From: Yeoreum Yun <yeoreum.yun@arm.com>
Date: Wed, 18 Jun 2025 09:29:51 +0000 (+0100)
Subject: prctl: Introduce PR_MTE_STORE_ONLY
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b1fabef37bd504f378a203fd8b9227b8fa65b193;p=thirdparty%2Fkernel%2Fstable.git

prctl: Introduce PR_MTE_STORE_ONLY

PR_MTE_STORE_ONLY is used to restrict the MTE tag check for store
opeartion only.

Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250618092957.2069907-3-yeoreum.yun@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---

diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h
index 43dec6eed559..f6fb137c407f 100644
--- a/include/uapi/linux/prctl.h
+++ b/include/uapi/linux/prctl.h
@@ -244,6 +244,8 @@ struct prctl_mm_map {
 # define PR_MTE_TAG_MASK		(0xffffUL << PR_MTE_TAG_SHIFT)
 /* Unused; kept only for source compatibility */
 # define PR_MTE_TCF_SHIFT		1
+/* MTE tag check store only */
+# define PR_MTE_STORE_ONLY		(1UL << 19)
 /* RISC-V pointer masking tag length */
 # define PR_PMLEN_SHIFT			24
 # define PR_PMLEN_MASK			(0x7fUL << PR_PMLEN_SHIFT)