micropython #5
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…l/git/netfilter/nf Florisn Westphal says: ==================== These are netfilter fixes for the *net* tree. First patch resolves a false-positive lockdep splat: rcu_dereference is used outside of rcu read lock. Let lockdep validate that the transaction mutex is locked. Second patch fixes a kdoc warning added in previous PR. Third patch fixes a memory leak: The catchall element isn't disabled correctly, this allows userspace to deactivate the element again. This results in refcount underflow which in turn prevents memory release. This was always broken since the feature was added in 5.13. Patch 4 fixes an incorrect change in the previous pull request: Adding a duplicate key to a set should work if the duplicate key has expired, restore this behaviour. All from myself. Patch #5 resolves an old historic artifact in sctp conntrack: a 300ms timeout for shutdown_ack. Increase this to 3s. From Xin Long. Patch #6 fixes a sysctl data race in ipvs, two threads can clobber the sysctl value, from Sishuai Gong. This is a day-0 bug that predates git history. Patches 7, 8 and 9, from Pablo Neira Ayuso, are also followups for the previous GC rework in nf_tables: The netlink notifier and the netns exit path must both increment the gc worker seqcount, else worker may encounter stale (free'd) pointers. ================ Signed-off-by: David S. Miller <davem@davemloft.net>
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unix_tot_inflight is changed under spin_lock(unix_gc_lock), but unix_release_sock() reads it locklessly. Let's use READ_ONCE() for unix_tot_inflight. Note that the writer side was marked by commit 9d6d7f1 ("af_unix: annote lockless accesses to unix_tot_inflight & gc_in_progress") BUG: KCSAN: data-race in unix_inflight / unix_release_sock write (marked) to 0xffffffff871852b8 of 4 bytes by task 123 on cpu 1: unix_inflight+0x130/0x180 net/unix/scm.c:64 unix_attach_fds+0x137/0x1b0 net/unix/scm.c:123 unix_scm_to_skb net/unix/af_unix.c:1832 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1955 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0x148/0x160 net/socket.c:747 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2493 ___sys_sendmsg+0xc6/0x140 net/socket.c:2547 __sys_sendmsg+0x94/0x140 net/socket.c:2576 __do_sys_sendmsg net/socket.c:2585 [inline] __se_sys_sendmsg net/socket.c:2583 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2583 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc read to 0xffffffff871852b8 of 4 bytes by task 4891 on cpu 0: unix_release_sock+0x608/0x910 net/unix/af_unix.c:671 unix_release+0x59/0x80 net/unix/af_unix.c:1058 __sock_release+0x7d/0x170 net/socket.c:653 sock_close+0x19/0x30 net/socket.c:1385 __fput+0x179/0x5e0 fs/file_table.c:321 ____fput+0x15/0x20 fs/file_table.c:349 task_work_run+0x116/0x1a0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc value changed: 0x00000000 -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 4891 Comm: systemd-coredum Not tainted 6.4.0-rc5-01219-gfa0e21fa4443 #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 9305cfa ("[AF_UNIX]: Make unix_tot_inflight counter non-atomic") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Sebastian Andrzej Siewior says: ==================== net: hsr: Properly parse HSRv1 supervisor frames. this is a follow-up to https://lore.kernel.org/all/20230825153111.228768-1-lukma@denx.de/ replacing https://lore.kernel.org/all/20230914124731.1654059-1-lukma@denx.de/ by grabing/ adding tags and reposting with a commit message plus a missing __packed to a struct (#2) plus extending the testsuite to sover HSRv1 which is what broke here (#3-#5). HSRv0 is (was) not affected. