parisc: Report SIGSEGV instead of SIGBUS when running out of stack
authorHelge Deller <deller@gmx.de>
Sun, 2 Jul 2017 20:00:41 +0000 (22:00 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 21 Jul 2017 05:42:20 +0000 (07:42 +0200)
commit 247462316f85a9e0479445c1a4223950b68ffac1 upstream.

When a process runs out of stack the parisc kernel wrongly faults with SIGBUS
instead of the expected SIGSEGV signal.

This example shows how the kernel faults:
do_page_fault() command='a.out' type=15 address=0xfaac2000 in libc-2.24.so[f8308000+16c000]
trap #15: Data TLB miss fault, vm_start = 0xfa2c2000, vm_end = 0xfaac2000

The vma->vm_end value is the first address which does not belong to the vma, so
adjust the check to include vma->vm_end to the range for which to send the
SIGSEGV signal.

This patch unbreaks building the debian libsigsegv package.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/parisc/mm/fault.c

index 040c48f..b6f3b5e 100644 (file)
@@ -366,7 +366,7 @@ bad_area:
                case 15:        /* Data TLB miss fault/Data page fault */
                        /* send SIGSEGV when outside of vma */
                        if (!vma ||
-                           address < vma->vm_start || address > vma->vm_end) {
+                           address < vma->vm_start || address >= vma->vm_end) {
                                si.si_signo = SIGSEGV;
                                si.si_code = SEGV_MAPERR;
                                break;