d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix the ABI change of the signal delivered on the access to the page

Browse Source 
with insufficient protection mode.

For the i386 and amd64, create the tunable, machdep.prot_fault_translation,
with the following behaviour:
	0 = autodetect the signal to be delivered on KERN_PROTECTION_FAILURE
	    from vm_fault based on the ELF OSABI note:
		no note or __FreeBSD_version < 700004 - SIGBUS/BUS_PAGE_FAULT
		note, and __FreeBSD_version >= 700004 - SIGSEGV/SEGV_ACCERR
	1 = always SIGBUS/BUS_PAGE_FAULT
	2 = always SIGSEGV/SEGV_ACCERR

This would do mostly automatic correction of ABI breakage, with the exception
of the untaged binaries for 7-CURRENT/RELENG_7 before the note is fixed. For
them, sysctl would allow to run the binary with manual settings.

Discussed with:	portmgr (kris)
PR:		kern/118304
MFC after:	3 days
This commit is contained in:
Konstantin Belousov 2007-12-04 12:33:03 +00:00
parent f231de478e
commit d24031dd0c
2 changed files with 58 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
sys/amd64/amd64/trap.c
View File

@ -144,6 +144,9 @@ SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW,
static int panic_on_nmi = 1;
SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
&panic_on_nmi, 0, "Panic on NMI");
static int prot_fault_translation = 0;
SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW,
&prot_fault_translation, 0, "Select signal to deliver on protection fault");
extern char *syscallnames[];
@ -312,8 +315,32 @@ trap(struct trapframe *frame)
if (i == SIGSEGV)
ucode = SEGV_MAPERR;
else {
i = SIGSEGV; /* XXX hack */
ucode = SEGV_ACCERR;
if (prot_fault_translation == 0) {
/*
* Autodetect.
* This check also covers the images
* without the ABI-tag ELF note.
*/
if (p->p_osrel >= 700004) {
i = SIGSEGV;
ucode = SEGV_ACCERR;
} else {
i = SIGBUS;
ucode = BUS_PAGE_FAULT;
}
} else if (prot_fault_translation == 1) {
/*
* Always compat mode.
*/
i = SIGBUS;
ucode = BUS_PAGE_FAULT;
} else {
/*
* Always SIGSEGV mode.
*/
i = SIGSEGV;
ucode = SEGV_ACCERR;
}
}
break;

31
sys/i386/i386/trap.c
View File

@ -158,6 +158,9 @@ SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW,
static int panic_on_nmi = 1;
SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
&panic_on_nmi, 0, "Panic on NMI");
static int prot_fault_translation = 0;
SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW,
&prot_fault_translation, 0, "Select signal to deliver on protection fault");
extern char *syscallnames[];
@ -375,8 +378,32 @@ trap(struct trapframe *frame)
if (i == SIGSEGV)
ucode = SEGV_MAPERR;
else {
i = SIGSEGV; /* XXX hack */
ucode = SEGV_ACCERR;
if (prot_fault_translation == 0) {
/*
* Autodetect.
* This check also covers the images
* without the ABI-tag ELF note.
*/
if (p->p_osrel >= 700004) {
i = SIGSEGV;
ucode = SEGV_ACCERR;
} else {
i = SIGBUS;
ucode = BUS_PAGE_FAULT;
}
} else if (prot_fault_translation == 1) {
/*
* Always compat mode.
*/
i = SIGBUS;
ucode = BUS_PAGE_FAULT;
} else {
/*
* Always SIGSEGV mode.
*/
i = SIGSEGV;
ucode = SEGV_ACCERR;
}
}
addr = eva;
break;