From 984c609d541441660d48fc531d9041f9f14bc352 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Thu, 22 May 2014 10:44:18 +1000 Subject: [PATCH] ipcshm-document-new-limits-in-the-uapi-header-v3 Signed-off-by: Davidlohr Bueso Acked-by: Michael Kerrisk Cc: Manfred Spraul Signed-off-by: Andrew Morton --- include/uapi/linux/shm.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/shm.h b/include/uapi/linux/shm.h index 3400b6eb1fbe..1fbf24ea37fd 100644 --- a/include/uapi/linux/shm.h +++ b/include/uapi/linux/shm.h @@ -8,13 +8,13 @@ #endif /* - * SHMMNI, SHMMAX and SHMALL are the default upper limits which can be - * modified by sysctl. Both SHMMAX and SHMALL have their default values - * to the maximum limit which is as large as it can be without helping - * userspace overflow the values. There is really nothing the kernel - * can do to avoid this any further. It is therefore not advised to - * make them any larger. These limits are suitable for both 32 and - * 64-bit systems. + * SHMMNI, SHMMAX and SHMALL are default upper limits which can be + * modified by sysctl. The SHMMAX and SHMALL values have been chosen to + * be as large possible without facilitating scenarios where userspace + * causes overflows when adjusting the limits via operations of the form + * "retrieve current limit; add X; update limit". It is therefore not + * advised to make SHMMAX and SHMALL any larger. These limits are + * suitable for both 32 and 64-bit systems. */ #define SHMMIN 1 /* min shared seg size (bytes) */ #define SHMMNI 4096 /* max num of segs system wide */ -- 2.39.5