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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If CONFIG_HARDENED_USERCOPY is enabled, copying completion record from event log cache to user triggers a kernel bug. [ 1987.159822] usercopy: Kernel memory exposure attempt detected from SLUB object 'dsa0' (offset 74, size 31)! [ 1987.170845] ------------[ cut here ]------------ [ 1987.176086] kernel BUG at mm/usercopy.c:102! [ 1987.180946] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 1987.186866] CPU: 17 PID: 528 Comm: kworker/17:1 Not tainted 6.8.0-rc2+ #5 [ 1987.194537] Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023 [ 1987.206405] Workqueue: wq0.0 idxd_evl_fault_work [idxd] [ 1987.212338] RIP: 0010:usercopy_abort+0x72/0x90 [ 1987.217381] Code: 58 65 9c 50 48 c7 c2 17 85 61 9c 57 48 c7 c7 98 fd 6b 9c 48 0f 44 d6 48 c7 c6 b3 08 62 9c 4c 89 d1 49 0f 44 f3 e8 1e 2e d5 ff <0f> 0b 49 c7 c1 9e 42 61 9c 4c 89 cf 4d 89 c8 eb a9 66 66 2e 0f 1f [ 1987.238505] RSP: 0018:ff62f5cf20607d60 EFLAGS: 00010246 [ 1987.244423] RAX: 000000000000005f RBX: 000000000000001f RCX: 0000000000000000 [ 1987.252480] RDX: 0000000000000000 RSI: ffffffff9c61429e RDI: 00000000ffffffff [ 1987.260538] RBP: ff62f5cf20607d78 R08: ff2a6a89ef3fffe8 R09: 00000000fffeffff [ 1987.268595] R10: ff2a6a89eed00000 R11: 0000000000000003 R12: ff2a66934849c89a [ 1987.276652] R13: 0000000000000001 R14: ff2a66934849c8b9 R15: ff2a66934849c899 [ 1987.284710] FS: 0000000000000000(0000) GS:ff2a66b22fe40000(0000) knlGS:0000000000000000 [ 1987.293850] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1987.300355] CR2: 00007fe291a37000 CR3: 000000010fbd4005 CR4: 0000000000f71ef0 [ 1987.308413] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1987.316470] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 1987.324527] PKRU: 55555554 [ 1987.327622] Call Trace: [ 1987.330424] <TASK> [ 1987.332826] ? show_regs+0x6e/0x80 [ 1987.336703] ? die+0x3c/0xa0 [ 1987.339988] ? do_trap+0xd4/0xf0 [ 1987.343662] ? do_error_trap+0x75/0xa0 [ 1987.347922] ? usercopy_abort+0x72/0x90 [ 1987.352277] ? exc_invalid_op+0x57/0x80 [ 1987.356634] ? usercopy_abort+0x72/0x90 [ 1987.360988] ? asm_exc_invalid_op+0x1f/0x30 [ 1987.365734] ? usercopy_abort+0x72/0x90 [ 1987.370088] __check_heap_object+0xb7/0xd0 [ 1987.374739] __check_object_size+0x175/0x2d0 [ 1987.379588] idxd_copy_cr+0xa9/0x130 [idxd] [ 1987.384341] idxd_evl_fault_work+0x127/0x390 [idxd] [ 1987.389878] process_one_work+0x13e/0x300 [ 1987.394435] ? __pfx_worker_thread+0x10/0x10 [ 1987.399284] worker_thread+0x2f7/0x420 [ 1987.403544] ? _raw_spin_unlock_irqrestore+0x2b/0x50 [ 1987.409171] ? __pfx_worker_thread+0x10/0x10 [ 1987.414019] kthread+0x107/0x140 [ 1987.417693] ? __pfx_kthread+0x10/0x10 [ 1987.421954] ret_from_fork+0x3d/0x60 [ 1987.426019] ? __pfx_kthread+0x10/0x10 [ 1987.430281] ret_from_fork_asm+0x1b/0x30 [ 1987.434744] </TASK> The issue arises because event log cache is created using kmem_cache_create() which is not suitable for user copy. Fix the issue by creating event log cache with kmem_cache_create_usercopy(), ensuring safe user copy. Fixes: c2f156b ("dmaengine: idxd: create kmem cache for event log fault items") Reported-by: Tony Zhu <tony.zhu@intel.com> Tested-by: Tony Zhu <tony.zhu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Lijun Pan <lijun.pan@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240209191412.1050270-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
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…pty list
If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.
Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.
