diff options
author | Coly Li <colyli@suse.de> | 2019-02-09 12:53:10 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-27 09:33:51 +0200 |
commit | d775179e00cdc6fed4c33fef92dcfb24a797e39e (patch) | |
tree | 943abc660f7f66b78e0d6390dee7a7afc92bd0c7 | |
parent | b25147b49301454409d9e38b0cbd46221be089a8 (diff) |
bcache: fix input overflow to cache set sysfs file io_error_halflife
[ Upstream commit a91fbda49f746119828f7e8ad0f0aa2ab0578f65 ]
Cache set sysfs entry io_error_halflife is used to set c->error_decay.
c->error_decay is in type unsigned int, and it is converted by
strtoul_or_return(), therefore overflow to c->error_decay is possible
for a large input value.
This patch fixes the overflow by using strtoul_safe_clamp() to convert
input string to an unsigned long value in range [0, UINT_MAX], then
divides by 88 and set it to c->error_decay.
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/md/bcache/sysfs.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 5a5c1f1bd8a5..87daccbbc61b 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -645,8 +645,17 @@ STORE(__bch_cache_set) c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT; /* See count_io_errors() for why 88 */ - if (attr == &sysfs_io_error_halflife) - c->error_decay = strtoul_or_return(buf) / 88; + if (attr == &sysfs_io_error_halflife) { + unsigned long v = 0; + ssize_t ret; + + ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX); + if (!ret) { + c->error_decay = v / 88; + return size; + } + return ret; + } sysfs_strtoul(journal_delay_ms, c->journal_delay_ms); sysfs_strtoul(verify, c->verify); |