From 58a4e23703b22c331b01fbd0c12161aadaa6d50b Mon Sep 17 00:00:00 2001 From: =?utf8?q?Mats=20K=C3=A4rrman?= Date: Wed, 21 Aug 2013 13:24:49 +0000 Subject: [PATCH] UBIFS: correct data corruption range With power-cut emulation, it is possible that sometimes no data at all is corrupted and that confusing messages are printed due to errors in the computation of data corruption range. [1] The start of the range should be [0..len-1], not [0..len]. [2] The end of the range should always be at least 1 greater than the start. Signed-off-by: Mats Karrman Signed-off-by: Artem Bityutskiy --- fs/ubifs/debug.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c index 6e025e0..cc1febd 100644 --- a/fs/ubifs/debug.c +++ b/fs/ubifs/debug.c @@ -2563,9 +2563,9 @@ static int corrupt_data(const struct ubifs_info *c, const void *buf, unsigned int from, to, ffs = chance(1, 2); unsigned char *p = (void *)buf; - from = prandom_u32() % (len + 1); - /* Corruption may only span one max. write unit */ - to = min(len, ALIGN(from, c->max_write_size)); + from = prandom_u32() % len; + /* Corruption span max to end of write unit */ + to = min(len, ALIGN(from + 1, c->max_write_size)); ubifs_warn("filled bytes %u-%u with %s", from, to - 1, ffs ? "0xFFs" : "random data"); -- 2.7.4