From: Greg Kroah-Hartman Date: Mon, 25 Apr 2022 08:53:30 +0000 (+0200) Subject: 5.10-stable patches X-Git-Tag: v4.9.312~55 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=17724fa2b74f5f0d70a849fd8e2ce11f7471018a;p=thirdparty%2Fkernel%2Fstable-queue.git 5.10-stable patches added patches: dm-fix-mempool-null-pointer-race-when-completing-io.patch --- diff --git a/queue-5.10/dm-fix-mempool-null-pointer-race-when-completing-io.patch b/queue-5.10/dm-fix-mempool-null-pointer-race-when-completing-io.patch new file mode 100644 index 00000000000..8bbf937273e --- /dev/null +++ b/queue-5.10/dm-fix-mempool-null-pointer-race-when-completing-io.patch @@ -0,0 +1,140 @@ +From d208b89401e073de986dc891037c5a668f5d5d95 Mon Sep 17 00:00:00 2001 +From: Jiazi Li +Date: Wed, 29 Sep 2021 19:59:28 +0800 +Subject: dm: fix mempool NULL pointer race when completing IO + +From: Jiazi Li + +commit d208b89401e073de986dc891037c5a668f5d5d95 upstream. + +dm_io_dec_pending() calls end_io_acct() first and will then dec md +in-flight pending count. But if a task is swapping DM table at same +time this can result in a crash due to mempool->elements being NULL: + +task1 task2 +do_resume + ->do_suspend + ->dm_wait_for_completion + bio_endio + ->clone_endio + ->dm_io_dec_pending + ->end_io_acct + ->wakeup task1 + ->dm_swap_table + ->__bind + ->__bind_mempools + ->bioset_exit + ->mempool_exit + ->free_io + +[ 67.330330] Unable to handle kernel NULL pointer dereference at +virtual address 0000000000000000 +...... +[ 67.330494] pstate: 80400085 (Nzcv daIf +PAN -UAO) +[ 67.330510] pc : mempool_free+0x70/0xa0 +[ 67.330515] lr : mempool_free+0x4c/0xa0 +[ 67.330520] sp : ffffff8008013b20 +[ 67.330524] x29: ffffff8008013b20 x28: 0000000000000004 +[ 67.330530] x27: ffffffa8c2ff40a0 x26: 00000000ffff1cc8 +[ 67.330535] x25: 0000000000000000 x24: ffffffdada34c800 +[ 67.330541] x23: 0000000000000000 x22: ffffffdada34c800 +[ 67.330547] x21: 00000000ffff1cc8 x20: ffffffd9a1304d80 +[ 67.330552] x19: ffffffdada34c970 x18: 000000b312625d9c +[ 67.330558] x17: 00000000002dcfbf x16: 00000000000006dd +[ 67.330563] x15: 000000000093b41e x14: 0000000000000010 +[ 67.330569] x13: 0000000000007f7a x12: 0000000034155555 +[ 67.330574] x11: 0000000000000001 x10: 0000000000000001 +[ 67.330579] x9 : 0000000000000000 x8 : 0000000000000000 +[ 67.330585] x7 : 0000000000000000 x6 : ffffff80148b5c1a +[ 67.330590] x5 : ffffff8008013ae0 x4 : 0000000000000001 +[ 67.330596] x3 : ffffff80080139c8 x2 : ffffff801083bab8 +[ 67.330601] x1 : 0000000000000000 x0 : ffffffdada34c970 +[ 67.330609] Call trace: +[ 67.330616] mempool_free+0x70/0xa0 +[ 67.330627] bio_put+0xf8/0x110 +[ 67.330638] dec_pending+0x13c/0x230 +[ 67.330644] clone_endio+0x90/0x180 +[ 67.330649] bio_endio+0x198/0x1b8 +[ 67.330655] dec_pending+0x190/0x230 +[ 67.330660] clone_endio+0x90/0x180 +[ 67.330665] bio_endio+0x198/0x1b8 +[ 67.330673] blk_update_request+0x214/0x428 +[ 67.330683] scsi_end_request+0x2c/0x300 +[ 