lkml.org 
[lkml]   [2008]   [Feb]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[Patch] Elf loader crash while zero-filling .bss
I've finally found a solution for the crash in load_binary_elf I
reported last week:

http://lkml.org/lkml/2008/1/30/171

The attached patch solves my problem, but please test it yourself...

set_brk(start, end) allocs just page aligned regions (by "colapsing"
both extremes to the start of the page in which they lay)... That
means than even if both pointers are not equal there are still some
chances that set_brk has allocated no space at all because
ELF_PAGEALIGN(elf_bss) != ELF_PAGEALIGN(elf_brk).

So the condition was not correct.


--- linux-2.6.22.10.orig/fs/binfmt_elf.c 2008-02-11 18:58:29.000000000 +0100
+++ linux-2.6.22.10.hacked/fs/binfmt_elf.c 2008-02-11 16:09:41.000000000 +0100
@@ -939,3 +939,3 @@ static int load_elf_binary(struct linux_
}
- if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
+ if (likely(ELF_PAGEALIGN(elf_bss) != ELF_PAGEALIGN(elf_brk)) &&
unlikely(padzero(elf_bss))) {
send_sig(SIGSEGV, current, 0);

\
 
 \ /
  Last update: 2008-02-11 19:31    [W:0.092 / U:0.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site