From: Zhihao Cheng chengzhihao1@huawei.com
commit 1e020e1b96afdecd20680b5b5be2a6ffc3d27628 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -657,12 +657,6 @@ 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); @@ -680,6 +674,21 @@ 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);