67.330688] scsi_io_completion+0xa0/0x710 +[ 67.330695] scsi_finish_command+0xd8/0x110 +[ 67.330700] scsi_softirq_done+0x114/0x148 +[ 67.330708] blk_done_softirq+0x74/0xd0 +[ 67.330716] __do_softirq+0x18c/0x374 +[ 67.330724] irq_exit+0xb4/0xb8 +[ 67.330732] __handle_domain_irq+0x84/0xc0 +[ 67.330737] gic_handle_irq+0x148/0x1b0 +[ 67.330744] el1_irq+0xe8/0x190 +[ 67.330753] lpm_cpuidle_enter+0x4f8/0x538 +[ 67.330759] cpuidle_enter_state+0x1fc/0x398 +[ 67.330764] cpuidle_enter+0x18/0x20 +[ 67.330772] do_idle+0x1b4/0x290 +[ 67.330778] cpu_startup_entry+0x20/0x28 +[ 67.330786] secondary_start_kernel+0x160/0x170 + +Fix this by: +1) Establishing pointers to 'struct dm_io' members in +dm_io_dec_pending() so that they may be passed into end_io_acct() +_after_ free_io() is called. +2) Moving end_io_acct() after free_io(). + +Cc: stable@vger.kernel.org +Signed-off-by: Jiazi Li +Signed-off-by: Mike Snitzer +Signed-off-by: Akilesh Kailash +Signed-off-by: Greg Kroah-Hartman +--- + drivers/md/dm.c | 17 ++++++++++------- + 1 file changed, 10 insertions(+), 7 deletions(-) + +--- a/drivers/md/dm.c ++++ b/drivers/md/dm.c +@@ -607,18 +607,17 @@ static void start_io_acct(struct dm_io * + false, 0, &io->stats_aux); + } + +-static void end_io_acct(struct dm_io *io) ++static void end_io_acct(struct mapped_device *md, struct bio *bio, ++ unsigned long start_time, struct dm_stats_aux *stats_aux) + { +- struct mapped_device *md = io->md; +- struct bio *bio = io->orig_bio; +- unsigned long duration = jiffies - io->start_time; ++ unsigned long duration = jiffies - start_time; + +- bio_end_io_acct(bio, io->start_time); ++ bio_end_io_acct(bio, start_time); + + if (unlikely(dm_stats_used(&md->stats))) + dm_stats_account_io(&md->stats, bio_data_dir(bio), + bio->bi_iter.bi_sector, bio_sectors(bio), +- true, duration, &io->stats_aux); ++ true, duration, stats_aux); + + /* nudge anyone waiting on suspend queue */ + if (unlikely(wq_has_sleeper(&md->wait))) +@@ -903,6 +902,8 @@ static void dec_pending(struct dm_io *io + blk_status_t io_error; + struct bio *bio; + struct mapped_device *md = io->md; ++ unsigned long start_time = 0; ++ struct dm_stats_aux stats_aux; + + /* Push-back supersedes any I/O errors */ + if (unlikely(error)) { +@@ -929,8 +930,10 @@ static void dec_pending(struct dm_io *io + + io_error = io->status; + bio = io->orig_bio; +- end_io_acct(io); ++ start_time = io->start_time; ++ stats_aux = io->stats_aux; + free_io(md, io); ++ end_io_acct(md, bio, start_time, &stats_aux); + + if (io_error == BLK_STS_DM_REQUEUE) + return; diff --git a/queue-5.10/series b/queue-5.10/series index 359fa6c8f9c..2cbf6d96cde 100644 --- a/queue-5.10/series +++ b/queue-5.10/series @@ -6,3 +6,4 @@ gfs2-assign-rgrp-glock-before-compute_bitstructs.patch net-sched-cls_u32-fix-netns-refcount-changes-in-u32_change.patch alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch alsa-hda-realtek-add-quirk-for-clevo-np70pnp.patch +dm-fix-mempool-null-pointer-race-when-completing-io.patch