From 2aa4ad626ee7f817a8f4715a47b318cfdc1714c9 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Steffen=20B=C3=A4tz?= Date: Sat, 12 Jul 2025 19:17:27 +0100 Subject: [PATCH] nvmem: imx-ocotp: fix MAC address byte length MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The commit "13bcd440f2ff nvmem: core: verify cell's raw_len" caused an extension of the "mac-address" cell from 6 to 8 bytes due to word_size of 4 bytes. This led to a required byte swap of the full buffer length, which caused truncation of the mac-address when read. Previously, the mac-address was incorrectly truncated from 70:B3:D5:14:E9:0E to 00:00:70:B3:D5:14. Fix the issue by swapping only the first 6 bytes to correctly pass the mac-address to the upper layers. Fixes: 13bcd440f2ff ("nvmem: core: verify cell's raw_len") Cc: stable@vger.kernel.org Signed-off-by: Steffen Bätz Tested-by: Alexander Stein Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20250712181729.6495-3-srini@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/nvmem/imx-ocotp-ele.c | 5 ++++- drivers/nvmem/imx-ocotp.c | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/nvmem/imx-ocotp-ele.c b/drivers/nvmem/imx-ocotp-ele.c index ca6dd71d8a2e2..7807ec0e2d18d 100644 --- a/drivers/nvmem/imx-ocotp-ele.c +++ b/drivers/nvmem/imx-ocotp-ele.c @@ -12,6 +12,7 @@ #include #include #include +#include /* ETH_ALEN */ enum fuse_type { FUSE_FSB = BIT(0), @@ -118,9 +119,11 @@ static int imx_ocotp_cell_pp(void *context, const char *id, int index, int i; /* Deal with some post processing of nvmem cell data */ - if (id && !strcmp(id, "mac-address")) + if (id && !strcmp(id, "mac-address")) { + bytes = min(bytes, ETH_ALEN); for (i = 0; i < bytes / 2; i++) swap(buf[i], buf[bytes - i - 1]); + } return 0; } diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c index 79dd4fda03295..7bf7656d4f963 100644 --- a/drivers/nvmem/imx-ocotp.c +++ b/drivers/nvmem/imx-ocotp.c @@ -23,6 +23,7 @@ #include #include #include +#include /* ETH_ALEN */ #define IMX_OCOTP_OFFSET_B0W0 0x400 /* Offset from base address of the * OTP Bank0 Word0 @@ -227,9 +228,11 @@ static int imx_ocotp_cell_pp(void *context, const char *id, int index, int i; /* Deal with some post processing of nvmem cell data */ - if (id && !strcmp(id, "mac-address")) + if (id && !strcmp(id, "mac-address")) { + bytes = min(bytes, ETH_ALEN); for (i = 0; i < bytes / 2; i++) swap(buf[i], buf[bytes - i - 1]); + } return 0; } -- 2.47.2