (EACCES); /* XXX i/o error */
+ return (EIO);
uobjpage = PGO_DONTCARE;
promote = TRUE;
