Dmitry Monakhov 794446c694 jbd2: fix race between jbd2_journal_remove_checkpoint and ->j_commit_callback ... The following race is possible: [kjournald2] other_task jbd2_journal_commit_transaction() j_state = T_FINISHED; spin_unlock(&journal->j_list_lock); ->jbd2_journal_remove_checkpoint() ->jbd2_journal_free_transaction(); ->kmem_cache_free(transaction) ->j_commit_callback(journal, transaction); -> USE_AFTER_FREE WARNING: at lib/list_debug.c:62 __list_del_entry+0x1c0/0x250() Hardware name: list_del corruption. prev->next should be ffff88019a4ec198, but was 6b6b6b6b6b6b6b6b Modules linked in: cpufreq_ondemand acpi_cpufreq freq_table mperf coretemp kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode sg xhci_hcd button sd_mod crc_t10dif aesni_intel ablk_helper cryptd lrw aes_x86_64 xts gf128mul ahci libahci pata_acpi ata_generic dm_mirror dm_region_hash dm_log dm_mod Pid: 16400, comm: jbd2/dm-1-8 Tainted: G W 3.8.0-rc3+ #107 Call Trace: [<ffffffff8106fb0d>] warn_slowpath_common+0xad/0xf0 [<ffffffff8106fc06>] warn_slowpath_fmt+0x46/0x50 [<ffffffff813637e9>] ? ext4_journal_commit_callback+0x99/0xc0 [<ffffffff8148cae0>] __list_del_entry+0x1c0/0x250 [<ffffffff813637bf>] ext4_journal_commit_callback+0x6f/0xc0 [<ffffffff813ca336>] jbd2_journal_commit_transaction+0x23a6/0x2570 [<ffffffff8108aa42>] ? try_to_del_timer_sync+0x82/0xa0 [<ffffffff8108b491>] ? del_timer_sync+0x91/0x1e0 [<ffffffff813d3ecf>] kjournald2+0x19f/0x6a0 [<ffffffff810ad630>] ? wake_up_bit+0x40/0x40 [<ffffffff813d3d30>] ? bit_spin_lock+0x80/0x80 [<ffffffff810ac6be>] kthread+0x10e/0x120 [<ffffffff810ac5b0>] ? __init_kthread_worker+0x70/0x70 [<ffffffff818ff6ac>] ret_from_fork+0x7c/0xb0 [<ffffffff810ac5b0>] ? __init_kthread_worker+0x70/0x70 In order to demonstrace this issue one should mount ext4 with mount -o discard option on SSD disk. This makes callback longer and race window becomes wider. In order to fix this we should mark transaction as finished only after callbacks have completed Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org		2013-04-03 22:06:52 -04:00
..
checkpoint.c
commit.c	jbd2: fix race between jbd2_journal_remove_checkpoint and ->j_commit_callback	2013-04-03 22:06:52 -04:00
journal.c	ext4/jbd2: don't wait (forever) for stale tid caused by wraparound	2013-04-03 22:02:52 -04:00
Kconfig
Makefile
recovery.c	jbd2: check return value of blkdev_issue_flush()	2012-08-17 09:56:17 -04:00
revoke.c
transaction.c	jbd2: fix use after free in jbd2_journal_dirty_metadata()	2013-03-11 13:24:56 -04:00