This commit adds a new mode to call injection. If the runtime.debugPinner
function is available in the target executable it obtains a pinner by
calling it and then uses it to pin the pointers in the results of call
injection.
This allows the code for call injection to be refactored to execute the
calls in the normal order, since it doesn't need to be concerned with having
space on the target's memory to store intermediate values.
Updates #3310
The step command is changed such that when the function being currently
called is a coroutine switch function it will move to the associated
coroutine.
Functions that switch coroutines are currently the next, stop and yield
closures produced by the iter.Pull function.
Initial support for stepping in functions that use the new
range-over-func statement in go1.23.
Does not support:
- inlining
- viewing variables of the enclosing function from a range-over-func
body closure
- the correct way to find the enclosing function from a range-over-func
body closure (but it should work most of the time).
Updates #3733
* Adjust rtype.go script to handle constants moved to internal/abi from
runtime
* Remove tests in service/dap/server_test that relied on knowledge of
the internal layout of channels.
When the users uses a reslice operation load the whole resliced
variable, ignoring the MaxArrayValues setting.
Only apply this when the 'high' part is specified and a literal and the
'low' part is either unspecified or a literal.
Fixes#3600
* proc: use stack machine to evaluate expressions
This commit splits expression evaluation into two parts. The first part (in
pkg/proc/evalop/evalcompile.go) "compiles" as ast.Expr into a list of
instructions (defined in pkg/proc/evalop/ops.go) for a stack machine
(defined by `proc.(*evalStack)`).
The second part is a stack machine (implemented by `proc.(*EvalScope).eval`
and `proc.(*EvalScope).evalOne`) that has two modes of operation: in the
main mode it executes inteructions from the list (by calling `evalOne`), in
the second mode it executes the call injection protocol by calling
`funcCallStep` repeatedly until it either the protocol finishes, needs more
input from the stack machine (to set call arguments) or fails.
This approach has several benefits:
- it is now possible to remove the goroutine we use to evaluate expression
and the channel used to communicate with the Continue loop.
- every time we resume the target to execute the call injection protocol we
need to update several local variables to match the changed state of the
target, this is now done at the top level of the evaluation loop instead of
being hidden inside a recurisive evaluator
- using runtime.Pin to pin addresses returned by an injected call would
allow us to use a more natural evaluation order for function calls, which
would solve some bugs #3310, allow users to inspect values returned by a
call injection #1599 and allow implementing some other features #1465. Doing
this with the recursive evaluator, while keeping backwards compatibility
with versions of Go that do not have runtime.Pin is very hard. However after
this change we can simply conditionally change how compileFunctionCall works
and add some opcodes.
* review round 1
* review round 2
Use the trampoline attribute to detect auto-generated code. This fixes
a bug where stepping into a method of a generic type called through an
interface will take the debugger into an auto-generated wrapper that
does not have a dictionary and using next will step out of the wrapper.
Fixes a bug reported on the #delve channel of the gophers slack server.
* logflags,proc: flag to log stacktrace execution
Add a log flag to write logs about what the stacktracer does.
* proc: read context from sigtrampgo, fixes TestCgoStacktrace2 on 1.21
Changes stacktrace code to read the signal context from the arguments
of sigtrampgo.
Also changes the automatic fatalthrow breakpoint for go 1.21.
In combination these two changes fix TestCgoStacktrace2 on Go 1.21 on
various platforms.
We used to parse the .gopclntab section but removed support in favor of
simply using DWARF debug information, due to lack of C symbols among
other reasons. This makes it impossible to debug stripped binaries,
which some distrubutions ship by default.
Add back in basic support for .gopclntab which survives if the binary
is stripped, allowing for rudimentary debugging such as basic
program navigation, tracing, etc...
* pkg/proc: pad variable mem in extractVarInfoFromEntry
On 64 bit system, the byte size of the following struct is 16:
type myStruct struct {
a int
b uint32
}
But extractVarInfoFromEntry only allocates a mem of 12 bytes for it.
When calling method of this struct with the "call" command, it will
result in this error:
write out of bounds
This patch extends the mem by adding padding bytes to the end of the
mem.
Fixes#3364.
* move the padding logic into newCompositeMemory
Go 1.21 renamed runtime._type to internal/abi.Type and changed the name
of its fields. Update Delve so that it uses the new names for loading
interfaces and generic type parameters.
The loop adding maxAddSeconds to format a time.Time can take multiple
seconds to complete if the time is very far into the future. To avoid
this loop slowing down debugging too much limit it to an arbitrary
maximum.
The chosen maximum is 1000 times the maximum expressible time.Duration,
which is 262 years. This means that we will not format dates beyond
year 262000 AD.
