Bug 292981
| Summary: | Debugee send TWO sigtrap to itslf when execute misc/script | ||||||||
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| Product: | Red Hat Enterprise Linux 5 | Reporter: | Eric Lin <eric.lin> | ||||||
| Component: | ia32el | Assignee: | Petr Machata <pmachata> | ||||||
| Status: | CLOSED WONTFIX | QA Contact: | |||||||
| Severity: | high | Docs Contact: | |||||||
| Priority: | medium | ||||||||
| Version: | 5.0 | CC: | anton.fang, eric.lin, law, luyu, mnewsome, yihua.jin | ||||||
| Target Milestone: | --- | ||||||||
| Target Release: | --- | ||||||||
| Hardware: | ia64 | ||||||||
| OS: | Linux | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | Environment: | ||||||||
| Last Closed: | 2013-03-20 15:35:21 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: | |||||||||
| Attachments: |
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Created attachment 197221 [details]
A case compialed natively can reproduce the problem
Created attachment 197281 [details]
the entire test suite to reproduse the problem, including src, binary, script
execute ./ptrace_exec64 and will get a assertion.
There are no plans to issue further updates to the ia32el package in Red Hat Enterprise Linux 5. Therefore, this bug is being closed as WONTFIX. |
Description of problem: In RHEL5, if a debuggee execute a misc/script binary, SIGTRAP will be sent twice to itself, so that debugger will receive TWO SIGCHLD. After investigate, the problem is that the notify procedure (fuction "tracehook_report_exec" ) is put in function "search_binary_hanlder", rather than in "load_elf_binary" as in RHEL4. SO the logic of execute a misc/script binary will belike this: do_execve ( ) |___ search_binary_handler ( ) |___load_misc_bianry ( ) | |___search_bianry_handler ( ) | |___ load_elf_binary ( ) | |___ tracehook_report_exec ( ) |___ tracehook_report_exec( ) obviously, "tracehook_report_exec" will be called twice, which send TWO SIGTRAP. ia32el depend on load_misc_bianry to simulate 32-bit binary, so if use 32- bit gdb to debug 32-bit app on ia32el, gdb will get a extra SIGCHLD. For simply reporduce the problem, attached is a 64-bit case using ptrace to attach a child while execute a script and check the status.Normally, parent should receive ONE sigchld when child(debugee) call "execve", but in this case, it receive TWICE since child execute a script. Version-Release number of selected component (if applicable): How reproducible: Steps to Reproduce: 1.compile the attached file natively: make ptrace_exec64 2.Run : ./ptrace_exec64 3.Get assert failure Actual results: Expected results: Additional info: