nilfs2: fix OOB in nilfs_set_de_type

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix OOB in nilfs_set_de_type The size of the nilfs_type_by_mode array in the fs/nilfs2/dir.c file is defined as "S_IFMT >> S_SHIFT", but the nilfs_set_de_type() function, which uses this array, specifies the index to read from the array in the same way as "(mode & S_IFMT) >> S_SHIFT". static void nilfs_set_de_type(struct nilfs_dir_entry *de, struct inode *inode) { umode_t mode = inode->i_mode; de->file_type = nilfs_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; // oob } However, when the index is determined this way, an out-of-bounds (OOB) error occurs by referring to an index that is 1 larger than the array size when the condition "mode & S_IFMT == S_IFMT" is satisfied. Therefore, a patch to resize the nilfs_type_by_mode array should be applied to prevent OOB errors.

References

• https://git.kernel.org/stable/c/054f29e9ca05be3906544c5f2a2c7321c30a4243
• https://git.kernel.org/stable/c/90f43980ea6be4ad903e389be9a27a2a0018f1c8
• https://git.kernel.org/stable/c/7061c7efbb9e8f11ce92d6b4646405ea2b0b4de1
• https://git.kernel.org/stable/c/bdbe483da21f852c93b22557b146bc4d989260f0
• https://git.kernel.org/stable/c/897ac5306bbeb83e90c437326f7044c79a17c611
• https://git.kernel.org/stable/c/2382eae66b196c31893984a538908c3eb7506ff9
• https://git.kernel.org/stable/c/90823f8d9ecca3d5fa6b102c8e464c62f416975f
• https://git.kernel.org/stable/c/c4a7dc9523b59b3e73fd522c73e95e072f876b16