libata: zpodd: Fix small read overflow in zpodd_get_mech_type()
Jeffrin reported a KASAN issue:
BUG: KASAN: global-out-of-bounds in ata_exec_internal_sg+0x50f/0xc70
Read of size 16 at addr ffffffff91f41f80 by task scsi_eh_1/149
...
The buggy address belongs to the variable:
cdb.48319+0x0/0x40
Much like commit 18c9a99bce2a ("libata: zpodd: small read overflow in
eject_tray()"), this fixes a cdb[] buffer length, this time in
zpodd_get_mech_type():
We read from the cdb[] buffer in ata_exec_internal_sg(). It has to be
ATAPI_CDB_LEN (16) bytes long, but this buffer is only 12 bytes.
Reported-by: Jeffrin Jose T <[email protected]>
Fixes: afe759511808c ("libata: identify and init ZPODD devices")
Link: https://lore.kernel.org/lkml/201907181423.E808958@keescook/
Tested-by: Jeffrin Jose T <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c
index 173e6f2..eefda51 100644
--- a/drivers/ata/libata-zpodd.c
+++ b/drivers/ata/libata-zpodd.c
@@ -56,7 +56,7 @@ static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
unsigned int ret;
struct rm_feature_desc *desc;
struct ata_taskfile tf;
- static const char cdb[] = { GPCMD_GET_CONFIGURATION,
+ static const char cdb[ATAPI_CDB_LEN] = { GPCMD_GET_CONFIGURATION,
2, /* only 1 feature descriptor requested */
0, 3, /* 3, removable medium feature */
0, 0, 0,/* reserved */