Bug 113421
| Summary: | peek_token() uses uninitialized array element in posix/bug-regex20 | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | John Reiser <jreiser> |
| Component: | glibc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Brian Brock <bbrock> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 1 | CC: | drepper |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i386 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2004-09-28 09:44:37 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Assume fixed in current release. |
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.1) Gecko/20031114 Description of problem: Running testcase posix/bug-regex20, the code uses an uninitialized array element. The valgrind/memcheck complaint is ----- ==22450== Conditional jump or move depends on uninitialised value(s) ==22450== at 0xD88A5D: peek_token (in /lib/i686/libc-2.3.2.so) ==22450== by 0xD88EC8: parse_expression (in /lib/i686/libc-2.3.2.so) ==22450== by 0xD88D8A: parse_branch (in /lib/i686/libc-2.3.2.so) ==22450== by 0xD88BDD: parse_reg_exp (in /lib/i686/libc-2.3.2.so) ----- The Insure++ complaint (in no-recompile mode) is ----- [regcomp.c:765] (Thread 0) **READ_UNINIT_MEM(read)** >> #ifdef DEBUG Reading uninitialized memory. Pointer : 0x4022001c In block: 0x4021ffe8 thru 0x4022001f (56 bytes) block allocated at regex_internal.c, 155 re_string_realloc_buffers() regex_internal.c, 155 re_string_construct() regex_internal.c, 94 re_compile_internal() regcomp.c, 770 __re_compile_pattern() regcomp.c, 247 main() bug-regex20.c, 247 Stack trace where the error occurred: peek_token() regcomp.c, 765 parse_expression() regcomp.c, 1613 parse_branch() regcomp.c, 2061 parse_reg_exp() regcomp.c, 2006 parse() regcomp.c, 1970 re_compile_internal() regcomp.c, 785 __re_compile_pattern() regcomp.c, 247 main() bug-regex20.c, 247 ----- Version-Release number of selected component (if applicable): glibc-2.3.2-101.4 How reproducible: Always Steps to Reproduce: 1. Run internal testcase posix/bug-regex20 under a memory access checker. Or: run under gdb, break at the 34-th call to re_realloc() within re_string_realloc_buffers() at regex_internal.c:154, set a read-and-write watchpoint on the 13th 4-byte element of the 14-element array, and notice that the first access is a read ['cmpl' on i386] instead of a write. [See Additional Information below.] Actual Results: Complaints about use of uninit value, as noted in Description. Expected Results: No use of uninit value. Additional info: The relevant raw_mbs is "^x\\\\y\\{6\\}z\\+" which is a 13-byte string ----- ^ x \ \ y \ { 6 \ } z \ + ----- The uninit element is the last element of a 14-element array allocated by re_string_realloc_buffers() on the 34-th time at regex_internal.c:154 calling re_realloc().