From: Richard Henderson <richard.henderson@linaro.org>
Date: Tue, 2 Jan 2024 01:58:06 +0000 (+1100)
Subject: linux-user: Bound mmap_min_addr by host page size
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=78b79b2cb349114f1b3584b67f94433dd08ba05e;p=qemu.git

linux-user: Bound mmap_min_addr by host page size

Bizzarely, it is possible to set /proc/sys/vm/mmap_min_addr
to a value below the host page size.  Fix that.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Helge Deller <deller@gmx.de>
Message-Id: <20240102015808.132373-32-richard.henderson@linaro.org>
---

diff --git a/linux-user/main.c b/linux-user/main.c
index 12bb839982..551acf1661 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -901,7 +901,7 @@ int main(int argc, char **argv, char **envp)
         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
             unsigned long tmp;
             if (fscanf(fp, "%lu", &tmp) == 1 && tmp != 0) {
-                mmap_min_addr = tmp;
+                mmap_min_addr = MAX(tmp, host_page_size);
                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n",
                               mmap_min_addr);
             }