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Verified Commit 0e2b0d0f authored by jD91mZM2's avatar jD91mZM2
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Fix a few details

parent 3ac1416d
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1 merge request!107Ptrace overhaul & bitflags
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src/arch/x86_64/interrupt/syscall.rs
+ 5
− 4
View file @ 0e2b0d0f
......@@ -22,15 +22,16 @@ macro_rules! with_interrupt_stack {
unsafe fn $wrapped(stack: *mut InterruptStack) {
let _guard = ptrace::set_process_regs(stack);
ptrace::breakpoint_callback(PTRACE_STOP_PRE_SYSCALL, None);
let not_sysemu = ptrace::next_breakpoint().map(|b| b & PTRACE_FLAG_SYSEMU != PTRACE_FLAG_SYSEMU);
let not_sysemu = ptrace::breakpoint_callback(PTRACE_STOP_PRE_SYSCALL, None)
.and_then(|_| ptrace::next_breakpoint().map(|b| b & PTRACE_FLAG_SYSEMU != PTRACE_FLAG_SYSEMU));
if not_sysemu.unwrap_or(true) {
// If not on a sysemu breakpoint
let $stack = &mut *stack;
$stack.scratch.rax = $code;
ptrace::breakpoint_callback(PTRACE_STOP_POST_SYSCALL, None);
}
ptrace::breakpoint_callback(PTRACE_STOP_POST_SYSCALL, None);
}
}
}
......
src/ptrace.rs
+ 13
− 6
View file @ 0e2b0d0f
......@@ -133,6 +133,11 @@ pub fn send_event(event: PtraceEvent) -> Option<()> {
let mut sessions = sessions_mut();
let session = sessions.get_mut(&context.id)?;
let breakpoint = session.breakpoint.as_ref()?;
if event.cause & breakpoint.flags != event.cause {
return None;
}
session.events.push_back(event);
......@@ -209,8 +214,8 @@ pub fn wait(pid: ContextId) -> Result<Option<PtraceEvent>> {
let sessions = sessions();
match sessions.get(&pid) {
Some(session) if session.breakpoint.as_ref().map(|b| !b.reached).unwrap_or(true) => {
if let Some(event) = session.events.front() {
return Ok(Some(event.clone()));
if !session.events.is_empty() {
return Ok(None);
}
Arc::clone(&session.tracer)
},
......@@ -252,21 +257,23 @@ pub fn breakpoint_callback(match_flags: u64, event: Option<PtraceEvent>) -> Opti
let session = sessions.get_mut(&context.id)?;
let breakpoint = session.breakpoint.as_mut()?;
// TODO: How should singlesteps interact with syscalls? How
// does Linux handle this?
if breakpoint.flags & match_flags != match_flags {
return None;
}
session.events.push_back(event.unwrap_or(ptrace_event!(match_flags)));
// Notify nonblocking tracers
if session.events.len() == 1 {
// If the list of events was previously empty, alert now
proc_trigger_event(session.file_id, EVENT_READ);
}
// In case no tracer is waiting, make sure the next one gets
// the memo
breakpoint.reached = true;
session.tracer.notify();
proc_trigger_event(session.file_id, EVENT_WRITE);
(
Arc::clone(&session.tracee),
......
src/scheme/proc.rs
+ 66
− 53
View file @ 0e2b0d0f
......@@ -15,13 +15,14 @@ use crate::{
use alloc::{
collections::BTreeMap,
sync::Arc
sync::Arc,
vec::Vec
};
use core::{
cmp,
mem,
slice,
sync::atomic::{AtomicUsize, Ordering}
sync::atomic::{AtomicUsize, Ordering},
};
use spin::{Mutex, RwLock};
......@@ -30,12 +31,12 @@ enum RegsKind {
Float,
Int
}
#[derive(Clone, Copy)]
#[derive(Clone)]
enum Operation {
Memory(VirtualAddress),
Regs(RegsKind),
Trace {
new_child: Option<ContextId>
clones: Vec<ContextId>
}
}
......@@ -101,24 +102,30 @@ fn try_stop_context<F, T>(pid: ContextId, restart_after: bool, mut callback: F)
}
#[derive(Clone, Copy)]
struct Handle {
flags: usize,
struct Info {
pid: ContextId,
flags: usize,
}
struct Handle {
info: Info,
operation: Operation
}
impl Handle {
fn continue_ignored_child(&mut self) -> Option<()> {
let pid = match self.operation {
