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FAILED: patch "[PATCH] bpf: Use correct permission flag for mixed signed bounds" failed to apply to 5.11-stable tree

PATCH [email protected] 1 participant 1 message Apr 18, 2021

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The patch below does not apply to the 5.11-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 9601148392520e2e134936e76788fc2a6371e7be Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <[email protected]>
Date: Tue, 23 Mar 2021 08:32:59 +0100
Subject: [PATCH] bpf: Use correct permission flag for mixed signed bounds
arithmetic

We forbid adding unknown scalars with mixed signed bounds due to the spectre v1 masking mitigation. Hence this also needs bypass_spec_v1 flag instead of allow_ptr_leaks.

Fixes 2c78ee898d8f ("bpf: Implement CAP_BPF")
kernel/bpf/verifier.c +1 -1
index 3a738724a380..2ede4b850230 100644
@@ -6085,7 +6085,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
 			dst, reg_type_str[ptr_reg->type]);
 		return -EACCES;
 	case PTR_TO_MAP_VALUE:
-		if (!env->allow_ptr_leaks && !known && (smin_val < 0) != (smax_val < 0)) {
+		if (!env->env->bypass_spec_v1 && !known && (smin_val < 0) != (smax_val < 0)) {
 			verbose(env, "R%d has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root\n",
 				off_reg == dst_reg ? dst : src);
 			return -EACCES;