--- /dev/null
+From 1e020e1b96afdecd20680b5b5be2a6ffc3d27628 Mon Sep 17 00:00:00 2001
+From: Zhihao Cheng <chengzhihao1@huawei.com>
+Date: Mon, 6 Mar 2023 09:33:08 +0800
+Subject: [PATCH] ubi: Fix failure attaching when vid_hdr offset equals to
+ (sub)page size
+
+Following process will make ubi attaching failed since commit
+1b42b1a36fc946 ("ubi: ensure that VID header offset ... size"):
+
+ID="0xec,0xa1,0x00,0x15" # 128M 128KB 2KB
+modprobe nandsim id_bytes=$ID
+flash_eraseall /dev/mtd0
+modprobe ubi mtd="0,2048" # set vid_hdr offset as 2048 (one page)
+(dmesg):
+ ubi0 error: ubi_attach_mtd_dev [ubi]: VID header offset 2048 too large.
+ UBI error: cannot attach mtd0
+ UBI error: cannot initialize UBI, error -22
+
+Rework original solution, the key point is making sure
+'vid_hdr_shift + UBI_VID_HDR_SIZE < ubi->vid_hdr_alsize',
+so we should check vid_hdr_shift rather not vid_hdr_offset.
+Then, ubi still support (sub)page aligined VID header offset.
+
+Fixes: 1b42b1a36fc946 ("ubi: ensure that VID header offset ... size")
+Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
+Tested-by: Nicolas Schichan <nschichan@freebox.fr>
+Tested-by: Miquel Raynal <miquel.raynal@bootlin.com> # v5.10, v4.19
+Signed-off-by: Richard Weinberger <richard@nod.at>
+---
+ drivers/mtd/ubi/build.c | 21 +++++++++++++++------
+ 1 file changed, 15 insertions(+), 6 deletions(-)
+
+--- a/drivers/mtd/ubi/build.c
++++ b/drivers/mtd/ubi/build.c
+@@ -665,12 +665,6 @@ static int io_init(struct ubi_device *ub
+ ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
+ ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
+
+- if (ubi->vid_hdr_offset && ((ubi->vid_hdr_offset + UBI_VID_HDR_SIZE) >
+- ubi->vid_hdr_alsize)) {
+- ubi_err(ubi, "VID header offset %d too large.", ubi->vid_hdr_offset);
+- return -EINVAL;
+- }
+-
+ dbg_gen("min_io_size %d", ubi->min_io_size);
+ dbg_gen("max_write_size %d", ubi->max_write_size);
+ dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
+@@ -688,6 +682,21 @@ static int io_init(struct ubi_device *ub
+ ubi->vid_hdr_aloffset;
+ }
+
++ /*
++ * Memory allocation for VID header is ubi->vid_hdr_alsize
++ * which is described in comments in io.c.
++ * Make sure VID header shift + UBI_VID_HDR_SIZE not exceeds
++ * ubi->vid_hdr_alsize, so that all vid header operations
++ * won't access memory out of bounds.
++ */
++ if ((ubi->vid_hdr_shift + UBI_VID_HDR_SIZE) > ubi->vid_hdr_alsize) {
++ ubi_err(ubi, "Invalid VID header offset %d, VID header shift(%d)"
++ " + VID header size(%zu) > VID header aligned size(%d).",
++ ubi->vid_hdr_offset, ubi->vid_hdr_shift,
++ UBI_VID_HDR_SIZE, ubi->vid_hdr_alsize);
++ return -EINVAL;
++ }
++
+ /* Similar for the data offset */
+ ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
+ ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);