fboss2: guard against unset USER env var in getUnixname#1293
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atulya-singh wants to merge 1 commit into
Open
fboss2: guard against unset USER env var in getUnixname#1293atulya-singh wants to merge 1 commit into
atulya-singh wants to merge 1 commit into
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getenv("USER") can return nullptr (e.g. when USER is not set in the
environment), and getUnixname() passed the result straight to strcmp(),
causing a null-pointer dereference / crash. Guard for nullptr and empty
string before the strcmp calls, matching the handling already done in
getUserInfo() above. An empty/unset USER now falls through to the
interactive prompt.
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Pre-submission checklist
pip install -r requirements-dev.txt && pre-commit installpre-commit runSummary
getUnixname()infboss/cli/fboss2/utils/CmdUtilsCommon.cppcallsgetenv("USER")and passes the result directly tostrcmp():getenvreturnsnullptrwhen the variable is not set, sostrcmp(nullptr, ...)is a null-pointer dereference and crashes the CLI. This is inconsistent withgetUserInfo()directly above, which already null-checks the result ofgetenv.This change guards for
nullptrand empty string before thestrcmpcalls. An unset or emptyUSERnow falls through to the existing interactive prompt instead of crashing.Test Plan
pre-commit run --files fboss/cli/fboss2/utils/CmdUtilsCommon.cpp->clang-format ... Passed, all hooks pass.USER=alice-> returnsalice(unchanged)USER=root-> falls through to interactive prompt (unchanged)USERunset / empty -> falls through to interactive prompt (previously crashed)