From: Baokun Li libaokun1@huawei.com
mainline inclusion from mainline-v6.10-rc1 commit 57341fe3179c7694c92dcf99e7f836cee4c800dd category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAD018 CVE: CVE-2024-40955
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Refactor out the function ext4_generic_attr_show() to handle the reading of values of various common types, with no functional changes.
Signed-off-by: Baokun Li libaokun1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/20240319113325.3110393-4-libaokun1@huawei.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Yifan Qiao qiaoyifan4@huawei.com --- fs/ext4/sysfs.c | 74 +++++++++++++++++++++---------------------------- 1 file changed, 32 insertions(+), 42 deletions(-)
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index 2b1c529b7fdf..7f455b5f22c0 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -366,13 +366,42 @@ static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi) #define print_tstamp(buf, es, tstamp) \ __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)
+static ssize_t ext4_generic_attr_show(struct ext4_attr *a, + struct ext4_sb_info *sbi, char *buf) +{ + void *ptr = calc_ptr(a, sbi); + + if (!ptr) + return 0; + + switch (a->attr_id) { + case attr_inode_readahead: + case attr_pointer_ui: + if (a->attr_ptr == ptr_ext4_super_block_offset) + return sysfs_emit(buf, "%u\n", le32_to_cpup(ptr)); + return sysfs_emit(buf, "%u\n", *((unsigned int *) ptr)); + case attr_pointer_ul: + return sysfs_emit(buf, "%lu\n", *((unsigned long *) ptr)); + case attr_pointer_u8: + return sysfs_emit(buf, "%u\n", *((unsigned char *) ptr)); + case attr_pointer_u64: + if (a->attr_ptr == ptr_ext4_super_block_offset) + return sysfs_emit(buf, "%llu\n", le64_to_cpup(ptr)); + return sysfs_emit(buf, "%llu\n", *((unsigned long long *) ptr)); + case attr_pointer_string: + return sysfs_emit(buf, "%.*s\n", a->attr_size, (char *) ptr); + case attr_pointer_atomic: + return sysfs_emit(buf, "%d\n", atomic_read((atomic_t *) ptr)); + } + return 0; +} + static ssize_t ext4_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, s_kobj); struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); - void *ptr = calc_ptr(a, sbi);
switch (a->attr_id) { case attr_delayed_allocation_blocks: @@ -391,45 +420,6 @@ static ssize_t ext4_attr_show(struct kobject *kobj, return sysfs_emit(buf, "%llu\n", (unsigned long long) percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit)); - case attr_inode_readahead: - case attr_pointer_ui: - if (!ptr) - return 0; - if (a->attr_ptr == ptr_ext4_super_block_offset) - return sysfs_emit(buf, "%u\n", - le32_to_cpup(ptr)); - else - return sysfs_emit(buf, "%u\n", - *((unsigned int *) ptr)); - case attr_pointer_ul: - if (!ptr) - return 0; - return sysfs_emit(buf, "%lu\n", - *((unsigned long *) ptr)); - case attr_pointer_u8: - if (!ptr) - return 0; - return sysfs_emit(buf, "%u\n", - *((unsigned char *) ptr)); - case attr_pointer_u64: - if (!ptr) - return 0; - if (a->attr_ptr == ptr_ext4_super_block_offset) - return sysfs_emit(buf, "%llu\n", - le64_to_cpup(ptr)); - else - return sysfs_emit(buf, "%llu\n", - *((unsigned long long *) ptr)); - case attr_pointer_string: - if (!ptr) - return 0; - return sysfs_emit(buf, "%.*s\n", a->attr_size, - (char *) ptr); - case attr_pointer_atomic: - if (!ptr) - return 0; - return sysfs_emit(buf, "%d\n", - atomic_read((atomic_t *) ptr)); case attr_feature: return sysfs_emit(buf, "supported\n"); case attr_first_error_time: @@ -438,9 +428,9 @@ static ssize_t ext4_attr_show(struct kobject *kobj, return print_tstamp(buf, sbi->s_es, s_last_error_time); case attr_journal_task: return journal_task_show(sbi, buf); + default: + return ext4_generic_attr_show(a, sbi, buf); } - - return 0; }
static ssize_t ext4_generic_attr_store(struct ext4_attr *a,