It can be reproduced by a small script like:
echo "Setting config..."
ip link add dev wg0 type wireguard
wg setconf wg0 /big-config
(
while true; do
echo "Showing config..."
wg showconf wg0 > /dev/null
done
) &
sleep 4
wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")
Resulting in:
BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
Read of size 8 at addr ffff88811956ec70 by task wg/59
CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5
Call Trace:
<TASK>
dump_stack_lvl+0x47/0x70
print_address_description.constprop.0+0x2c/0x380
print_report+0xab/0x250
kasan_report+0xba/0xf0
__lock_acquire+0x182a/0x1b20
lock_acquire+0x191/0x4b0
down_read+0x80/0x440
get_peer+0x140/0xcb0
wg_get_device_dump+0x471/0x1130
Cc: stable@vger.kernel.org
Fixes: e7096c1 ("net: WireGuard secure network tunnel")
Reported-by: Lillian Berry <lillian@star-ark.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Its used from trace__run(), for the 'perf trace' live mode, i.e. its
strace-like, non-perf.data file processing mode, the most common one.
The trace__run() function will set trace->host using machine__new_host()
that is supposed to give a machine instance representing the running
machine, and since we'll use perf_env__arch_strerrno() to get the right
errno -> string table, we need to use machine->env, so initialize it in
machine__new_host().
Before the patch:
(gdb) run trace --errno-summary -a sleep 1
<SNIP>
Summary of events:
gvfs-afc-volume (3187), 2 events, 0.0%
syscall calls errors total min avg max stddev
(msec) (msec) (msec) (msec) (%)
--------------- -------- ------ -------- --------- --------- --------- ------
pselect6 1 0 0.000 0.000 0.000 0.000 0.00%
GUsbEventThread (3519), 2 events, 0.0%
syscall calls errors total min avg max stddev
(msec) (msec) (msec) (msec) (%)
--------------- -------- ------ -------- --------- --------- --------- ------
poll 1 0 0.000 0.000 0.000 0.000 0.00%
<SNIP>
Program received signal SIGSEGV, Segmentation fault.
0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
478 if (env->arch_strerrno == NULL)
(gdb) bt
#0 0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
#1 0x00000000004b75d2 in thread__dump_stats (ttrace=0x14f58f0, trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4673
#2 0x00000000004b78bf in trace__fprintf_thread (fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>, thread=0x10fa0b0, trace=0x7fffffffa5b0) at builtin-trace.c:4708
#3 0x00000000004b7ad9 in trace__fprintf_thread_summary (trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4747
#4 0x00000000004b656e in trace__run (trace=0x7fffffffa5b0, argc=2, argv=0x7fffffffde60) at builtin-trace.c:4456
#5 0x00000000004ba43e in cmd_trace (argc=2, argv=0x7fffffffde60) at builtin-trace.c:5487
#6 0x00000000004c0414 in run_builtin (p=0xec3068 <commands+648>, argc=5, argv=0x7fffffffde60) at perf.c:351
#7 0x00000000004c06bb in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:404
#8 0x00000000004c0814 in run_argv (argcp=0x7fffffffdc4c, argv=0x7fffffffdc40) at perf.c:448
torvalds#9 0x00000000004c0b5d in main (argc=5, argv=0x7fffffffde60) at perf.c:560
(gdb)
After:
root@number:~# perf trace -a --errno-summary sleep 1
<SNIP>
pw-data-loop (2685), 1410 events, 16.0%
syscall calls errors total min avg max stddev
(msec) (msec) (msec) (msec) (%)
--------------- -------- ------ -------- --------- --------- --------- ------
epoll_wait 188 0 983.428 0.000 5.231 15.595 8.68%
ioctl 94 0 0.811 0.004 0.009 0.016 2.82%
read 188 0 0.322 0.001 0.002 0.006 5.15%
write 141 0 0.280 0.001 0.002 0.018 8.39%
