fix(user,group): execute useradd/groupadd via argv instead of /bin/sh -c#31
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ratazzi wants to merge 1 commit into
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fix(user,group): execute useradd/groupadd via argv instead of /bin/sh -c#31ratazzi wants to merge 1 commit into
ratazzi wants to merge 1 commit into
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User and group management commands were built as shell strings and run through /bin/sh -c. The username/group name was interpolated without any quoting, and comment/home/shell/password were wrapped in single quotes without escaping embedded quotes. A resource name like "foo; touch /tmp/pwned" therefore executed the injected command (typically as root), and a benign GECOS comment such as "O'Reilly" broke the command line. Build argv vectors and pass them directly to std.process.run so no field is ever parsed by a shell. This also drops the gpasswd append flag prepend, which produced an invalid duplicated "-a" when append was true. Covers argv construction with tests, including values containing shell metacharacters.
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Problem
The
userandgroupresources built management commands as shell strings and ran them through/bin/sh -c:"foo; touch /tmp/pwned"executed the injected command — typically as root.comment/home/shell/passwordwere wrapped in single quotes without escaping embedded quotes, so a benign GECOS comment likeO'Reillybroke the command line.Fix
Build argv vectors and pass them directly to
std.process.run, so no field is ever parsed by a shell.useradd/usermod/userdel/groupadd/groupmod/groupdel/passwd/gpasswdall accept their flags directly.This also drops the
gpasswdappend-flag prepend, which produced an invalid duplicated-awhenappend truewas set.Testing
;,$(), quotes) which now stay single literal argv elements.zig build test— 12 tests pass (3 new).