mm/kasan/report_tags.c:63 kasan_complete_mode_report_info() error: we previously assumed 'info->cache' could be null (see line 37)

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

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: Andrey Konovalov <andreyknvl@google.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Linux Memory Management List <linux-mm@kvack.org>
CC: Alexander Potapenko <glider@google.com>

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   075dbe9f6e3c21596c5245826a4ee1f1c1676eb8
commit: 7d88e4f768b0fdb85b68f0e4679bb10fdb05c808 kasan: check object_size in kasan_complete_mode_report_info
date:   10 months ago
:::::: branch date: 22 hours ago
:::::: commit date: 10 months ago
config: arm64-randconfig-r071-20240923 (https://download.01.org/0day-ci/archive/20240928/202409280119.7gzM9E4h-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 8663a75fa2f31299ab8d1d90288d9df92aadee88)

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>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202409280119.7gzM9E4h-lkp@intel.com/

smatch warnings:
mm/kasan/report_tags.c:63 kasan_complete_mode_report_info() error: we previously assumed 'info->cache' could be null (see line 37)

vim +63 mm/kasan/report_tags.c

b89933e9a54d3e Andrey Konovalov 2022-09-05  29  
59e6e098d1c156 Andrey Konovalov 2022-09-05  30  void kasan_complete_mode_report_info(struct kasan_report_info *info)
b89933e9a54d3e Andrey Konovalov 2022-09-05  31  {
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  32  	unsigned long flags;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  33  	u64 pos;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  34  	struct kasan_stack_ring_entry *entry;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  35  	bool alloc_found = false, free_found = false;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  36  
dcc579663f6073 Andrey Konovalov 2022-09-11 @37  	if ((!info->cache || !info->object) && !info->bug_type) {
1f538e1f2d294c Andrey Konovalov 2022-09-05  38  		info->bug_type = get_common_bug_type(info);
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  39  		return;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  40  	}
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  41  
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  42  	write_lock_irqsave(&stack_ring.lock, flags);
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  43  
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  44  	pos = atomic64_read(&stack_ring.pos);
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  45  
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  46  	/*
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  47  	 * The loop below tries to find stack ring entries relevant to the
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  48  	 * buggy object. This is a best-effort process.
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  49  	 *
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  50  	 * First, another object with the same tag can be allocated in place of
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  51  	 * the buggy object. Also, since the number of entries is limited, the
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  52  	 * entries relevant to the buggy object can be overwritten.
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  53  	 */
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  54  
80b92bfe3bb75a Andrey Konovalov 2022-09-05  55  	for (u64 i = pos - 1; i != pos - 1 - stack_ring.size; i--) {
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  56  		if (alloc_found && free_found)
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  57  			break;
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  58  
80b92bfe3bb75a Andrey Konovalov 2022-09-05  59  		entry = &stack_ring.entries[i % stack_ring.size];
7bc0584e5d2a68 Andrey Konovalov 2022-09-05  60  
f3b59798629940 Andrey Konovalov 2023-11-20  61  		if (kasan_reset_tag(entry->ptr) != info->object ||
7d88e4f768b0fd Andrey Konovalov 2023-11-20  62  		    get_tag(entry->ptr) != get_tag(info->access_addr) ||
7d88e4f768b0fd Andrey Konovalov 2023-11-20 @63  		    info->cache->object_size != entry->size)

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