timerfd_settime 94 0 0.138 0.001 0.001 0.007 6.47%
gnome-control-c (179406), 1848 events, 20.9%
syscall calls errors total min avg max stddev
(msec) (msec) (msec) (msec) (%)
--------------- -------- ------ -------- --------- --------- --------- ------
poll 222 0 959.577 0.000 4.322 21.414 11.40%
recvmsg 150 0 0.539 0.001 0.004 0.013 5.12%
write 300 0 0.442 0.001 0.001 0.007 3.29%
read 150 0 0.183 0.001 0.001 0.009 5.53%
getpid 102 0 0.101 0.000 0.001 0.008 7.82%
root@number:~#
Fixes: 54373b5 ("perf env: Introduce perf_env__arch_strerrno()")
Reported-by: Veronika Molnarova <vmolnaro@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Veronika Molnarova <vmolnaro@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Michael Petlan <mpetlan@redhat.com>
Link: https://lore.kernel.org/r/Z0XffUgNSv_9OjOi@x1
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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…s_lock For storing a value to a queue attribute, the queue_attr_store function first freezes the queue (->q_usage_counter(io)) and then acquire ->sysfs_lock. This seems not correct as the usual ordering should be to acquire ->sysfs_lock before freezing the queue. This incorrect ordering causes the following lockdep splat which we are able to reproduce always simply by accessing /sys/kernel/debug file using ls command: [ 57.597146] WARNING: possible circular locking dependency detected [ 57.597154] 6.12.0-10553-gb86545e02e8c torvalds#20 Tainted: G W [ 57.597162] ------------------------------------------------------ [ 57.597168] ls/4605 is trying to acquire lock: [ 57.597176] c00000003eb56710 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0x58/0xc0 [ 57.597200] but task is already holding lock: [ 57.597207] c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4 [ 57.597226] which lock already depends on the new lock. [ 57.597233] the existing dependency chain (in reverse order) is: [ 57.597241] -> #5 (&sb->s_type->i_mutex_key#3){++++}-{4:4}: [ 57.597255] down_write+0x6c/0x18c [ 57.597264] start_creating+0xb4/0x24c [ 57.597274] debugfs_create_dir+0x2c/0x1e8 [ 57.597283] blk_register_queue+0xec/0x294 [ 57.597292] add_disk_fwnode+0x2e4/0x548 [ 57.597302] brd_alloc+0x2c8/0x338 [ 57.597309] brd_init+0x100/0x178 [ 57.597317] do_one_initcall+0x88/0x3e4 [ 57.597326] kernel_init_freeable+0x3cc/0x6e0 [ 57.597334] kernel_init+0x34/0x1cc [ 57.597342] ret_from_kernel_user_thread+0x14/0x1c [ 57.597350] -> #4 (&q->debugfs_mutex){+.+.}-{4:4}: [ 57.597362] __mutex_lock+0xfc/0x12a0 [ 57.597370] blk_register_queue+0xd4/0x294 [ 57.597379] add_disk_fwnode+0x2e4/0x548 [ 57.597388] brd_alloc+0x2c8/0x338 [ 57.597395] brd_init+0x100/0x178 [ 57.597402] do_one_initcall+0x88/0x3e4 [ 57.597410] kernel_init_freeable+0x3cc/0x6e0 [ 57.597418] kernel_init+0x34/0x1cc [ 57.597426] ret_from_kernel_user_thread+0x14/0x1c [ 57.597434] -> #3 (&q->sysfs_lock){+.+.}-{4:4}: [ 57.597446] __mutex_lock+0xfc/0x12a0 [ 57.597454] queue_attr_store+0x9c/0x110 [ 57.597462] sysfs_kf_write+0x70/0xb0 [ 57.597471] kernfs_fop_write_iter+0x1b0/0x2ac [ 57.597480] vfs_write+0x3dc/0x6e8 [ 57.597488] ksys_write+0x84/0x140 [ 57.597495] system_call_exception+0x130/0x360 [ 57.597504] system_call_common+0x160/0x2c4 [ 57.597516] -> #2 (&q->q_usage_counter(io)torvalds#21){++++}-{0:0}: [ 57.597530] __submit_bio+0x5ec/0x828 [ 57.597538] submit_bio_noacct_nocheck+0x1e4/0x4f0 [ 57.597547] iomap_readahead+0x2a0/0x448 [ 57.597556] xfs_vm_readahead+0x28/0x3c [ 57.597564] read_pages+0x88/0x41c [ 57.597571] page_cache_ra_unbounded+0x1ac/0x2d8 [ 