diff options
| author | Jiri Kosina <jkosina@suse.cz> | 2008-06-06 18:43:23 +0000 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2008-06-09 11:27:05 -0700 |
| commit | 921b0dbeeecd12729b49c0e9db1b70f5da1b20d3 (patch) | |
| tree | 8a7432d0bafe3ab2069012bf316a2d580b39ad4e /mm | |
| parent | 3dac273cad59097a8ab335958a7c5904f0a99d65 (diff) | |
brk: make sys_brk() honor COMPAT_BRK when computing lower bound
upstream commit: a5b4592cf77b973c29e7c9695873a26052b58951
Fix a regression introduced by
commit 4cc6028d4040f95cdb590a87db478b42b8be0508
Author: Jiri Kosina <jkosina@suse.cz>
Date: Wed Feb 6 22:39:44 2008 +0100
brk: check the lower bound properly
The check in sys_brk() on minimum value the brk might have must take
CONFIG_COMPAT_BRK setting into account. When this option is turned on
(i.e. we support ancient legacy binaries, e.g. libc5-linked stuff), the
lower bound on brk value is mm->end_code, otherwise the brk start is
allowed to be arbitrarily shifted.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mmap.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index a32d28ce31cd..96bdd73db08b 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -242,10 +242,16 @@ asmlinkage unsigned long sys_brk(unsigned long brk) unsigned long rlim, retval; unsigned long newbrk, oldbrk; struct mm_struct *mm = current->mm; + unsigned long min_brk; down_write(&mm->mmap_sem); - if (brk < mm->start_brk) +#ifdef CONFIG_COMPAT_BRK + min_brk = mm->end_code; +#else + min_brk = mm->start_brk; +#endif + if (brk < min_brk) goto out; /* |