Detect PowerShell 7 or Windows PowerShell before falling back to cmd.exe, and share the selected host shell across agent tools and the interactive shell escape.
Configure UTF-8 output, preserve restricted-sandbox MSYS safeguards, and add Windows coverage for pipelines, workspace writes, and interactive stdin sessions.
* fix(tools): block MSYS and WSL shells under the Windows sandbox
Git-for-Windows bash.exe and sh.exe are MSYS binaries: the MSYS runtime
secures its signal pipe and shared-memory sections with explicit DACLs
granting only the user, Administrators, and SYSTEM (sigproc.cc
sigproc_init -> sec_user_nih), so under the WRITE_RESTRICTED token the
second access check can never pass and startup dies with "couldn't
create signal pipe" or "CreateFileMapping <SID>.1", Win32 error 5. The
System32 WSL bash launcher fails equivalently: the restricted token
cannot connect to the WSL service (Bash/Service/CreateInstance/
E_ACCESSDENIED). Every executable a bare bash can resolve to fails, so
block bash and sh preflight like the MSYS coreutils from #476, mention
the indirect spawn paths (git hooks, git/gh credential helpers) in the
shared suggestion, detect the WSL launcher's UTF-16LE service-denied
stderr, and document the root cause in the runner's KNOWN LIMITATION
comment beside the Schannel note.
* fix(tui): align picker_test switchProviderModel call with 4-value return
* test(tools): cover sh.exe in Windows shell blocking test
* fix(tools): block MSYS coreutils under Windows sandbox
Git for Windows usr\bin coreutils (head, grep, cat, ...) are MSYS PE binaries that fail with ACCESS_DENIED and cygheap/signal-pipe errors when Zero runs them in the write-restricted Windows sandbox. Detect and block these commands before execution, surface MSYS runtime failures from stderr, steer agents toward native Zero tools or require_escalated, and exclude MSYS-prone names from known-safe command tails.
Refs #458
* fix(tools): anchor the last MSYS failure heuristic to MSYS markers
CodeRabbit review feedback: the win32-error-5 plus terminating check
had no MSYS-specific anchor, so unrelated access-denied failures could
be mislabeled as windows_msys_sandbox. Require an MSYS marker like the
neighboring checks do.
Co-Authored-By: Claude Fable 5 <[email protected]>
* fix(tools): let escalation bypass the MSYS guard and make detection quote-aware
Addresses jatmn's review on PR #476:
- bash and exec_command called detectShellCommandIssue before resolving
sandbox_permissions into a command engine, so a require_escalated retry of
a blocked command was still hard-blocked by the same preflight check.
Resolve the command engine first and only bypass the windows_msys_sandbox
issue kind when that resolves to true unsandboxed execution; other issue
kinds (real cmd.exe syntax problems) still block regardless of escalation.
- Unify all MSYS-prone command name checks (MsysProneCommandName, the
preflight scan, and transitively command_prefix.go's known-safe guard)
behind one windowsMsysProneNames set. This fixes expr (in the name set but
missing from the old regex alternations, so never proactively flagged) and
ls (hit the older windows_shell_syntax branch first, so it got different
metadata than every other MSYS-prone name).
- Make the preflight scan quote-aware: split the command into cmd.exe-
operator-separated segments respecting double-quote grouping, and only
check the first word of each segment instead of scanning raw text anywhere.
Fixes false positives on quoted text like commit messages or PR comment
bodies that merely mention a coreutil name.
* test(tools): decouple MSYS-guard bypass tests from real command output
TestBashToolRequireEscalatedMsysGuard and
TestExecCommandRequireEscalatedBypassesMsysGuardAfterApproval asserted
shell_issue == "" to prove the require_escalated bypass worked. Once
bypassed, "cat somefile.txt" actually runs unsandboxed, and its real,
PATH-dependent output could trip the unrelated post-execution
detectShellOutputIssue heuristic, failing the assertion for reasons
unrelated to the preflight guard under test.
Assert on the exit_code "-1" sentinel (set only by shellIssueBlockResult)
instead, which directly reflects whether the preflight guard blocked the
command.
* fix(tools): anchor MSYS path detection to command position, fix prefix approval gap
Address jatmn's latest review on PR #476:
- shell_runtime.go: the explicit MSYS binary-path check (usr\bin\,
mingw64\bin\, msys-2.0.dll, cygwin1.dll) ran against the raw command
string, so a quoted mention (e.g. a commit message describing a
usr\bin\head.exe failure) was still hard-blocked. It now runs against
the first word of each operator-separated segment, same as the
coreutil-name check. windowsCommandSegments also stopped treating ;
as a command separator (cmd.exe does not split on ;, unlike bash) and
now respects cmd.exe's ^ escape character, so escaped operators like
echo ^| head are no longer misread as a real head invocation.
- command_prefix.go: proposedCommandPrefix could offer to approve a
single segment (e.g. "ps aux" in "ps aux | head -5") without checking
that every other segment was independently safe. Since approving a
prefix escalates the whole command to bypass the sandbox, an
MSYS-prone or otherwise unsafe segment could ride along uncovered.
It now only proposes a segment as the prefix when every other
segment in the command is known-safe on its own.
Added regression tests for quoted MSYS path mentions, caret-escaped
operators, semicolon text, and the prefix-approval gap.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
* fix(tools): treat redirection as a command boundary, stop using command text as output evidence
Addresses jatmn's latest review on PR #476:
- firstCommandWord only split on whitespace, so cmd.exe redirection
attached directly to a command name (head>out.txt, cat<in.txt,
grep>matches.txt) was read as one word and never matched against the
MSYS-prone name set. It now also stops at < and >.
- detectShellOutputIssue scanned command+output together, so a command
whose own argument text merely quoted an MSYS failure string (e.g. a
gh pr comment --body describing the bug) could be mislabeled after
running even though the real stdout/stderr was unrelated. Removed the
command parameter entirely from detectShellOutputIssue and both call
sites (bash.go, exec_command.go), so the command line can never be
used as post-execution evidence again.
* fix(tools): remove unused truncateHeadTail wrapper
CodeRabbit nitpick: truncateHeadTailWithTotal is called directly
everywhere, so this wrapper is dead code that trips golangci-lint's
unused check and fails CI.
---------
Co-authored-by: Claude Fable 5 <[email protected]>
anandh8x