From 63bfe841053f8dda09c9d059d543486d9dc16104 Mon Sep 17 00:00:00 2001 From: Baokun Li Date: Tue, 19 Mar 2024 19:33:22 +0800 Subject: [PATCH] ext4: add positive int attr pointer to avoid sysfs variables overflow The following variables controlled by the sysfs interface are of type int and are normally used in the range [0, INT_MAX], but are declared as attr_pointer_ui, and thus may be set to values that exceed INT_MAX and result in overflows to get negative values. err_ratelimit_burst msg_ratelimit_burst warning_ratelimit_burst err_ratelimit_interval_ms msg_ratelimit_interval_ms warning_ratelimit_interval_ms Therefore, we add attr_pointer_pi (aka positive int attr pointer) with a value range of 0-INT_MAX to avoid overflow. Signed-off-by: Baokun Li Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20240319113325.3110393-7-libaokun1@huawei.com Signed-off-by: Theodore Ts'o --- fs/ext4/sysfs.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index 8e0473169458..ddb54608ca2e 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -32,6 +32,7 @@ typedef enum { attr_clusters_in_group, attr_mb_order, attr_feature, + attr_pointer_pi, attr_pointer_ui, attr_pointer_ul, attr_pointer_u64, @@ -180,6 +181,9 @@ static struct ext4_attr ext4_attr_##_name = { \ #define EXT4_RO_ATTR_ES_STRING(_name,_elname,_size) \ EXT4_ATTR_STRING(_name, 0444, _size, ext4_super_block, _elname) +#define EXT4_RW_ATTR_SBI_PI(_name,_elname) \ + EXT4_ATTR_OFFSET(_name, 0644, pointer_pi, ext4_sb_info, _elname) + #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \ EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname) @@ -222,12 +226,12 @@ EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); EXT4_RW_ATTR_SBI_UI(mb_max_linear_groups, s_mb_max_linear_groups); EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error); -EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); -EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); -EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); -EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); -EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); -EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); +EXT4_RW_ATTR_SBI_PI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_PI(err_ratelimit_burst, s_err_ratelimit_state.burst); +EXT4_RW_ATTR_SBI_PI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_PI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); +EXT4_RW_ATTR_SBI_PI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_PI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); #ifdef CONFIG_EXT4_DEBUG EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail); #endif @@ -382,6 +386,7 @@ static ssize_t ext4_generic_attr_show(struct ext4_attr *a, case attr_inode_readahead: case attr_clusters_in_group: case attr_mb_order: + case attr_pointer_pi: case attr_pointer_ui: if (a->attr_ptr == ptr_ext4_super_block_offset) return sysfs_emit(buf, "%u\n", le32_to_cpup(ptr)); @@ -452,6 +457,14 @@ static ssize_t ext4_generic_attr_store(struct ext4_attr *a, return 0; switch (a->attr_id) { + case attr_pointer_pi: + ret = kstrtouint(skip_spaces(buf), 0, &t); + if (ret) + return ret; + if ((int)t < 0) + return -EINVAL; + *((unsigned int *) ptr) = t; + return len; case attr_pointer_ui: ret = kstrtouint(skip_spaces(buf), 0, &t); if (ret)