CVE-2022-49708

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ext4: fix bug_on ext4_mb_use_inode_pa<br /> <br /> Hulk Robot reported a BUG_ON:<br /> ==================================================================<br /> kernel BUG at fs/ext4/mballoc.c:3211!<br /> [...]<br /> RIP: 0010:ext4_mb_mark_diskspace_used.cold+0x85/0x136f<br /> [...]<br /> Call Trace:<br /> ext4_mb_new_blocks+0x9df/0x5d30<br /> ext4_ext_map_blocks+0x1803/0x4d80<br /> ext4_map_blocks+0x3a4/0x1a10<br /> ext4_writepages+0x126d/0x2c30<br /> do_writepages+0x7f/0x1b0<br /> __filemap_fdatawrite_range+0x285/0x3b0<br /> file_write_and_wait_range+0xb1/0x140<br /> ext4_sync_file+0x1aa/0xca0<br /> vfs_fsync_range+0xfb/0x260<br /> do_fsync+0x48/0xa0<br /> [...]<br /> ==================================================================<br /> <br /> Above issue may happen as follows:<br /> -------------------------------------<br /> do_fsync<br /> vfs_fsync_range<br /> ext4_sync_file<br /> file_write_and_wait_range<br /> __filemap_fdatawrite_range<br /> do_writepages<br /> ext4_writepages<br /> mpage_map_and_submit_extent<br /> mpage_map_one_extent<br /> ext4_map_blocks<br /> ext4_mb_new_blocks<br /> ext4_mb_normalize_request<br /> &gt;&gt;&gt; start + size ac_o_ex.fe_logical<br /> ext4_mb_regular_allocator<br /> ext4_mb_simple_scan_group<br /> ext4_mb_use_best_found<br /> ext4_mb_new_preallocation<br /> ext4_mb_new_inode_pa<br /> ext4_mb_use_inode_pa<br /> &gt;&gt;&gt; set ac-&gt;ac_b_ex.fe_len &gt;&gt; BUG_ON(ac-&gt;ac_b_ex.fe_len