Thread (21 messages) 21 messages, 6 authors, 2024-06-05

Re: [PATCH 3/6] auditsc: Replace memcpy() with __get_task_comm()

From: Paul Moore <paul@paul-moore.com>
Date: 2024-06-03 21:04:08
Also in: bpf, linux-fsdevel, linux-mm, linux-security-module, selinux

On Sat, Jun 1, 2024 at 10:38 PM Yafang Shao [off-list ref] wrote:
Using __get_task_comm() to read the task comm ensures that the name is
always NUL-terminated, regardless of the source string. This approach also
facilitates future extensions to the task comm.

Signed-off-by: Yafang Shao <redacted>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Eric Paris <eparis@redhat.com>
---
 kernel/auditsc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
Assuming you've sorted out all the problems identified earlier in the
patchset and __get_task_comm() no longer takes task_lock() this should
be okay from an audit perspective.

Acked-by: Paul Moore <paul@paul-moore.com>
quoted hunk ↗ jump to hunk
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 6f0d6fb6523f..0459a141dc86 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2730,7 +2730,7 @@ void __audit_ptrace(struct task_struct *t)
        context->target_uid = task_uid(t);
        context->target_sessionid = audit_get_sessionid(t);
        security_task_getsecid_obj(t, &context->target_sid);
-       memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
+       __get_task_comm(context->target_comm, TASK_COMM_LEN, t);
 }

 /**
@@ -2757,7 +2757,7 @@ int audit_signal_info_syscall(struct task_struct *t)
                ctx->target_uid = t_uid;
                ctx->target_sessionid = audit_get_sessionid(t);
                security_task_getsecid_obj(t, &ctx->target_sid);
-               memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
+               __get_task_comm(ctx->target_comm, TASK_COMM_LEN, t);
                return 0;
        }
@@ -2778,7 +2778,7 @@ int audit_signal_info_syscall(struct task_struct *t)
        axp->target_uid[axp->pid_count] = t_uid;
        axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
        security_task_getsecid_obj(t, &axp->target_sid[axp->pid_count]);
-       memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
+       __get_task_comm(axp->target_comm[axp->pid_count], TASK_COMM_LEN, t);
        axp->pid_count++;

        return 0;
--
2.39.1
-- 
paul-moore.com
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help