Patch "bpf: introduce in_sleepable() helper" has been added to the 6.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    bpf: introduce in_sleepable() helper

to the 6.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     bpf-introduce-in_sleepable-helper.patch
and it can be found in the queue-6.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 52f440367cd83e89dfbaffacc620b302f4af9e52
Author: Benjamin Tissoires <bentiss@xxxxxxxxxx>
Date:   Wed Feb 21 17:25:18 2024 +0100

    bpf: introduce in_sleepable() helper
    
    [ Upstream commit dfe6625df48ec54c6dc9b86d361f26962d09de88 ]
    
    No code change, but it'll allow to have only one place to change
    everything when we add in_sleepable in cur_state.
    
    Signed-off-by: Benjamin Tissoires <bentiss@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-2-1fb378ca6301@xxxxxxxxxx
    Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
    Stable-dep-of: 1a80dbcb2dba ("bpf: support deferring bpf_link dealloc to after RCU grace period")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 19e575e6b7fe0..a3cfe6f458d3b 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5211,6 +5211,11 @@ static int map_kptr_match_type(struct bpf_verifier_env *env,
 	return -EINVAL;
 }
 
+static bool in_sleepable(struct bpf_verifier_env *env)
+{
+	return env->prog->aux->sleepable;
+}
+
 /* The non-sleepable programs and sleepable programs with explicit bpf_rcu_read_lock()
  * can dereference RCU protected pointers and result is PTR_TRUSTED.
  */
@@ -5218,7 +5223,7 @@ static bool in_rcu_cs(struct bpf_verifier_env *env)
 {
 	return env->cur_state->active_rcu_lock ||
 	       env->cur_state->active_lock.ptr ||
-	       !env->prog->aux->sleepable;
+	       !in_sleepable(env);
 }
 
 /* Once GCC supports btf_type_tag the following mechanism will be replaced with tag check */
@@ -10099,7 +10104,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn
 		return -EINVAL;
 	}
 
-	if (!env->prog->aux->sleepable && fn->might_sleep) {
+	if (!in_sleepable(env) && fn->might_sleep) {
 		verbose(env, "helper call might sleep in a non-sleepable prog\n");
 		return -EINVAL;
 	}
@@ -10129,7 +10134,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn
 			return -EINVAL;
 		}
 
-		if (env->prog->aux->sleepable && is_storage_get_function(func_id))
+		if (in_sleepable(env) && is_storage_get_function(func_id))
 			env->insn_aux_data[insn_idx].storage_get_func_atomic = true;
 	}
 
@@ -11488,7 +11493,7 @@ static bool check_css_task_iter_allowlist(struct bpf_verifier_env *env)
 			return true;
 		fallthrough;
 	default:
-		return env->prog->aux->sleepable;
+		return in_sleepable(env);
 	}
 }
 
@@ -12009,7 +12014,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
 	}
 
 	sleepable = is_kfunc_sleepable(&meta);
-	if (sleepable && !env->prog->aux->sleepable) {
+	if (sleepable && !in_sleepable(env)) {
 		verbose(env, "program must be sleepable to call sleepable kfunc %s\n", func_name);
 		return -EACCES;
 	}
@@ -19575,7 +19580,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
 		}
 
 		if (is_storage_get_function(insn->imm)) {
-			if (!env->prog->aux->sleepable ||
+			if (!in_sleepable(env) ||
 			    env->insn_aux_data[i + delta].storage_get_func_atomic)
 				insn_buf[0] = BPF_MOV64_IMM(BPF_REG_5, (__force __s32)GFP_ATOMIC);
 			else