+ mm-simplify-min_brk-handling-in-brk.patch added to mm-new branch

+ mm-simplify-min_brk-handling-in-brk.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: mm: simplify min_brk handling in brk()
has been added to the -mm mm-new branch.  Its filename is
     mm-simplify-min_brk-handling-in-brk.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-simplify-min_brk-handling-in-brk.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

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------------------------------------------------------
From: Xuanye Liu <liuqiye2025@163.com>
Subject: mm: simplify min_brk handling in brk()
Date: Thu, 10 Jul 2025 10:58:58 +0800

Set min_brk to mm->start_brk by default, and override it with mm->end_data
only when CONFIG_COMPAT_BRK is enabled and brk_randomized is false.

This makes the logic clearer with no functional change.

Link: https://lkml.kernel.org/r/20250710025859.926355-1-liuqiye2025@163.com
Signed-off-by: Xuanye Liu <liuqiye2025@163.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

--- a/mm/mmap.c~mm-simplify-min_brk-handling-in-brk
+++ a/mm/mmap.c
@@ -127,18 +127,15 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 
 	origbrk = mm->brk;
 
+	min_brk = mm->start_brk;
 #ifdef CONFIG_COMPAT_BRK
 	/*
 	 * CONFIG_COMPAT_BRK can still be overridden by setting
 	 * randomize_va_space to 2, which will still cause mm->start_brk
 	 * to be arbitrarily shifted
 	 */
-	if (current->brk_randomized)
-		min_brk = mm->start_brk;
-	else
+	if (!current->brk_randomized)
 		min_brk = mm->end_data;
-#else
-	min_brk = mm->start_brk;
 #endif
 	if (brk < min_brk)
 		goto out;
_

Patches currently in -mm which might be from liuqiye2025@163.com are

mm-fix-spelling-issue-in-swaph.patch
mm-remove-outdated-filename-comment-in-percpu-statsc.patch
mm-simplify-min_brk-handling-in-brk.patch