evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

bcache: fix input overflow to sequential_cutoff

Browse source 
[ Upstream commit 8c27a3953e92eb0b22dbb03d599f543a05f9574e ]

People may set sequential_cutoff of a cached device via sysfs file,
but current code does not check input value overflow. E.g. if value
4294967295 (UINT_MAX) is written to file sequential_cutoff, its value
is 4GB, but if 4294967296 (UINT_MAX + 1) is written into, its value
will be 0. This is an unexpected behavior.

This patch replaces d_strtoi_h() by sysfs_strtoul_clamp() to convert
input string to unsigned integer value, and limit its range in
[0, UINT_MAX]. Then the input overflow can be fixed.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Coly Li 2019-02-09 12:53:01 +08:00 • committed by Greg Kroah-Hartman
parent d775179e00
commit 97f00d95df
1 changed files with 3 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/md/bcache/sysfs.c
View file

@ -215,7 +215,9 @@ STORE(__cached_dev)
d_strtoul(writeback_rate_d_term);
d_strtoul_nonzero(writeback_rate_p_term_inverse);
d_strtoi_h(sequential_cutoff);
sysfs_strtoul_clamp(sequential_cutoff,
dc->sequential_cutoff,
0, UINT_MAX);
d_strtoi_h(readahead);
if (attr == &sysfs_clear_stats)