Uncaught exception when Sentry serializes a stacktrace when CWD was removed

[chodges15]

How do you use Sentry?

Sentry Saas (sentry.io)

Version

2.33.0

Steps to Reproduce

usage: SENTRY_DSN="https://examplePublicKey@o0.ingest.sentry.io/0" ./reproduce_abspath_bug.sh

#!/usr/bin/env bash
#
# reproduce_abspath_bug.sh
#
# Reproduces the “os.path.abspath → FileNotFoundError” bug
# when the current working directory has been deleted.
# -------------------------------------------------------
# Usage:
#   chmod +x reproduce_abspath_bug.sh
#   ./reproduce_abspath_bug.sh "<YOUR_SENTRY_DSN>"
#
# If you don’t care about actually sending the event,
# you can omit the DSN or pass an empty string.

set -euo pipefail

# -------- configuration --------
PY_VER=python3.10
SDK_VERSION=2.33.0
VENV_DIR="$(mktemp -d)"
DSN="${1:-}"            # first CLI arg or empty
# --------------------------------

echo "Creating virtual environment in $VENV_DIR ..."
$PY_VER -m venv "$VENV_DIR"
# shellcheck disable=SC1090
source "$VENV_DIR/bin/activate"

echo "Installing sentry-sdk==$SDK_VERSION ..."
pip install --no-color --quiet "sentry-sdk==$SDK_VERSION"

echo "Running reproduction snippet ..."
$PY_VER - <<'PY'
import os, shutil, tempfile, sentry_sdk, sys

DSN = os.getenv("SENTRY_DSN", "")
if DSN:
    sentry_sdk.init(dsn=DSN)
else:
    print("⚠️  No DSN provided — event will not be sent to Sentry", file=sys.stderr)

tmp = tempfile.mkdtemp()
os.chdir(tmp)           # change into fresh temp dir
shutil.rmtree(tmp)      # delete it behind our back

try:
    raise RuntimeError("boom")
except Exception as exc:
    print("sending to sentry ...")
    sentry_sdk.capture_exception(exc)
PY

echo
echo "✅  Finished. Check the console output above for the FileNotFoundError traceback."
echo "Cleaning up ..."
deactivate
rm -rf "$VENV_DIR"

Expected Result

Sentry should capture and send the original error without raising a secondary exception.

Actual Result

Instead of the original error, Sentry crashes while serialising the stacktrace:

Traceback (most recent call last):
  File "<stdin>", line 14, in <module>
RuntimeError: boom

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 17, in <module>
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/api.py", line 107, in capture_exception
    return Hub.current.capture_exception(error, scope=scope, **scope_args)
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/hub.py", line 386, in capture_exception
    event, hint = event_from_exception(exc_info, client_options=client.options)
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/utils.py", line 888, in event_from_exception
    "values": exceptions_from_error_tuple(
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/utils.py", line 763, in exceptions_from_error_tuple
    single_exception_from_error_tuple(
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/utils.py", line 689, in single_exception_from_error_tuple
    frames = [
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/utils.py", line 690, in <listcomp>
    serialize_frame(
  File "/tmp/tmp.3c3lRZYJ4Q/lib/python3.10/site-packages/sentry_sdk/utils.py", line 618, in serialize_frame
    "abs_path": os.path.abspath(abs_path) if abs_path else None,
  File "/usr/lib/python3.10/posixpath.py", line 384, in abspath
    cwd = os.getcwd()
FileNotFoundError: [Errno 2] No such file or directory

os.path.abspath calls os.getcwd() when given a relative path; if the current working directory has been deleted, getcwd() raises FileNotFoundError, which bubbles up through Sentry’s serialize_frame. Because the built-in C function getcwd does not create its own Python frame, the traceback points only to posixpath.abspath, making diagnosis confusing.

[linear]

PY-1776 Uncaught exception when Sentry serializes a stacktrace when CWD was removed

[szokeasaurusrex]

Hi @chodges15, thanks for raising this issue! I was able to reproduce the problem, but interestingly, could only reproduce it when running the code from this script (as then, the Python file shows as <stdin>) but not if I save it as a .py file and run the code that way.

I think wrapping this line in a try/except should fix this bug:

sentry-python/sentry_sdk/utils.py

Line 596 in 34dcba4

"abs_path": os.path.abspath(abs_path) if abs_path else None,