Re: [PATCH v3] afs: Fix delayed allocation of a cell's anonymous key

[kernel test robot <lkp@intel.com>]

Hi David,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.18-rc7 next-20251128]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/David-Howells/afs-Fix-delayed-allocation-of-a-cell-s-anonymous-key/20251128-182016
base:   linus/master
patch link:    https://lore.kernel.org/r/800328.1764325145%40warthog.procyon.org.uk
patch subject: [PATCH v3] afs: Fix delayed allocation of a cell's anonymous key
config: riscv-allmodconfig (https://download.01.org/0day-ci/archive/20251129/202511291414.IgkEFchx-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project b3428bb966f1de8aa48375ffee0eba04ede133b7)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251129/202511291414.IgkEFchx-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511291414.IgkEFchx-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> fs/afs/security.c:29:6: warning: variable 'key' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
      29 |         if (!cell->anonymous_key) {
         |             ^~~~~~~~~~~~~~~~~~~~
   fs/afs/security.c:36:13: note: uninitialized use occurs here
      36 |         if (IS_ERR(key))
         |                    ^~~
   fs/afs/security.c:29:2: note: remove the 'if' if its condition is always true
      29 |         if (!cell->anonymous_key) {
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
   fs/afs/security.c:26:17: note: initialize the variable 'key' to silence this warning
      26 |         struct key *key;
         |                        ^
         |                         = NULL
   1 warning generated.


vim +29 fs/afs/security.c

    20	
    21	/*
    22	 * Allocate a key to use as a placeholder for anonymous user security.
    23	 */
    24	static int afs_alloc_anon_key(struct afs_cell *cell)
    25	{
    26		struct key *key;
    27	
    28		mutex_lock(&afs_key_lock);
  > 29		if (!cell->anonymous_key) {
    30			key = rxrpc_get_null_key(cell->key_desc);
    31			if (!IS_ERR(key))
    32				cell->anonymous_key = key;
    33		}
    34		mutex_unlock(&afs_key_lock);
    35	
    36		if (IS_ERR(key))
    37			return PTR_ERR(key);
    38	
    39		_debug("anon key %p{%x}",
    40		       cell->anonymous_key, key_serial(cell->anonymous_key));
    41		return 0;
    42	}
    43	

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