CVE-2022-49363

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix to do sanity check on block address in f2fs_do_zero_range()

As Yanming reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=215894

I have encountered a bug in F2FS file system in kernel v5.17.

I have uploaded the system call sequence as case.c, and a fuzzed image can

be found in google net disk

The kernel should enable CONFIG_KASAN=y and CONFIG_KASAN_INLINE=y. You can

reproduce the bug by running the following commands:

kernel BUG at fs/f2fs/segment.c:2291!

Call Trace:

f2fs_invalidate_blocks+0x193/0x2d0

f2fs_fallocate+0x2593/0x4a70

vfs_fallocate+0x2a5/0xac0

ksys_fallocate+0x35/0x70

__x64_sys_fallocate+0x8e/0xf0

do_syscall_64+0x3b/0x90

entry_SYSCALL_64_after_hwframe+0x44/0xae

The root cause is, after image was fuzzed, block mapping info in inode

will be inconsistent with SIT table, so in f2fs_fallocate(), it will cause

panic when updating SIT with invalid blkaddr.

Let's fix the issue by adding sanity check on block address before updating

SIT table with it.