diff mbox series

[v3,31/33] linux-user: Bound mmap_min_addr by host page size

Message ID 20240102015808.132373-32-richard.henderson@linaro.org
State Superseded
Headers show
Series linux-user: Improve host and guest page size handling | expand

Commit Message

Richard Henderson Jan. 2, 2024, 1:58 a.m. UTC 
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>
---
 linux-user/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Philippe Mathieu-Daudé Jan. 3, 2024, 3:32 p.m. UTC | #1 
On 2/1/24 02:58, Richard Henderson wrote:
> 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>
> ---
>   linux-user/main.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Ilya Leoshkevich Jan. 30, 2024, 1:48 p.m. UTC | #2 
On Tue, Jan 02, 2024 at 12:58:06PM +1100, Richard Henderson wrote:
> 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>
> ---
>  linux-user/main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
diff mbox series

Patch

diff --git a/linux-user/main.c b/linux-user/main.c
index d00a0d7d1f..d5f3fa26c0 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -904,7 +904,7 @@  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);
             }