diff -ur linux-2.6.10/arch/mips/kernel/irixelf.c linux-2.6.10.plasmaroo/arch/mips/kernel/irixelf.c
--- linux-2.6.10/arch/mips/kernel/irixelf.c	2004-12-24 21:35:50.000000000 +0000
+++ linux-2.6.10.plasmaroo/arch/mips/kernel/irixelf.c	2005-01-07 15:36:00.383356800 +0000
@@ -127,7 +127,7 @@
 	end = PAGE_ALIGN(end);
 	if (end <= start)
 		return;
-	do_brk(start, end - start);
+	do_brk_locked(start, end - start);
 }
 
 
@@ -375,7 +375,7 @@
 
 	/* Map the last of the bss segment */
 	if (last_bss > len) {
-		do_brk(len, (last_bss - len));
+		do_brk_locked(len, (last_bss - len));
 	}
 	kfree(elf_phdata);
 
@@ -562,7 +562,7 @@
 	unsigned long v;
 	struct prda *pp;
 
-	v =  do_brk (PRDA_ADDRESS, PAGE_SIZE);
+	v =  do_brk_locked (PRDA_ADDRESS, PAGE_SIZE);
 
 	if (v < 0)
 		return;
@@ -853,7 +853,7 @@
 	len = (elf_phdata->p_filesz + elf_phdata->p_vaddr+ 0xfff) & 0xfffff000;
 	bss = elf_phdata->p_memsz + elf_phdata->p_vaddr;
 	if (bss > len)
-	  do_brk(len, bss-len);
+	  do_brk_locked(len, bss-len);
 	kfree(elf_phdata);
 	return 0;
 }
diff -ur linux-2.6.10/arch/sparc64/kernel/binfmt_aout32.c linux-2.6.10.plasmaroo/arch/sparc64/kernel/binfmt_aout32.c
--- linux-2.6.10/arch/sparc64/kernel/binfmt_aout32.c	2004-12-24 21:34:45.000000000 +0000
+++ linux-2.6.10.plasmaroo/arch/sparc64/kernel/binfmt_aout32.c	2005-01-07 15:36:00.432349352 +0000
@@ -49,7 +49,7 @@
 	end = PAGE_ALIGN(end);
 	if (end <= start)
 		return;
-	do_brk(start, end - start);
+	do_brk_locked(start, end - start);
 }
 
 /*
@@ -246,10 +246,10 @@
 	if (N_MAGIC(ex) == NMAGIC) {
 		loff_t pos = fd_offset;
 		/* Fuck me plenty... */
-		error = do_brk(N_TXTADDR(ex), ex.a_text);
+		error = do_brk_locked(N_TXTADDR(ex), ex.a_text);
 		bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex),
 			  ex.a_text, &pos);
-		error = do_brk(N_DATADDR(ex), ex.a_data);
+		error = do_brk_locked(N_DATADDR(ex), ex.a_data);
 		bprm->file->f_op->read(bprm->file, (char __user *)N_DATADDR(ex),
 			  ex.a_data, &pos);
 		goto beyond_if;
@@ -257,7 +257,7 @@
 
 	if (N_MAGIC(ex) == OMAGIC) {
 		loff_t pos = fd_offset;
-		do_brk(N_TXTADDR(ex) & PAGE_MASK,
+		do_brk_locked(N_TXTADDR(ex) & PAGE_MASK,
 			ex.a_text+ex.a_data + PAGE_SIZE - 1);
 		bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex),
 			  ex.a_text+ex.a_data, &pos);
@@ -272,7 +272,7 @@
 
 		if (!bprm->file->f_op->mmap) {
 			loff_t pos = fd_offset;
-			do_brk(0, ex.a_text+ex.a_data);
+			do_brk_locked(0, ex.a_text+ex.a_data);
 			bprm->file->f_op->read(bprm->file,
 				  (char __user *)N_TXTADDR(ex),
 				  ex.a_text+ex.a_data, &pos);
@@ -389,7 +389,7 @@
 	len = PAGE_ALIGN(ex.a_text + ex.a_data);
 	bss = ex.a_text + ex.a_data + ex.a_bss;
 	if (bss > len) {
-		error = do_brk(start_addr + len, bss - len);
+		error = do_brk_locked(start_addr + len, bss - len);
 		retval = error;
 		if (error != start_addr + len)
 			goto out;
diff -Nur linux-2.6.10/arch/x86_64/ia32/ia32_aout.c linux-2.6.10.plasmaroo/arch/x86_64/ia32/ia32_aout.c
--- linux-2.6.10/arch/x86_64/ia32/ia32_aout.c	2005-01-03 16:17:04.000000000 -0200
+++ linux-2.6.10.plasmaroo/arch/x86_64/ia32/ia32_aout.c	2005-01-03 16:46:53.846823360 -0200
@@ -115,7 +115,7 @@
 	end = PAGE_ALIGN(end);
 	if (end <= start)
 		return;
-	do_brk(start, end - start);
+	do_brk_locked(start, end - start);
 }
 
