[PATCH v2 8.4/8.4] block: sed-opal: check size of shadow mbr
From: Jonas Rabenstein <hidden>
Date: 2018-03-14 06:16:44
Also in:
lkml
Subsystem:
block layer, secure encrypting device (sed) opal driver, the rest · Maintainers:
Jens Axboe, Jonathan Derrick, Linus Torvalds
Check whether the shadow mbr does fit in the provided space on the target. Also a proper firmware should handle this case and return an error we may prevent problem with crappy firmwares. Signed-off-by: Jonas Rabenstein <redacted> --- block/sed-opal.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/block/sed-opal.c b/block/sed-opal.c
index 4d93a6097ec0..8a08ae91bc25 100644
--- a/block/sed-opal.c
+++ b/block/sed-opal.c@@ -1544,6 +1544,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) u64 len; int err = 0; + /* do we fit in the available shadow mbr space? */ + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); + if (err) { + pr_debug("MBR: could not get shadow size\n"); + return err; + } + + len = response_get_u64(&dev->parsed, 4); + if (shadow->offset + shadow->size > len) { + pr_debug("MBR: does not fit in shadow (%llu vs. %llu)\n", + shadow->offset + shadow->size, len); + return -ENOSPC; + } + /* FIXME: this is the maximum we can use for IO_BUFFER_LENGTH=2048. * Instead of having constant, it would be nice to compute the * actual value depending on IO_BUFFER_LENGTH
--
2.16.1