Re: [PATCH 2/2] procfs: make /proc/*/pagemap 0400

From: Andy Lutomirski
Date: Mon Dec 16 2013 - 20:52:26 EST


On Sun, Dec 15, 2013 at 10:57 AM, Djalal Harouni <tixxdz@xxxxxxxxxx> wrote:
> 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.
>

Looks good.

Acked-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>

> Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Signed-off-by: Djalal Harouni <tixxdz@xxxxxxxxxx>
> ---
> 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 e69df4b..081d055 100644
> --- a/fs/proc/base.c
> +++ b/fs/proc/base.c
> @@ -2616,7 +2616,7 @@ 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),
> @@ -2954,7 +2954,7 @@ 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),
> --
> 1.7.11.7
>



--
Andy Lutomirski
AMA Capital Management, LLC
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/