 #if CORE_DUMP
@@ -325,7 +325,7 @@
 		pos = 32;
 		map_size = ex.a_text+ex.a_data;
 
-		error = do_brk(text_addr & PAGE_MASK, map_size);
+		error = do_brk_locked(text_addr & PAGE_MASK, map_size);
 		if (error != (text_addr & PAGE_MASK)) {
 			send_sig(SIGKILL, current, 0);
 			return error;
@@ -361,7 +361,7 @@
 
 		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
 			loff_t pos = fd_offset;
-			do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
+			do_brk_locked(N_TXTADDR(ex), ex.a_text+ex.a_data);
 			bprm->file->f_op->read(bprm->file,(char *)N_TXTADDR(ex),
 					ex.a_text+ex.a_data, &pos);
 			flush_icache_range((unsigned long) N_TXTADDR(ex),
@@ -470,7 +470,7 @@
 		}
 #endif
 
-		do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
+		do_brk_locked(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 		
 		file->f_op->read(file, (char *)start_addr,
 			ex.a_text + ex.a_data, &pos);
@@ -494,7 +494,7 @@
 	len = PAGE_ALIGN(ex.a_text + ex.a_data);
 	bss = ex.a_text + ex.a_data + ex.a_bss;
 	if (bss > len) {
-		error = do_brk(start_addr + len, bss - len);
+		error = do_brk_locked(start_addr + len, bss - len);
 		retval = error;
 		if (error != start_addr + len)
 			goto out;
diff -ur linux-2.6.10/fs/binfmt_aout.c linux-2.6.10.plasmaroo/fs/binfmt_aout.c
--- linux-2.6.10/fs/binfmt_aout.c	2004-12-24 21:35:50.000000000 +0000
+++ linux-2.6.10.plasmaroo/fs/binfmt_aout.c	2005-01-07 15:36:00.000000000 +0000
@@ -50,7 +50,7 @@
 	start = PAGE_ALIGN(start);
 	end = PAGE_ALIGN(end);
 	if (end > start) {
-		unsigned long addr = do_brk(start, end - start);
+		unsigned long addr = do_brk_locked(start, end - start);
 		if (BAD_ADDR(addr))
 			return addr;
 	}
@@ -323,10 +323,10 @@
 		loff_t pos = fd_offset;
 		/* Fuck me plenty... */
 		/* <AOL></AOL> */
-		error = do_brk(N_TXTADDR(ex), ex.a_text);
+		error = do_brk_locked(N_TXTADDR(ex), ex.a_text);
 		bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),
 			  ex.a_text, &pos);
-		error = do_brk(N_DATADDR(ex), ex.a_data);
+		error = do_brk_locked(N_DATADDR(ex), ex.a_data);
 		bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),
 			  ex.a_data, &pos);
 		goto beyond_if;
@@ -347,7 +347,7 @@
 		map_size = ex.a_text+ex.a_data;
 #endif
 
-		error = do_brk(text_addr & PAGE_MASK, map_size);
+		error = do_brk_locked(text_addr & PAGE_MASK, map_size);
 		if (error != (text_addr & PAGE_MASK)) {
 			send_sig(SIGKILL, current, 0);
 			return error;
@@ -382,7 +382,7 @@
 
 		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
 			loff_t pos = fd_offset;
-			do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
+			do_brk_locked(N_TXTADDR(ex), ex.a_text+ex.a_data);
 			bprm->file->f_op->read(bprm->file,
 					(char __user *)N_TXTADDR(ex),
 					ex.a_text+ex.a_data, &pos);
@@ -488,7 +488,7 @@
 			error_time = jiffies;
 		}
 
