diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/openbsd/init.go | 31 |
1 files changed, 26 insertions, 5 deletions
diff --git a/sys/openbsd/init.go b/sys/openbsd/init.go index 4dfb1a930..e36c8ae8d 100644 --- a/sys/openbsd/init.go +++ b/sys/openbsd/init.go @@ -25,20 +25,41 @@ type arch struct { S_IFCHR uint64 } +const ( + mknodMode = 0 + mknodDev = 1 + + // openbsd:src/etc/etc.amd64/MAKEDEV + devFdMajor = 22 + devNullDevT = 0x0202 +) + +func major(dev uint64) uint64 { + // openbsd:src/sys/sys/types.h + return (dev >> 8) & 0xff +} + func (arch *arch) SanitizeCall(c *prog.Call) { - // Prevent vnodes of type VBAD from being created. Such vnodes will - // likely trigger assertion errors by the kernel. - pos := 1 + argStart := 1 switch c.Meta.CallName { case "mknodat": - pos = 2 + argStart = 2 fallthrough case "mknod": - mode := c.Args[pos].(*prog.ConstArg) + // Prevent vnodes of type VBAD from being created. Such vnodes will + // likely trigger assertion errors by the kernel. + mode := c.Args[argStart+mknodMode].(*prog.ConstArg) if mode.Val&arch.S_IFMT == arch.S_IFMT { mode.Val &^= arch.S_IFMT mode.Val |= arch.S_IFCHR } + // Prevent /dev/fd/X devices from getting created. They interfere + // with kcov data collection and cause corpus explosion. + // https://groups.google.com/d/msg/syzkaller/_IRWeAjVoy4/Akl2XMZTDAAJ + mode = c.Args[argStart+mknodDev].(*prog.ConstArg) + if major(mode.Val) == devFdMajor { + mode.Val = devNullDevT + } default: arch.unix.SanitizeCall(c) } |