diff options
| author | cinap_lenrek <cinap_lenrek@felloff.net> | 2019-08-27 03:47:18 +0200 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2019-08-27 03:47:18 +0200 |
| commit | 2149600d129944f60cbc858bc669193af0523409 (patch) | |
| tree | 89cd2d2b36e204bbb50ed2159ebdbf7f2cd7e01c /sys/src/9/kw/trap.c | |
| parent | 128ea44a89c7905612ad2fa5a61a9325ddfb5e1e (diff) | |
kernel: catch execution read fault on SG_NOEXEC segment
fault() now has an additional pc argument that is
used to detect fault on a non-executable segment.
that is, we check on read fault if the segment
has the SG_NOEXEC attribute and the program counter
is within faulting page.
Diffstat (limited to 'sys/src/9/kw/trap.c')
| -rw-r--r-- | sys/src/9/kw/trap.c | 18 |
1 files changed, 1 insertions, 17 deletions
diff --git a/sys/src/9/kw/trap.c b/sys/src/9/kw/trap.c index 131413c11..0ced0bd6e 100644 --- a/sys/src/9/kw/trap.c +++ b/sys/src/9/kw/trap.c @@ -319,8 +319,6 @@ faultarm(Ureg *ureg, uintptr va, int user, int read) { int n, insyscall; char buf[ERRMAX]; - static int cnt, lastpid; - static ulong lastva; if(up == nil) { dumpregs(ureg); @@ -328,21 +326,7 @@ faultarm(Ureg *ureg, uintptr va, int user, int read) } insyscall = up->insyscall; up->insyscall = 1; - - /* this is quite helpful during mmu and cache debugging */ - if(va == lastva && up->pid == lastpid) { - ++cnt; - if (cnt >= 2) - /* fault() isn't fixing the underlying cause */ - panic("fault: %d consecutive faults for va %#lux", - cnt+1, va); - } else { - cnt = 0; - lastva = va; - lastpid = up->pid; - } - - n = fault(va, read); + n = fault(va, ureg->pc, read); if(n < 0){ if(!user){ dumpregs(ureg); |