FAILED: patch "[PATCH] binder: use cred instead of task for getsecid" failed to apply to 5.10-stable tree
Subsystems (3)
[email protected]
maintainerThe patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4d5b5539742d2554591751b4248b0204d20dcc9d Mon Sep 17 00:00:00 2001
From: Todd Kjos <[email protected]>
Date: Tue, 12 Oct 2021 09:56:14 -0700
Subject: [PATCH] binder: use cred instead of task for getsecid
Use the 'struct cred' saved at binder_open() to lookup the security ID via security_cred_getsecid(). This ensures that the security context that opened binder is the one used to generate the secctx.
Cc [email protected] # 5.4+
Fixes ec74136ded79 ("binder: create node flag to request sender's security context")
Signed-off-by Todd Kjos <[email protected]>
Suggested-by Stephen Smalley <[email protected]>
Reported-by kernel test robot <[email protected]>
Acked-by Casey Schaufler <[email protected]>
Signed-off-by Paul Moore <[email protected]>
drivers/android/binder.c +1 -10
@@ -2713,16 +2713,7 @@ static void binder_transaction(struct binder_proc *proc,u32 secid;size_t added_size; -/* -* Arguably this should be the task's subjective LSM secid but -* we can't reliably access the subjective creds of a task -* other than our own so we must use the objective creds, which -* are safe to access. The downside is that if a task is -* temporarily overriding it's creds it will not be reflected -* here; however, it isn't clear that binder would handle that -* case well anyway. -*/ -security_task_getsecid_obj (proc->tsk, &secid); +security_cred_getsecid (proc->cred, &secid); ret =security_secid_to_secctx (secid, &secctx, &secctx_sz);if (ret) { return_error =BR_FAILED_REPLY ;
include/linux/security.h +5 -0
@@ -1041,6 +1041,11 @@ static inline void security_transfer_creds(struct cred *new, { } +static inline void security_cred_getsecid (const struct cred *c,u32 *secid) +{ + *secid =0 ; +} +static inline int security_kernel_act_as (struct cred *cred,u32 secid) {return 0 ;