* proc: add a test for dangling unsafe pointers
This new tests checks the behavior when dereferencing dangling pointers.
The behavior does not fully make sense; the test checks the current
behavior for now, which will be improved in subsequent commits.
* proc: populate pointer values
This patch changes how Value and Unreadable are populated for pointer
Variables. Before this patch, variables of kind reflect.Ptr did not have
their Value field populated. This patch populates it in
Variable.loadValue(), which seems natural and consistent with other
types of variables. The Value is the address that the pointer points to.
The Unreadable field was populated inconsistently for pointer variables:
it was never populated for an outer pointer, but it could be populated
for an inner pointer in pointer-to-pointer types. Before this patch,
in pointer whose value could not be read was not easily distinguishable
from a pointer with a value that could be read, but that cannot be
dereferenced (i.e. a dangling pointer): neither of these would be marked
as Unreadable, and both would have a child marked as Unreadable. This
patch makes it so that a pointer variable whose pointer value cannot be
read is marked as Unreadable.
Using this new distinction, this patch fixes a bug around dereferencing
dangling pointers: before, attempting such a dereference produced a
"nil pointer dereference" error. This was bogus, since the pointer was
not nil. Now, we are more discerning and generate a different error.
This patch introduces some changes, particularly to arm64SwitchStack
which fixes the test when running on linux/arm64. The changes causes the
same test to fail on darwin/m1 so temporarily keeping both versions.
Next step should be to refactor and unify the two so they both work with
the same function.
Fixes#2340
* Add support for windows/arm64
* split sentinel files and add winarm64 experiment
* update loadBinaryInfoPE to support PIE binaries
* skip TestDump on windows/arm64
* run windows/arm64 compilation on windows/amd64
* add entry point check for pie binaries
* delete unusded code
* document windows/arm64 breakpoint
* implement changing windows/arm64 fp registers
* update crosscall offset names
* fix G load when using CGO
* fix testvariablescgo
* remove DerefGStructOffset
* derefrence gstructoffset in GStructOffset() if necessary
Go 1.20 switched to uint64 to represent goroutine IDs, we can't
actually follow suit because we have allowed clients to use -1 to refer
to the currently selected goroutine, however we should at least switch
to int64 and also update the rtype check to accept the 1.20 type.
Fix pretty printing for CPU register components (created with the
XMM0.uintN syntax) while using format strings
Also fixes printing large literal constants with format strings.
Fixes#3020
packages
Changes UserCurrent to exclude frames stopped inside the 'internal' and
'runtime/internal' packages of the standard library.
Before this change a goroutine blocked accepting or reading from a
socket would be reported as having a user current frame of:
internal/poll.runtime_pollWait
After this change accepting goroutines will be reported with a user
current frame of:
net.(*netFD).accept
and reading goroutines as:
net.(*netFD).read
Change debug_info type reader and proc to convert parametric types into
their real types by reading the corresponding dictionary entry and
using the same method used for interfaces to retrieve the DIE from a
runtime._type address.
'2586e9b1'.
* pkg/proc: update check for system goroutine
The finalizer goroutine can be either a system goroutine or a user goroutine. It is considered a user goroutine only when it calls back to user code. This change attempts to get closer to the implementation in the src/runtime/traceback.go by checking the value of fingRunning.
We could alternatively adopt the approximation done by src/cmd/trace/trace.go which only special cases "runtime.main", and always considers the finalizer to be a system goroutine.
This patch enables the eBPF tracer backend to parse the ID of the
Goroutine which hit the uprobe. This implementation is specific to AMD64
and will have to be generalized further in order to be used on other
architectures.
Adds a script that check automatically that the the assumptions that
pkg/proc makes about runtime are met by the actual runtime, using a
combination of parsing and magic comments.
Also emits a file describing all the struct fields, constants and
variables of the runtime that we use in pkg/proc.
* proc: move breakpoint condition evaluation out of backends
Moves breakpoint condition evaluation from the point where breakpoints
are set, inside ContinueOnce, to (*Target).Continue.
This accomplishes three things:
1. the breakpoint evaluation method needs not be exported anymore
2. breakpoint condition evaluation can be done with a full scope,
containing a Target object, something that wasn't possible before
because ContinueOnce doesn't have access to the Target object.
3. moves breakpoint condition evaluation out of the critical section
where some of the threads of the target process might be still
running.
* proc/native: handle process death during stop() on Windows
It is possible that the thread dies while we are inside the stop()
function. This results in an Access is denied error being returned by
SuspendThread being called on threads that no longer exist.
Delay the reporting the error from SuspendThread until the end of
stop() and only report it if the thread still exists at that point.
Fixes flakyness with TestIssue1101 that was exacerbated by moving
breakpoint condition evaluation outside of the backends.
