mtd: mtdconcat: prevent a read from eraseregions[-1]
If the erase region was found in the first iteration we read from
eraseregions[-1]
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 792b547..db6de74 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -427,7 +427,7 @@
* to-be-erased area begins. Verify that the starting
* offset is aligned to this region's erase size:
*/
- if (instr->addr & (erase_regions[i].erasesize - 1))
+ if (i < 0 || instr->addr & (erase_regions[i].erasesize - 1))
return -EINVAL;
/*
@@ -440,8 +440,8 @@
/*
* check if the ending offset is aligned to this region's erase size
*/
- if ((instr->addr + instr->len) & (erase_regions[i].erasesize -
- 1))
+ if (i < 0 || ((instr->addr + instr->len) &
+ (erase_regions[i].erasesize - 1)))
return -EINVAL;
}