[PATCH 3.16 162/366] mtd: cfi_cmdset_0002: fix SEGV unlocking multiple chips

Ben Hutchings
2018-11-11T19:49:05Z

From: Joakim Tjernlund <joakim.tjernlund@infinera.com>

commit 5fdfc3dbad099281bf027a353d5786c09408a8e5 upstream.

cfi_ppb_unlock() tries to relock all sectors that were locked before
unlocking the whole chip.
This locking used the chip start address + the FULL offset from the
first flash chip, thereby forming an illegal address. Fix that by using
the chip offset(adr).

Fixes: 1648eaaa1575 ("mtd: cfi_cmdset_0002: Support Persistent Protection Bits (PPB) locking")
Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/mtd/chips/cfi_cmdset_0002.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -2206,7 +2206,7 @@ static int cfi_atmel_unlock(struct mtd_i

struct ppb_lock {
struct flchip *chip;
- loff_t offset;
+ unsigned long adr;
int locked;
};

@@ -2342,7 +2342,7 @@ static int __maybe_unused cfi_ppb_unlock
*/
if ((adr < ofs) || (adr >= (ofs + len))) {
sect[sectors].chip = &cfi->chips[chipnum];
- sect[sectors].offset = offset;
+ sect[sectors].adr = adr;
sect[sectors].locked = do_ppb_xxlock(
map, &cfi->chips[chipnum], adr, 0,
DO_XXLOCK_ONEBLOCK_GETLOCK);
@@ -2386,7 +2386,7 @@ static int __maybe_unused cfi_ppb_unlock
*/
for (i = 0; i < sectors; i++) {
if (sect[i].locked)
- do_ppb_xxlock(map, sect[i].chip, sect[i].offset, 0,
+ do_ppb_xxlock(map, sect[i].chip, sect[i].adr, 0,
DO_XXLOCK_ONEBLOCK_LOCK);
}