aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJiri Kosina <jkosina@suse.cz>2008-06-05 22:46:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-06-06 11:29:09 -0700
commita5b4592cf77b973c29e7c9695873a26052b58951 (patch)
tree9f2af3014d5d41ddc22d7aa2793b871ee15297d8
parent33dda515a1995dfb3b6b57d7ace9b3ee9d449c11 (diff)
brk: make sys_brk() honor COMPAT_BRK when computing lower bound
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>
-rw-r--r--mm/mmap.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index 669499e7c2f..3354fdd83d4 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -245,10 +245,16 @@ 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;
/*