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| author | Dongsheng Yang <yangds.fnst@cn.fujitsu.com> | 2015-09-30 09:01:19 +0800 |
|---|---|---|
| committer | Brian Norris <computersforpeace@gmail.com> | 2015-10-19 18:08:33 -0700 |
| commit | ab84fce518175aa09ec6e1bb50c2b41dad3e610a (patch) | |
| tree | c21e33b3f6907e7c3f46bef21d7119e394db0636 | |
| parent | d3e94f3f2c0f669dfa0d0d51645d5d7d13a9c074 (diff) | |
| download | linux-ab84fce518175aa09ec6e1bb50c2b41dad3e610a.tar.bz2 | |
mtd: mtdram: check offs and len in mtdram->erase
We should prevent user to erasing mtd device with
an unaligned offset or length.
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
| -rw-r--r-- | drivers/mtd/devices/mtdram.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c index 8e285089229c..627a9bc37679 100644 --- a/drivers/mtd/devices/mtdram.c +++ b/drivers/mtd/devices/mtdram.c @@ -32,8 +32,29 @@ MODULE_PARM_DESC(erase_size, "Device erase block size in KiB"); // We could store these in the mtd structure, but we only support 1 device.. static struct mtd_info *mtd_info; +static int check_offs_len(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + int ret = 0; + + /* Start address must align on block boundary */ + if (mtd_mod_by_eb(ofs, mtd)) { + pr_debug("%s: unaligned address\n", __func__); + ret = -EINVAL; + } + + /* Length must align on block boundary */ + if (mtd_mod_by_eb(len, mtd)) { + pr_debug("%s: length not block aligned\n", __func__); + ret = -EINVAL; + } + + return ret; +} + static int ram_erase(struct mtd_info *mtd, struct erase_info *instr) { + if (check_offs_len(mtd, instr->addr, instr->len)) + return -EINVAL; memset((char *)mtd->priv + instr->addr, 0xff, instr->len); instr->state = MTD_ERASE_DONE; mtd_erase_callback(instr); |