Bug 160889
| Summary: | mmap(,,PROT_NONE,MAP_FIXED,,) gives PROT_EXEC | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | John Reiser <jreiser> |
| Component: | kernel | Assignee: | Ingo Molnar <mingo> |
| Status: | CLOSED NOTABUG | QA Contact: | Brian Brock <bbrock> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 4 | CC: | davej, wtogami |
| 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: | 2005-09-15 19:47:04 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: | |||
[This comment has been added as a mass update for all FC4 kernel bugs. If you have migrated this bug from an FC3 bug today, ignore this comment.] Please retest your problem with todays 2.6.12-1.1398_FC4 update. If your problem involved being unable to boot, or some hardware not being detected correctly, please make sure your /etc/modprobe.conf is correct *BEFORE* installing any kernel updates. If in doubt, you can recreate this file using.. mv /etc/sysconfig/hwconf /etc/sysconfig/hwconf.bak mv /etc/modprobe.conf /etc/modprobe.conf.bak kudzu Thank you. The problem still occurs in kernel-2.6.12-1.1398_FC4 on i686. we started marking all truly executable mappings as "x" in /proc/<pid>/maps to reflect reality on x86. On NX-capable kernel, running a PAE kernel, you should be getting ---p. with exec-shield, even on x86, areas marked at non-x are truly non-executable. On the stock Linux kernel, all mappings are executable on x86. |
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050524 Fedora/1.0.4-4 Firefox/1.0.4 Description of problem: The combination PROT_NONE with MAP_FIXED as arguments to syscall mmap() results in PROT_EXEC (--xp) instead of PROT_NONE (---p). Reproducible testcase (using glibc-2.3.5-10): ----- #include <sys/mman.h> #include <stdio.h> #include <stdlib.h> main() { char buf[80]; char *p=mmap(0x1000, 4096, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED, 0, 0); sprintf(buf, "echo PROT_NONE=0x%x; cat /proc/%d/maps", PROT_NONE, getpid()); popen(buf, "w"); sleep(3); return 0; } ----- Version-Release number of selected component (if applicable): kernel-2.6.11-1.1369_FC4 How reproducible: Always Steps to Reproduce: 1. Compile and execute the program given in the Description. 2. 3. Actual Results: The first line of the /proc/PID/maps is 00001000-00002000 --xp 00001000 00:00 0 [Note the actual "--xp" instead of the desired "---p".] Expected Results: The first line of the /proc/PID/maps should be 00001000-00002000 ---p 00001000 00:00 0 [Note the desired "---p" instead of the actual "--xp".] Additional info: