@@ -500,34 +500,34 @@ static int apparmor_setprocattr(struct task_struct *task, char *name,
{
struct common_audit_data sa;
struct apparmor_audit_data aad = {0,};
- char *command, *args = value;
+ char *command, *largs = NULL, *args = value;
size_t arg_size;
int error;
if (size == 0)
return -EINVAL;
- /* args points to a PAGE_SIZE buffer, AppArmor requires that
- * the buffer must be null terminated or have size <= PAGE_SIZE -1
- * so that AppArmor can null terminate them
- */
- if (args[size - 1] != '\0') {
- if (size == PAGE_SIZE)
- return -EINVAL;
- args[size] = '\0';
- }
-
/* task can only write its own attributes */
if (current != task)
return -EACCES;
- args = value;
+ /* AppArmor requires that the buffer must be null terminated atm */
+ if (args[size - 1] != '\0') {
+ /* null terminate */
+ largs = args = kmalloc(size + 1, GFP_KERNEL);
+ if (!args)
+ return -ENOMEM;
+ memcpy(args, value, size);
+ args[size] = '\0';
+ }
+
+ error = -EINVAL;
args = strim(args);
command = strsep(&args, " ");
if (!args)
- return -EINVAL;
+ goto out;
args = skip_spaces(args);
if (!*args)
- return -EINVAL;
+ goto out;
arg_size = size - (args - (char *) value);
if (strcmp(name, "current") == 0) {
@@ -553,10 +553,12 @@ static int apparmor_setprocattr(struct task_struct *task, char *name,
goto fail;
} else
/* only support the "current" and "exec" process attributes */
- return -EINVAL;
+ goto fail;
if (!error)
error = size;
+out:
+ kfree(largs);
return error;
fail:
@@ -565,9 +567,9 @@ fail:
aad.profile = aa_current_profile();
aad.op = OP_SETPROCATTR;
aad.info = name;
- aad.error = -EINVAL;
+ aad.error = error = -EINVAL;
aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
- return -EINVAL;
+ goto out;
}
static int apparmor_task_setrlimit(struct task_struct *task,
Please pull. Note: it may be possible to get a local privilege escalation out of this bug. The following changes since commit ac904ae6e6f0a56be7b9a1cf66fbd50dd025fb06: Merge branch 'for-linus' of git://git.kernel.dk/linux-block (2016-07-07 15:34:09 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git for-linus Vegard Nossum (1): apparmor: fix oops, validate buffer size in apparmor_setprocattr() security/apparmor/lsm.c | 36 +++++++++++++++++++----------------- 1 files changed, 19 insertions(+), 17 deletions(-) --- commit 30a46a4647fd1df9cf52e43bf467f0d9265096ca Author: Vegard Nossum <vegard.nossum@oracle.com> Date: Thu Jul 7 13:41:11 2016 -0700 apparmor: fix oops, validate buffer size in apparmor_setprocattr() When proc_pid_attr_write() was changed to use memdup_user apparmor's (interface violating) assumption that the setprocattr buffer was always a single page was violated. The size test is not strictly speaking needed as proc_pid_attr_write() will reject anything larger, but for the sake of robustness we can keep it in. SMACK and SELinux look safe to me, but somebody else should probably have a look just in case. Based on original patch from Vegard Nossum <vegard.nossum@oracle.com> modified for the case that apparmor provides null termination. Fixes: bb646cdb12e75d82258c2f2e7746d5952d3e321a Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: John Johansen <john.johansen@canonical.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Eric Paris <eparis@parisplace.org> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: stable@kernel.org Signed-off-by: John Johansen <john.johansen@canonical.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: James Morris <james.l.morris@oracle.com> -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html