Operation::Trace { ref mut new_child } => new_child.take()?,
fn continue_ignored_children(&mut self) -> Option<()> {
let clones = match self.operation {
Operation::Trace { ref mut clones } => clones,
_ => return None
};
if ptrace::is_traced(pid) {
return None;
}
let contexts = context::contexts();
let context = contexts.get(pid)?;
let mut context = context.write();
context.ptrace_stop = false;
for pid in clones.drain(..) {
if ptrace::is_traced(pid) {
return None;
}
if let Some(context) = contexts.get(pid) {
let mut context = context.write();
context.ptrace_stop = false;
}
}
Some(())
}
}
......@@ -154,7 +161,7 @@ impl Scheme for ProcScheme {
Some("regs/float") => Operation::Regs(RegsKind::Float),
Some("regs/int") => Operation::Regs(RegsKind::Int),
Some("trace") => Operation::Trace {
new_child: None
clones: Vec::new()
},
_ => return Err(Error::new(EINVAL))
};
......@@ -209,9 +216,11 @@ impl Scheme for ProcScheme {
}
self.handles.write().insert(id, Arc::new(Mutex::new(Handle {
flags,
pid,
operation
info: Info {
flags,
pid,
},
operation,
})));
Ok(id)
}
......@@ -224,14 +233,14 @@ impl Scheme for ProcScheme {
/// let regs = syscall::dup(trace, "regs/int")?;
/// ```
fn dup(&self, old_id: usize, buf: &[u8]) -> Result<usize> {
let handle = {
let info = {
let handles = self.handles.read();
let handle = handles.get(&old_id).ok_or(Error::new(EBADF))?;
let handle = handle.lock();
*handle
handle.info
};
let mut path = format!("{}/", handle.pid.into()).into_bytes();
let mut path = format!("{}/", info.pid.into()).into_bytes();
path.extend_from_slice(buf);
let (uid, gid) = {
......@@ -241,7 +250,7 @@ impl Scheme for ProcScheme {
(context.euid, context.egid)
};
self.open(&path, handle.flags, uid, gid)
self.open(&path, info.flags, uid, gid)
}
fn seek(&self, id: usize, pos: usize, whence: usize) -> Result<usize> {
......@@ -269,14 +278,13 @@ impl Scheme for ProcScheme {
let handles = self.handles.read();
Arc::clone(handles.get(&id).ok_or(Error::new(EBADF))?)
};
// TODO: Make sure handle can't deadlock
let mut handle = handle.lock();
let pid = handle.pid;
let info = handle.info;
match handle.operation {
Operation::Memory(ref mut offset) => {
let contexts = context::contexts();
let context = contexts.get(pid).ok_or(Error::new(ESRCH))?;
let context = contexts.get(info.pid).ok_or(Error::new(ESRCH))?;
let context = context.read();
ptrace::with_context_memory(&context, *offset, buf.len(), |ptr| {
......@@ -294,7 +302,7 @@ impl Scheme for ProcScheme {
}
let (output, size) = match kind {
RegsKind::Float => with_context(handle.pid, |context| {
RegsKind::Float => with_context(info.pid, |context| {
// NOTE: The kernel will never touch floats
// In the rare case of not having floating
......@@ -303,7 +311,7 @@ impl Scheme for ProcScheme {
let fx = context.arch.get_fx_regs().unwrap_or_default();
Ok((Output { float: fx }, mem::size_of::<FloatRegisters>()))
})?,
RegsKind::Int => try_stop_context(handle.pid, true, |context| match unsafe { ptrace::regs_for(&context) } {
RegsKind::Int => try_stop_context(info.pid, true, |context| match unsafe { ptrace::regs_for(&context) } {
None => {
println!("{}:{}: Couldn't read registers from stopped process", file!(), line!());
Err(Error::new(ENOTRECOVERABLE))
......@@ -325,7 +333,7 @@ impl Scheme for ProcScheme {
Ok(len)
},
Operation::Trace { .. } => {
let read = ptrace::recv_events(handle.pid, unsafe {
let read = ptrace::recv_events(info.pid, unsafe {
slice::from_raw_parts_mut(
buf.as_mut_ptr() as *mut PtraceEvent,
buf.len() / mem::size_of::<PtraceEvent>()
......@@ -344,16 +352,13 @@ impl Scheme for ProcScheme {
Arc::clone(handles.get(&id).ok_or(Error::new(EBADF))?)
