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| author | Andreas Schwab <schwab@suse.de> | 2019-10-30 10:38:36 +0100 |
|---|---|---|
| committer | Andreas Schwab <schwab@suse.de> | 2019-11-11 12:24:59 +0100 |
| commit | fc141ea78ee3d87c67b18488827fe2d89c9343e7 (patch) | |
| tree | 1279ce8cbfa3f463a1bd628a66d9e084291b73f1 | |
| parent | 2e44b10b42d68d9887ccab17b76db5d7bbae4fb6 (diff) | |
| download | glibc-fc141ea78ee3d87c67b18488827fe2d89c9343e7.tar.gz | |
Fix array bounds violation in regex matcher (bug 25149)
If the regex has more subexpressions than the number of elements allocated
in the regmatch_t array passed to regexec then proceed_next_node may
access the regmatch_t array outside its bounds.
No testcase added because even without this bug it would then crash in
pop_fail_stack which is bug 11053.
| -rw-r--r-- | posix/regexec.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/posix/regexec.c b/posix/regexec.c index 3c46ac81dd..38b6d6719a 100644 --- a/posix/regexec.c +++ b/posix/regexec.c @@ -1266,10 +1266,13 @@ proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs, if (type == OP_BACK_REF) { Idx subexp_idx = dfa->nodes[node].opr.idx + 1; - naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; + if (subexp_idx < nregs) + naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; if (fs != NULL) { - if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1) + if (subexp_idx >= nregs + || regs[subexp_idx].rm_so == -1 + || regs[subexp_idx].rm_eo == -1) return -1; else if (naccepted) { |