From 32ed74a4b968a4faff7aaaff557035ce5d5e70ab Mon Sep 17 00:00:00 2001 From: Djalal Harouni Date: Mon, 7 Apr 2014 15:38:38 -0700 Subject: [PATCH] procfs: make /proc/*/pagemap 0400 The /proc/*/pagemap contain sensitive information and currently its mode is 0444. Change this to 0400, so the VFS will prevent unprivileged processes from getting file descriptors on arbitrary privileged /proc/*/pagemap files. This reduces the scope of address space leaking and bypasses by protecting already running processes. Signed-off-by: Djalal Harouni Acked-by: Kees Cook Acked-by: Andy Lutomirski Cc: Eric W. Biederman Cc: Al Viro Cc: Oleg Nesterov Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/base.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index a08c92289357..8da60e768b42 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2617,7 +2617,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_PROC_PAGE_MONITOR REG("clear_refs", S_IWUSR, proc_clear_refs_operations), REG("smaps", S_IRUGO, proc_pid_smaps_operations), - REG("pagemap", S_IRUGO, proc_pagemap_operations), + REG("pagemap", S_IRUSR, proc_pagemap_operations), #endif #ifdef CONFIG_SECURITY DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), @@ -2955,7 +2955,7 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_PROC_PAGE_MONITOR REG("clear_refs", S_IWUSR, proc_clear_refs_operations), REG("smaps", S_IRUGO, proc_tid_smaps_operations), - REG("pagemap", S_IRUGO, proc_pagemap_operations), + REG("pagemap", S_IRUSR, proc_pagemap_operations), #endif #ifdef CONFIG_SECURITY DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),