Hi, developers,

This is Chenglong Tang from the Google Container Optimized OS team. We recently received a kernel panic bug from the customers regarding cifs. 

This happened since the backport of following changes in cifs(in our kernel COS-5.10.208 and COS-5.15.146):

cifs: Fix non-availability of dedup breaking generic/304: https://lore.kernel.org/r/3876191.1701555260@warthog.procyon.org.uk/

smb: client: fix potential NULL deref in parse_dfs_referrals(): Upstream commit 92414333eb375ed64f4ae92d34d579e826936480

ksmbd: fix wrong name of SMB2_CREATE_ALLOCATION_SIZE: Upstream commit  13736654481198e519059d4a2e2e3b20fa9fdb3e

smb: client: fix NULL deref in asn1_ber_decoder(): Upstream commit 90d025c2e953c11974e76637977c473200593a46

smb: a few more smb changes...

The line that crashed is line 197 in fs/cifs/dfs_cache.c

```

if (unlikely(strcmp(cp->charset, cache_cp->charset))) {

```

I attached the dmesg and backtrace for debugging purposes. Let me know if you need more information.

Best,

Chenglong