From 06ec7be557a1259611d6093a00463c42650dc71a Mon Sep 17 00:00:00 2001 From: Michael LeMay Date: Mon, 26 Jun 2006 00:24:56 -0700 Subject: [PATCH] keys: restrict contents of /proc/keys to Viewable keys Restrict /proc/keys such that only those keys to which the current task is granted View permission are presented. The documentation is also updated to reflect these changes. Signed-off-by: Michael LeMay Signed-off-by: James Morris Signed-off-by: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/Kconfig | 20 +++++++++++++------- security/keys/proc.c | 7 +++++++ 2 files changed, 20 insertions(+), 7 deletions(-) (limited to 'security') diff --git a/security/Kconfig b/security/Kconfig index 34f593410d5..67785df264e 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -22,16 +22,22 @@ config KEYS If you are unsure as to whether this is required, answer N. config KEYS_DEBUG_PROC_KEYS - bool "Enable the /proc/keys file by which all keys may be viewed" + bool "Enable the /proc/keys file by which keys may be viewed" depends on KEYS help - This option turns on support for the /proc/keys file through which - all the keys on the system can be listed. + This option turns on support for the /proc/keys file - through which + can be listed all the keys on the system that are viewable by the + reading process. - This option is a slight security risk in that it makes it possible - for anyone to see all the keys on the system. Normally the manager - pretends keys that are inaccessible to a process don't exist as far - as that process is concerned. + The only keys included in the list are those that grant View + permission to the reading process whether or not it possesses them. + Note that LSM security checks are still performed, and may further + filter out keys that the current process is not authorised to view. + + Only key attributes are listed here; key payloads are not included in + the resulting table. + + If you are unsure as to whether this is required, answer N. config SECURITY bool "Enable different security models" diff --git a/security/keys/proc.c b/security/keys/proc.c index 12b750e51fb..686a9ee0c5d 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -137,6 +137,13 @@ static int proc_keys_show(struct seq_file *m, void *v) struct timespec now; unsigned long timo; char xbuf[12]; + int rc; + + /* check whether the current task is allowed to view the key (assuming + * non-possession) */ + rc = key_task_permission(make_key_ref(key, 0), current, KEY_VIEW); + if (rc < 0) + return 0; now = current_kernel_time(); -- cgit v1.2.3-70-g09d2