-		do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
+		do_brk_locked(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 		
 		file->f_op->read(file, (char __user *)start_addr,
 			ex.a_text + ex.a_data, &pos);
@@ -512,7 +512,7 @@
 	len = PAGE_ALIGN(ex.a_text + ex.a_data);
 	bss = ex.a_text + ex.a_data + ex.a_bss;
 	if (bss > len) {
-		error = do_brk(start_addr + len, bss - len);
+		error = do_brk_locked(start_addr + len, bss - len);
 		retval = error;
 		if (error != start_addr + len)
 			goto out;
diff -ur linux-2.6.10/fs/binfmt_elf.c linux-2.6.10.plasmaroo/fs/binfmt_elf.c
--- linux-2.6.10/fs/binfmt_elf.c	2004-12-24 21:34:33.000000000 +0000
+++ linux-2.6.10.plasmaroo/fs/binfmt_elf.c	2005-01-07 15:36:00.000000000 +0000
@@ -88,7 +88,7 @@
 	start = ELF_PAGEALIGN(start);
 	end = ELF_PAGEALIGN(end);
 	if (end > start) {
-		unsigned long addr = do_brk(start, end - start);
+		unsigned long addr = do_brk_locked(start, end - start);
 		if (BAD_ADDR(addr))
 			return addr;
 	}
@@ -408,7 +408,7 @@
 
 	/* Map the last of the bss segment */
 	if (last_bss > elf_bss) {
-		error = do_brk(elf_bss, last_bss - elf_bss);
+		error = do_brk_locked(elf_bss, last_bss - elf_bss);
 		if (BAD_ADDR(error))
 			goto out_close;
 	}
@@ -448,7 +448,7 @@
 		goto out;
 	}
 
-	do_brk(0, text_data);
+	do_brk_locked(0, text_data);
 	if (!interpreter->f_op || !interpreter->f_op->read)
 		goto out;
 	if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0)
@@ -456,7 +456,7 @@
 	flush_icache_range((unsigned long)addr,
 	                   (unsigned long)addr + text_data);
 
-	do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
+	do_brk_locked(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
 		interp_ex->a_bss);
 	elf_entry = interp_ex->a_entry;
 
@@ -1025,7 +1025,7 @@
 	len = ELF_PAGESTART(elf_phdata->p_filesz + elf_phdata->p_vaddr + ELF_MIN_ALIGN - 1);
 	bss = elf_phdata->p_memsz + elf_phdata->p_vaddr;
 	if (bss > len)
-		do_brk(len, bss - len);
+		do_brk_locked(len, bss - len);
 	error = 0;
 
 out_free_ph:
diff -ur linux-2.6.10/include/linux/mm.h linux-2.6.10.plasmaroo/include/linux/mm.h
--- linux-2.6.10/include/linux/mm.h	2004-12-24 21:33:50.000000000 +0000
+++ linux-2.6.10.plasmaroo/include/linux/mm.h	2005-01-07 15:36:00.000000000 +0000
@@ -704,6 +704,7 @@
 extern int do_munmap(struct mm_struct *, unsigned long, size_t);
 
 extern unsigned long do_brk(unsigned long, unsigned long);
+extern unsigned long do_brk_locked(unsigned long, unsigned long);
 
 /* filemap.c */
 extern unsigned long page_unuse(struct page *);
diff -ur linux-2.6.10/mm/mmap.c linux-2.6.10.plasmaroo/mm/mmap.c
--- linux-2.6.10/mm/mmap.c	2004-12-24 21:35:00.000000000 +0000
+++ linux-2.6.10.plasmaroo/mm/mmap.c	2005-01-07 15:36:04.000000000 +0000
@@ -1826,6 +1826,20 @@
 
 EXPORT_SYMBOL(do_brk);
 
+/* locking version of do_brk. */
+unsigned long do_brk_locked(unsigned long addr, unsigned long len)
+{
+	unsigned long ret;
+
+	down_write(&current->mm->mmap_sem);
+	ret = do_brk(addr, len);
+	up_write(&current->mm->mmap_sem);
+
+	return ret;
+}
+
+EXPORT_SYMBOL(do_brk_locked);
+
 /* Release all mmaps. */
 void exit_mmap(struct mm_struct *mm)
 {
@@ -1952,3 +1966,4 @@
 	}
 	return new_vma;
 }
+
diff -ur linux-2.6.10/mm/nommu.c linux-2.6.10.plasmaroo/mm/nommu.c
--- linux-2.6.10/mm/nommu.c	2004-12-24 21:35:25.000000000 +0000
+++ linux-2.6.10.plasmaroo/mm/nommu.c	2005-01-07 15:30:24.000000000 +0000
@@ -557,6 +557,11 @@
 	return -ENOMEM;
 }
 
+unsigned long do_brk_locked(unsigned long addr, unsigned long len)
+{
+	return -ENOMEM;
+}
+
 struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr)
 {
 	return NULL;