CC: [email protected] CC: [email protected] TO: Coly Li <[email protected]>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/colyli/linux-bcache.git for-next head: d521ed6f859f0027a89ca40c1ce17240f8e118f4 commit: d5532e5a2b74d5c4ff9b847f89720c146599f700 [11/12] bcache: read jset from NVDIMM pages for journal replay :::::: branch date: 25 hours ago :::::: commit date: 25 hours ago config: i386-randconfig-m021-20211126 (https://download.01.org/0day-ci/archive/20211127/[email protected]/config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> Reported-by: Dan Carpenter <[email protected]> smatch warnings: drivers/md/bcache/journal.c:123 journal_read_bucket() error: potentially dereferencing uninitialized 'j'. vim +/j +123 drivers/md/bcache/journal.c cafe563591446cf Kent Overstreet 2013-03-23 115 cafe563591446cf Kent Overstreet 2013-03-23 116 /* This function could be simpler now since we no longer write cafe563591446cf Kent Overstreet 2013-03-23 117 * journal entries that overlap bucket boundaries; this means cafe563591446cf Kent Overstreet 2013-03-23 118 * the start of a bucket will always have a valid journal entry cafe563591446cf Kent Overstreet 2013-03-23 119 * if it has any journal entries at all. cafe563591446cf Kent Overstreet 2013-03-23 120 */ cafe563591446cf Kent Overstreet 2013-03-23 121 while (len) { cafe563591446cf Kent Overstreet 2013-03-23 122 struct list_head *where; cafe563591446cf Kent Overstreet 2013-03-23 @123 size_t blocks, bytes = set_bytes(j); cafe563591446cf Kent Overstreet 2013-03-23 124 b3fa7e77e67e647 Kent Overstreet 2013-08-05 125 if (j->magic != jset_magic(&ca->sb)) { 46f5aa8806e34f2 Joe Perches 2020-05-27 126 pr_debug("%u: bad magic\n", bucket_index); cafe563591446cf Kent Overstreet 2013-03-23 127 return ret; b3fa7e77e67e647 Kent Overstreet 2013-08-05 128 } cafe563591446cf Kent Overstreet 2013-03-23 129 b3fa7e77e67e647 Kent Overstreet 2013-08-05 130 if (bytes > left << 9 || b3fa7e77e67e647 Kent Overstreet 2013-08-05 131 bytes > PAGE_SIZE << JSET_BITS) { 46f5aa8806e34f2 Joe Perches 2020-05-27 132 pr_info("%u: too big, %zu bytes, offset %u\n", b3fa7e77e67e647 Kent Overstreet 2013-08-05 133 bucket_index, bytes, offset); cafe563591446cf Kent Overstreet 2013-03-23 134 return ret; b3fa7e77e67e647 Kent Overstreet 2013-08-05 135 } cafe563591446cf Kent Overstreet 2013-03-23 136 cafe563591446cf Kent Overstreet 2013-03-23 137 if (bytes > len << 9) cafe563591446cf Kent Overstreet 2013-03-23 138 goto reread; cafe563591446cf Kent Overstreet 2013-03-23 139 b3fa7e77e67e647 Kent Overstreet 2013-08-05 140 if (j->csum != csum_set(j)) { 46f5aa8806e34f2 Joe Perches 2020-05-27 141 pr_info("%u: bad csum, %zu bytes, offset %u\n", b3fa7e77e67e647 Kent Overstreet 2013-08-05 142 bucket_index, bytes, offset); cafe563591446cf Kent Overstreet 2013-03-23 143 return ret; b3fa7e77e67e647 Kent Overstreet 2013-08-05 144 } cafe563591446cf Kent Overstreet 2013-03-23 145 4e1ebae3ee4e0ce Coly Li 2020-10-01 146 blocks = set_blocks(j, block_bytes(ca)); cafe563591446cf Kent Overstreet 2013-03-23 147 2464b693148e5d5 Coly Li 2019-06-28 148 /* 2464b693148e5d5 Coly Li 2019-06-28 149 * Nodes in 'list' are in linear increasing order of 2464b693148e5d5 Coly Li 2019-06-28 150 * i->j.seq, the node on head has the smallest (oldest) 2464b693148e5d5 Coly Li 2019-06-28 151 * journal seq, the node on tail has the biggest 2464b693148e5d5 Coly Li 2019-06-28 152 * (latest) journal seq. 2464b693148e5d5 Coly Li 2019-06-28 153 */ 2464b693148e5d5 Coly Li 2019-06-28 154 2464b693148e5d5 Coly Li 2019-06-28 155 /* 2464b693148e5d5 Coly Li 2019-06-28 156 * Check from the oldest jset for last_seq. If 2464b693148e5d5 Coly Li 2019-06-28 157 * i->j.seq < j->last_seq, it means the oldest jset 2464b693148e5d5 Coly Li 2019-06-28 158 * in list is expired and useless, remove it from 9c9b81c45619e76 Bhaskar Chowdhury 2021-04-11 159 * this list. Otherwise, j is a candidate jset for 2464b693148e5d5 Coly Li 2019-06-28 160 * further following checks. 