Bug 2255

Summary: ELF binfmt module calls do_brk to map PT_LOAD segments with a memsize > filesize, so discards mmap PROT flags
Product: Other Reporter: Mike Hearn (mike)
Component: ModulesAssignee: other_other
Status: REJECTED INSUFFICIENT_DATA    
Severity: normal CC: protasnb, roland
Priority: P2    
Hardware: i386   
OS: Linux   
Kernel Version: 2.6.1 Tree: Mainline
Regression: ---

Description Mike Hearn 2004-03-05 08:59:14 UTC
Line 698 of fs/binfmt_elf.c appears to contain a bug, whereby if a large non-BSS
(nobits) PT_LOAD segment is loaded set_brk is called which in turn calls do_brk,
which maps the area but discards the protection flags requested in the binary.

This bug was reported to me second-hand, so I can't be sure I got all the
details correct. Please let me know if not. This bug prevents Wine from using a
new ELF section to reserve parts of the address space that are required.

thanks -mike
Comment 1 Natalie Protasevich 2007-08-23 15:08:13 UTC
Mike,
Any update on this problem? How are new kernels work for you?
Thanks.
Comment 2 Natalie Protasevich 2008-05-02 16:00:16 UTC
Someone affiliated with Wine said that this problem has been worked around so far.
Do we need a proper fix to it?
Comment 3 Roland McGrath 2008-05-02 20:16:46 UTC
To get a useful response, the bug needs details such as the eu-readelf -l layout of a binary that reproduces the problem.