Module: kamailio Branch: master Commit: 8f6e826576e52270f21c22a7d94b3026cc22c172 URL: https://github.com/kamailio/kamailio/commit/8f6e826576e52270f21c22a7d94b302… Author: Daniel-Constantin Mierla <miconda(a)gmail.com> Committer: Daniel-Constantin Mierla <miconda(a)gmail.com> Date: 2019-09-06T20:35:08+02:00 core: ensure index of preprocessor directive conditions is not negative - avoid accessing the array at negative index for else processing --- Modified: src/core/cfg.lex --- Diff: https://github.com/kamailio/kamailio/commit/8f6e826576e52270f21c22a7d94b302… Patch: https://github.com/kamailio/kamailio/commit/8f6e826576e52270f21c22a7d94b302… --- diff --git a/src/core/cfg.lex b/src/core/cfg.lex index 00fd4b5e49..53f33431df 100644 --- a/src/core/cfg.lex +++ b/src/core/cfg.lex @@ -1942,14 +1942,24 @@ static void pp_ifdef() static void pp_else() { + if(pp_sptr==0) { + LM_WARN("invalid position for preprocessor directive 'else'" + " - at %s line %d\n", (finame)?finame:"cfg", line); + return; + } pp_ifdef_stack[pp_sptr-1] ^= 1; pp_update_state(); } static void pp_endif() { - pp_sptr--; pp_ifdef_level_update(-1); + if(pp_sptr==0) { + LM_WARN("invalid position for preprocessor directive 'else'" + " - at %s line %d\n", (finame)?finame:"cfg", line); + return; + } + pp_sptr--; pp_update_state(); }