};
let mut handle = handle.lock();
handle.continue_ignored_child();
// Some operations borrow Operation:: mutably
let pid = handle.pid;
let flags = handle.flags;
let info = handle.info;
handle.continue_ignored_children();
match handle.operation {
Operation::Memory(ref mut offset) => {
let contexts = context::contexts();
let context = contexts.get(pid).ok_or(Error::new(ESRCH))?;
let context = contexts.get(info.pid).ok_or(Error::new(ESRCH))?;
let context = context.read();
ptrace::with_context_memory(&context, *offset, buf.len(), |ptr| {
......@@ -373,7 +378,7 @@ impl Scheme for ProcScheme {
*(buf as *const _ as *const FloatRegisters)
};
with_context_mut(pid, |context| {
with_context_mut(info.pid, |context| {
// NOTE: The kernel will never touch floats
// Ignore the rare case of floating point
......@@ -391,7 +396,7 @@ impl Scheme for ProcScheme {
*(buf as *const _ as *const IntRegisters)
};
try_stop_context(handle.pid, true, |context| match unsafe { ptrace::regs_for_mut(context) } {
try_stop_context(info.pid, true, |context| match unsafe { ptrace::regs_for_mut(context) } {
None => {
println!("{}:{}: Couldn't read registers from stopped process", file!(), line!());
Err(Error::new(ENOTRECOVERABLE))
......@@ -404,7 +409,7 @@ impl Scheme for ProcScheme {
})
}
},
Operation::Trace { ref mut new_child } => {
Operation::Trace { ref mut clones } => {
if buf.len() < mem::size_of::<u64>() {
return Ok(0);
}
......@@ -415,14 +420,16 @@ impl Scheme for ProcScheme {
let op = u64::from_ne_bytes(bytes);
if op & PTRACE_FLAG_WAIT != PTRACE_FLAG_WAIT || op & PTRACE_STOP_MASK != 0 {
ptrace::cont(pid);
ptrace::cont(info.pid);
}
if op & PTRACE_STOP_MASK != 0 {
ptrace::set_breakpoint(pid, op);
ptrace::set_breakpoint(info.pid, op);
}
if op & PTRACE_STOP_SINGLESTEP == PTRACE_STOP_SINGLESTEP {
try_stop_context(pid, false, |context| {
// try_stop_context with `false` will
// automatically disable ptrace_stop
try_stop_context(info.pid, false, |context| {
match unsafe { ptrace::regs_for_mut(context) } {
// If another CPU is running this process,
// await for it to be stopped and in such
......@@ -437,12 +444,18 @@ impl Scheme for ProcScheme {
}
}
})?;
} else {
// disable ptrace stop
with_context_mut(info.pid, |context| {
context.ptrace_stop = false;
Ok(())
})?;
}
if op & PTRACE_FLAG_WAIT == PTRACE_FLAG_WAIT || flags & O_NONBLOCK != O_NONBLOCK {
if let Some(event) = ptrace::wait(pid)? {
if op & PTRACE_FLAG_WAIT == PTRACE_FLAG_WAIT || info.flags & O_NONBLOCK != O_NONBLOCK {
if let Some(event) = ptrace::wait(info.pid)? {
if event.cause == PTRACE_EVENT_CLONE {
*new_child = Some(ContextId::from(event.a));
clones.push(ContextId::from(event.a));
}
}
}
......@@ -458,8 +471,8 @@ impl Scheme for ProcScheme {
let mut handle = handle.lock();
match cmd {
F_SETFL => { handle.flags = arg; Ok(0) },
F_GETFL => return Ok(handle.flags),
F_SETFL => { handle.info.flags = arg; Ok(0) },
F_GETFL => return Ok(handle.info.flags),
_ => return Err(Error::new(EINVAL))
}
}
......@@ -469,7 +482,7 @@ impl Scheme for ProcScheme {
let handle = handles.get(&id).ok_or(Error::new(EBADF))?;
let handle = handle.lock();
Ok(ptrace::session_fevent_flags(handle.pid).expect("proc (fevent): invalid session"))
Ok(ptrace::session_fevent_flags(handle.info.pid).expect("proc (fevent): invalid session"))
}
fn fpath(&self, id: usize, buf: &mut [u8]) -> Result<usize> {
......@@ -477,7 +490,7 @@ impl Scheme for ProcScheme {
let handle = handles.get(&id).ok_or(Error::new(EBADF))?;
let handle = handle.lock();
let path = format!("proc:{}/{}", handle.pid.into(), match handle.operation {
let path = format!("proc:{}/{}", handle.info.pid.into(), match handle.operation {
Operation::Memory(_) => "mem",
Operation::Regs(RegsKind::Float) => "regs/float",
Operation::Regs(RegsKind::Int) => "regs/int",
......@@ -493,16 +506,16 @@ impl Scheme for ProcScheme {
fn close(&self, id: usize) -> Result<usize> {
let handle = self.handles.write().remove(&id).ok_or(Error::new(EBADF))?;
let mut handle = handle.lock();
handle.continue_ignored_child();
handle.continue_ignored_children();
if let Operation::Trace { .. } = handle.operation {
ptrace::close_session(handle.pid);
ptrace::close_session(handle.info.pid);
if handle.flags & O_EXCL == O_EXCL {
syscall::kill(handle.pid, SIGKILL)?;
if handle.info.flags & O_EXCL == O_EXCL {
syscall::kill(handle.info.pid, SIGKILL)?;
} else {
let contexts = context::contexts();
if let Some(context) = contexts.get(handle.pid) {
if let Some(context) = contexts.get(handle.info.pid) {
let mut context = context.write();
context.ptrace_stop = false;
}
......
syscall @ edf3c008
Compare 52441c28...edf3c008
Subproject commit 52441c28b1daa6f9febf1bc6588b625b167bd2c3
Subproject commit edf3c008dc0a68245a255945d9a70b02c71991a5
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