path: root/fs
diff options
authorKees Cook <kees.cook@canonical.com>2010-02-03 15:36:43 -0800
committerJames Morris <jmorris@namei.org>2010-02-04 14:20:12 +1100
commit002345925e6c45861f60db6f4fc6236713fd8847 (patch)
treed7849eafe1755116597166bbebf43e2bee86cb76 /fs
parent0719aaf5ead7555b7b7a4a080ebf2826a871384e (diff)
syslog: distinguish between /proc/kmsg and syscalls
This allows the LSM to distinguish between syslog functions originating from /proc/kmsg access and direct syscalls. By default, the commoncaps will now no longer require CAP_SYS_ADMIN to read an opened /proc/kmsg file descriptor. For example the kernel syslog reader can now drop privileges after opening /proc/kmsg, instead of staying privileged with CAP_SYS_ADMIN. MAC systems that implement security_syslog have unchanged behavior. Signed-off-by: Kees Cook <kees.cook@canonical.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'fs')
1 files changed, 7 insertions, 7 deletions
diff --git a/fs/proc/kmsg.c b/fs/proc/kmsg.c
index 7ca78346d3f0..6a3d843a1088 100644
--- a/fs/proc/kmsg.c
+++ b/fs/proc/kmsg.c
@@ -12,37 +12,37 @@
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/fs.h>
+#include <linux/syslog.h>
#include <asm/uaccess.h>
#include <asm/io.h>
extern wait_queue_head_t log_wait;
-extern int do_syslog(int type, char __user *bug, int count);
static int kmsg_open(struct inode * inode, struct file * file)
- return do_syslog(1,NULL,0);
+ return do_syslog(1, NULL, 0, SYSLOG_FROM_FILE);
static int kmsg_release(struct inode * inode, struct file * file)
- (void) do_syslog(0,NULL,0);
+ (void) do_syslog(0, NULL, 0, SYSLOG_FROM_FILE);
return 0;
static ssize_t kmsg_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
- if ((file->f_flags & O_NONBLOCK) && !do_syslog(9, NULL, 0))
+ if ((file->f_flags & O_NONBLOCK) &&
+ !do_syslog(9, NULL, 0, SYSLOG_FROM_FILE))
return -EAGAIN;
- return do_syslog(2, buf, count);
+ return do_syslog(2, buf, count, SYSLOG_FROM_FILE);
static unsigned int kmsg_poll(struct file *file, poll_table *wait)
poll_wait(file, &log_wait, wait);
- if (do_syslog(9, NULL, 0))
+ if (do_syslog(9, NULL, 0, SYSLOG_FROM_FILE))
return 0;

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