diff options
| author | Dehe Gu <gudehe@huawei.com> | 2020-07-03 17:51:29 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2020-07-08 10:11:19 -0700 |
| commit | ffcde4b29a5f20ddca6fe559b48f345818bf1d91 (patch) | |
| tree | fef8377613d93f472079d9618bc4f7f0bdee7867 /fs/f2fs | |
| parent | 0e5e81114de1c4ac32e36f057256653a04f27a33 (diff) | |
f2fs: remove write attribute of main_blkaddr sysfs node
Fuzzing main_blkaddr sysfs node will corrupt this field's value,
causing kernel panic, remove its write attribute to avoid potential
security risk.
[Chao Yu: add description]
Signed-off-by: Dehe Gu <gudehe@huawei.com>
Signed-off-by: Daiyue Zhang <zhangdaiyue1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs')
| -rw-r--r-- | fs/f2fs/sysfs.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c index 2a140657fc4d..50524401c8e6 100644 --- a/fs/f2fs/sysfs.c +++ b/fs/f2fs/sysfs.c @@ -223,6 +223,13 @@ static ssize_t avg_vblocks_show(struct f2fs_attr *a, } #endif +static ssize_t main_blkaddr_show(struct f2fs_attr *a, + struct f2fs_sb_info *sbi, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%llu\n", + (unsigned long long)MAIN_BLKADDR(sbi)); +} + static ssize_t f2fs_sbi_show(struct f2fs_attr *a, struct f2fs_sb_info *sbi, char *buf) { @@ -526,7 +533,6 @@ F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time); F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_idle, gc_mode); F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_urgent, gc_mode); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments); -F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, main_blkaddr, main_blkaddr); F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_small_discards, max_discards); F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_granularity, discard_granularity); F2FS_RW_ATTR(RESERVED_BLOCKS, f2fs_sb_info, reserved_blocks, reserved_blocks); @@ -569,6 +575,7 @@ F2FS_GENERAL_RO_ATTR(current_reserved_blocks); F2FS_GENERAL_RO_ATTR(unusable); F2FS_GENERAL_RO_ATTR(encoding); F2FS_GENERAL_RO_ATTR(mounted_time_sec); +F2FS_GENERAL_RO_ATTR(main_blkaddr); #ifdef CONFIG_F2FS_STAT_FS F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_foreground_calls, cp_count); F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_background_calls, bg_cp_count); |