57.597580] filemap_get_pages+0x188/0x984 [ 57.597588] filemap_read+0x13c/0x4bc [ 57.597596] xfs_file_buffered_read+0x88/0x17c [ 57.597605] xfs_file_read_iter+0xac/0x158 [ 57.597614] vfs_read+0x2d4/0x3b4 [ 57.597622] ksys_read+0x84/0x144 [ 57.597629] system_call_exception+0x130/0x360 [ 57.597637] system_call_common+0x160/0x2c4 [ 57.597647] -> #1 (mapping.invalidate_lock#2){++++}-{4:4}: [ 57.597661] down_read+0x6c/0x220 [ 57.597669] filemap_fault+0x870/0x100c [ 57.597677] xfs_filemap_fault+0xc4/0x18c [ 57.597684] __do_fault+0x64/0x164 [ 57.597693] __handle_mm_fault+0x1274/0x1dac [ 57.597702] handle_mm_fault+0x248/0x484 [ 57.597711] ___do_page_fault+0x428/0xc0c [ 57.597719] hash__do_page_fault+0x30/0x68 [ 57.597727] do_hash_fault+0x90/0x35c [ 57.597736] data_access_common_virt+0x210/0x220 [ 57.597745] _copy_from_user+0xf8/0x19c [ 57.597754] sel_write_load+0x178/0xd54 [ 57.597762] vfs_write+0x108/0x6e8 [ 57.597769] ksys_write+0x84/0x140 [ 57.597777] system_call_exception+0x130/0x360 [ 57.597785] system_call_common+0x160/0x2c4 [ 57.597794] -> #0 (&mm->mmap_lock){++++}-{4:4}: [ 57.597806] __lock_acquire+0x17cc/0x2330 [ 57.597814] lock_acquire+0x138/0x400 [ 57.597822] __might_fault+0x7c/0xc0 [ 57.597830] filldir64+0xe8/0x390 [ 57.597839] dcache_readdir+0x80/0x2d4 [ 57.597846] iterate_dir+0xd8/0x1d4 [ 57.597855] sys_getdents64+0x88/0x2d4 [ 57.597864] system_call_exception+0x130/0x360 [ 57.597872] system_call_common+0x160/0x2c4 [ 57.597881] other info that might help us debug this: [ 57.597888] Chain exists of: &mm->mmap_lock --> &q->debugfs_mutex --> &sb->s_type->i_mutex_key#3 [ 57.597905] Possible unsafe locking scenario: [ 57.597911] CPU0 CPU1 [ 57.597917] ---- ---- [ 57.597922] rlock(&sb->s_type->i_mutex_key#3); [ 57.597932] lock(&q->debugfs_mutex); [ 57.597940] lock(&sb->s_type->i_mutex_key#3); [ 57.597950] rlock(&mm->mmap_lock); [ 57.597958] *** DEADLOCK *** [ 57.597965] 2 locks held by ls/4605: [ 57.597971] #0: c0000000137c12f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0xcc/0x154 [ 57.597989] #1: c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4 Prevent the above lockdep warning by acquiring ->sysfs_lock before freezing the queue while storing a queue attribute in queue_attr_store function. Later, we also found[1] another function __blk_mq_update_nr_ hw_queues where we first freeze queue and then acquire the ->sysfs_lock. So we've also updated lock ordering in __blk_mq_update_nr_hw_queues function and ensured that in all code paths we follow the correct lock ordering i.e. acquire ->sysfs_lock before freezing the queue. [1] https://lore.kernel.org/all/CAFj5m9Ke8+EHKQBs_Nk6hqd=LGXtk4mUxZUN5==ZcCjnZSBwHw@mail.gmail.com/ Reported-by: kjain@linux.ibm.com Fixes: af28141 ("block: freeze the queue in queue_attr_store") Tested-by: kjain@linux.ibm.com Cc: hch@lst.de Cc: axboe@kernel.dk Cc: ritesh.list@gmail.com Cc: ming.lei@redhat.com Cc: gjoyce@linux.ibm.com Signed-off-by: Nilay Shroff <nilay@linux.ibm.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241210144222.1066229-1-nilay@linux.ibm.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Feb 7, 2025
