From 0c031fd37f69deb0cd8c43bbfcfccd62ebd7e952 Mon Sep 17 00:00:00 2001 From: Xiao Ni Date: Fri, 10 Dec 2021 17:31:15 +0800 Subject: md: Move alloc/free acct bioset in to personality bioset acct is only needed for raid0 and raid5. Therefore, md_run only allocates it for raid0 and raid5. However, this does not cover personality takeover, which may cause uninitialized bioset. For example, the following repro steps: mdadm -CR /dev/md0 -l1 -n2 /dev/loop0 /dev/loop1 mdadm --wait /dev/md0 mkfs.xfs /dev/md0 mdadm /dev/md0 --grow -l5 mount /dev/md0 /mnt causes panic like: [ 225.933939] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 225.934903] #PF: supervisor instruction fetch in kernel mode [ 225.935639] #PF: error_code(0x0010) - not-present page [ 225.936361] PGD 0 P4D 0 [ 225.936677] Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN PTI [ 225.937525] CPU: 27 PID: 1133 Comm: mount Not tainted 5.16.0-rc3+ #706 [ 225.938416] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.module_el8.4.0+547+a85d02ba 04/01/2014 [ 225.939922] RIP: 0010:0x0 [ 225.940289] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. [ 225.941196] RSP: 0018:ffff88815897eff0 EFLAGS: 00010246 [ 225.941897] RAX: 0000000000000000 RBX: 0000000000092800 RCX: ffffffff81370a39 [ 225.942813] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000092800 [ 225.943772] RBP: 1ffff1102b12fe04 R08: fffffbfff0b43c01 R09: fffffbfff0b43c01 [ 225.944807] R10: ffffffff85a1e007 R11: fffffbfff0b43c00 R12: ffff88810eaaaf58 [ 225.945757] R13: 0000000000000000 R14: ffff88810eaaafb8 R15: ffff88815897f040 [ 225.946709] FS: 00007ff3f2505080(0000) GS:ffff888fb5e00000(0000) knlGS:0000000000000000 [ 225.947814] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 225.948556] CR2: ffffffffffffffd6 CR3: 000000015aa5a006 CR4: 0000000000370ee0 [ 225.949537] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 225.950455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 225.951414] Call Trace: [ 225.951787] [ 225.952120] mempool_alloc+0xe5/0x250 [ 225.952625] ? mempool_resize+0x370/0x370 [ 225.953187] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.953862] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.954464] ? sched_clock_cpu+0x15/0x120 [ 225.955019] ? find_held_lock+0xac/0xd0 [ 225.955564] bio_alloc_bioset+0x1ed/0x2a0 [ 225.956080] ? lock_downgrade+0x3a0/0x3a0 [ 225.956644] ? bvec_alloc+0xc0/0xc0 [ 225.957135] bio_clone_fast+0x19/0x80 [ 225.957651] raid5_make_request+0x1370/0x1b70 [ 225.958286] ? sched_clock_cpu+0x15/0x120 [ 225.958797] ? __lock_acquire+0x8b2/0x3510 [ 225.959339] ? raid5_get_active_stripe+0xce0/0xce0 [ 225.959986] ? lock_is_held_type+0xd8/0x130 [ 225.960528] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.961135] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.961703] ? sched_clock_cpu+0x15/0x120 [ 225.962232] ? lock_release+0x27a/0x6c0 [ 225.962746] ? do_wait_intr_irq+0x130/0x130 [ 225.963302] ? lock_downgrade+0x3a0/0x3a0 [ 225.963815] ? lock_release+0x6c0/0x6c0 [ 225.964348] md_handle_request+0x342/0x530 [ 225.964888] ? set_in_sync+0x170/0x170 [ 225.965397] ? blk_queue_split+0x133/0x150 [ 225.965988] ? __blk_queue_split+0x8b0/0x8b0 [ 225.966524] ? submit_bio_checks+0x3b2/0x9d0 [ 225.967069] md_submit_bio+0x127/0x1c0 [...] Fix this by moving alloc/free of acct bioset to pers->run and pers->free. While we are on this, properly handle md_integrity_register() error in raid0_run(). Fixes: daee2024715d (md: check level before create and exit io_acct_set) Cc: stable@vger.kernel.org Acked-by: Guoqing Jiang Signed-off-by: Xiao Ni Signed-off-by: Song Liu --- drivers/md/raid0.c | 38 ++++++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 10 deletions(-) (limited to 'drivers/md/raid0.c') diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 62c8b6adac70..b59a77b31b90 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -356,7 +356,21 @@ static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks return array_sectors; } -static void raid0_free(struct mddev *mddev, void *priv); +static void free_conf(struct mddev *mddev, struct r0conf *conf) +{ + kfree(conf->strip_zone); + kfree(conf->devlist); + kfree(conf); + mddev->private = NULL; +} + +static void raid0_free(struct mddev *mddev, void *priv) +{ + struct r0conf *conf = priv; + + free_conf(mddev, conf); + acct_bioset_exit(mddev); +} static int raid0_run(struct mddev *mddev) { @@ -370,11 +384,16 @@ static int raid0_run(struct mddev *mddev) if (md_check_no_bitmap(mddev)) return -EINVAL; + if (acct_bioset_init(mddev)) { + pr_err("md/raid0:%s: alloc acct bioset failed.\n", mdname(mddev)); + return -ENOMEM; + } + /* if private is not null, we are here after takeover */ if (mddev->private == NULL) { ret = create_strip_zones(mddev, &conf); if (ret < 0) - return ret; + goto exit_acct_set; mddev->private = conf; } conf = mddev->private; @@ -413,17 +432,16 @@ static int raid0_run(struct mddev *mddev) dump_zones(mddev); ret = md_integrity_register(mddev); + if (ret) + goto free; return ret; -} -static void raid0_free(struct mddev *mddev, void *priv) -{ - struct r0conf *conf = priv; - - kfree(conf->strip_zone); - kfree(conf->devlist); - kfree(conf); +free: + free_conf(mddev, conf); +exit_acct_set: + acct_bioset_exit(mddev); + return ret; } static void raid0_handle_discard(struct mddev *mddev, struct bio *bio) -- cgit