2464b693148e5d5 Coly Li 2019-06-28 161 */ cafe563591446cf Kent Overstreet 2013-03-23 162 while (!list_empty(list)) { cafe563591446cf Kent Overstreet 2013-03-23 163 i = list_first_entry(list, cafe563591446cf Kent Overstreet 2013-03-23 164 struct journal_replay, list); cafe563591446cf Kent Overstreet 2013-03-23 165 if (i->j.seq >= j->last_seq) cafe563591446cf Kent Overstreet 2013-03-23 166 break; cafe563591446cf Kent Overstreet 2013-03-23 167 list_del(&i->list); cafe563591446cf Kent Overstreet 2013-03-23 168 kfree(i); cafe563591446cf Kent Overstreet 2013-03-23 169 } cafe563591446cf Kent Overstreet 2013-03-23 170 2464b693148e5d5 Coly Li 2019-06-28 171 /* iterate list in reverse order (from latest jset) */ cafe563591446cf Kent Overstreet 2013-03-23 172 list_for_each_entry_reverse(i, list, list) { cafe563591446cf Kent Overstreet 2013-03-23 173 if (j->seq == i->j.seq) cafe563591446cf Kent Overstreet 2013-03-23 174 goto next_set; cafe563591446cf Kent Overstreet 2013-03-23 175 2464b693148e5d5 Coly Li 2019-06-28 176 /* 2464b693148e5d5 Coly Li 2019-06-28 177 * if j->seq is less than any i->j.last_seq 2464b693148e5d5 Coly Li 2019-06-28 178 * in list, j is an expired and useless jset. 2464b693148e5d5 Coly Li 2019-06-28 179 */ cafe563591446cf Kent Overstreet 2013-03-23 180 if (j->seq < i->j.last_seq) cafe563591446cf Kent Overstreet 2013-03-23 181 goto next_set; cafe563591446cf Kent Overstreet 2013-03-23 182 2464b693148e5d5 Coly Li 2019-06-28 183 /* 2464b693148e5d5 Coly Li 2019-06-28 184 * 'where' points to first jset in list which 2464b693148e5d5 Coly Li 2019-06-28 185 * is elder then j. 2464b693148e5d5 Coly Li 2019-06-28 186 */ cafe563591446cf Kent Overstreet 2013-03-23 187 if (j->seq > i->j.seq) { cafe563591446cf Kent Overstreet 2013-03-23 188 where = &i->list; cafe563591446cf Kent Overstreet 2013-03-23 189 goto add; cafe563591446cf Kent Overstreet 2013-03-23 190 } cafe563591446cf Kent Overstreet 2013-03-23 191 } cafe563591446cf Kent Overstreet 2013-03-23 192 cafe563591446cf Kent Overstreet 2013-03-23 193 where = list; cafe563591446cf Kent Overstreet 2013-03-23 194 add: cafe563591446cf Kent Overstreet 2013-03-23 195 i = kmalloc(offsetof(struct journal_replay, j) + cafe563591446cf Kent Overstreet 2013-03-23 196 bytes, GFP_KERNEL); cafe563591446cf Kent Overstreet 2013-03-23 197 if (!i) cafe563591446cf Kent Overstreet 2013-03-23 198 return -ENOMEM; cafe563591446cf Kent Overstreet 2013-03-23 199 memcpy(&i->j, j, bytes); 2464b693148e5d5 Coly Li 2019-06-28 200 /* Add to the location after 'where' points to */ cafe563591446cf Kent Overstreet 2013-03-23 201 list_add(&i->list, where); cafe563591446cf Kent Overstreet 2013-03-23 202 ret = 1; cafe563591446cf Kent Overstreet 2013-03-23 203 a231f07a5fe30a5 Coly Li 2019-06-28 204 if (j->seq > ja->seq[bucket_index]) cafe563591446cf Kent Overstreet 2013-03-23 205 ja->seq[bucket_index] = j->seq; cafe563591446cf Kent Overstreet 2013-03-23 206 next_set: cafe563591446cf Kent Overstreet 2013-03-23 207 offset += blocks * ca->sb.block_size; cafe563591446cf Kent Overstreet 2013-03-23 208 len -= blocks * ca->sb.block_size; cafe563591446cf Kent Overstreet 2013-03-23 209 j = ((void *) j) + blocks * block_bytes(ca); cafe563591446cf Kent Overstreet 2013-03-23 210 } cafe563591446cf Kent Overstreet 2013-03-23 211 } cafe563591446cf Kent Overstreet 2013-03-23 212 cafe563591446cf Kent Overstreet 2013-03-23 213 return ret; cafe563591446cf Kent Overstreet 2013-03-23 214 } cafe563591446cf Kent Overstreet 2013-03-23 215 :::::: The code at line 123 was first introduced by commit :::::: cafe563591446cf80bfbc2fe3bc72a2e36cf1060 bcache: A block layer cache :::::: TO: Kent Overstreet <[email protected]> :::::: CC: Kent Overstreet <[email protected]> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/[email protected] _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
