kafs: addr_prefs: Too many elements in string
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WARNING: lock held when returning to user space!
6.13.0-rc5-syzkaller-00006-g56e6a3499e14 #0 Not tainted
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syz.3.39/6137 is leaving the kernel with locks still held!
1 lock held by syz.3.39/6137:
 #0: ffff8880755ac190 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
 #0: ffff8880755ac190 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: afs_proc_addr_prefs_write+0x2bb/0x14e0 fs/afs/addr_prefs.c:388