When testing the atomic write fix patches, the f2fs_bug_on was triggered as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/inode.c:935! Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 3 UID: 0 PID: 257 Comm: bash Not tainted 6.13.0-rc1-00033-gc283a70d3497 #5 RIP: 0010:f2fs_evict_inode+0x50f/0x520 Call Trace: <TASK> ? __die_body+0x65/0xb0 ? die+0x9f/0xc0 ? do_trap+0xa1/0x170 ? f2fs_evict_inode+0x50f/0x520 ? f2fs_evict_inode+0x50f/0x520 ? handle_invalid_op+0x65/0x80 ? f2fs_evict_inode+0x50f/0x520 ? exc_invalid_op+0x39/0x50 ? asm_exc_invalid_op+0x1a/0x20 ? __pfx_f2fs_get_dquots+0x10/0x10 ? f2fs_evict_inode+0x50f/0x520 ? f2fs_evict_inode+0x2e5/0x520 evict+0x186/0x2f0 prune_icache_sb+0x75/0xb0 super_cache_scan+0x1a8/0x200 do_shrink_slab+0x163/0x320 shrink_slab+0x2fc/0x470 drop_slab+0x82/0xf0 drop_caches_sysctl_handler+0x4e/0xb0 proc_sys_call_handler+0x183/0x280 vfs_write+0x36d/0x450 ksys_write+0x68/0xd0 do_syscall_64+0xc8/0x1a0 ? arch_exit_to_user_mode_prepare+0x11/0x60 ? irqentry_exit_to_user_mode+0x7e/0xa0 The root cause is: f2fs uses FI_ATOMIC_DIRTIED to indicate dirty atomic files during commit. If the inode is dirtied during commit, such as by f2fs_i_pino_write, the vfs inode keeps clean and the f2fs inode is set to FI_DIRTY_INODE. The FI_DIRTY_INODE flag cann't be cleared by write_inode later due to the clean vfs inode. Finally, f2fs_bug_on is triggered due to this inconsistent state when evict. To reproduce this situation: - fd = open("/mnt/test.db", O_WRONLY) - ioctl(fd, F2FS_IOC_START_ATOMIC_WRITE) - mv /mnt/test.db /mnt/test1.db - ioctl(fd, F2FS_IOC_COMMIT_ATOMIC_WRITE) - echo 3 > /proc/sys/vm/drop_caches To fix this problem, clear FI_DIRTY_INODE after commit, then f2fs_mark_inode_dirty_sync will ensure a consistent dirty state. Fixes: fccaa81 ("f2fs: prevent atomic file from being dirtied before commit") Signed-off-by: Yunlei He <heyunlei@xiaomi.com> Signed-off-by: Jianan Huang <huangjianan@xiaomi.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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libtraceevent parses and returns an array of argument fields, sometimes
larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr",
idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6
elements max, creating an out-of-bounds access. This runtime error is
found by UBsan. The error message:
$ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1
builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]'
#0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966
#1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110
#2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436
#3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897
#4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335
#5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502
#6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351
#7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404
#8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448
torvalds#9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556
torvalds#10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
torvalds#11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360
torvalds#12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6)
0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1) = 1
Fixes: 5e58fcf ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint")
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
neuschaefer
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This fixes the following hard lockup in isolate_lru_folios() during memory reclaim. If the LRU mostly contains ineligible folios this may trigger watchdog. watchdog: Watchdog detected hard LOCKUP on cpu 173 RIP: 0010:native_queued_spin_lock_slowpath+0x255/0x2a0 Call Trace: _raw_spin_lock_irqsave+0x31/0x40 folio_lruvec_lock_irqsave+0x5f/0x90 folio_batch_move_lru+0x91/0x150 lru_add_drain_per_cpu+0x1c/0x40 process_one_work+0x17d/0x350 worker_thread+0x27b/0x3a0 kthread+0xe8/0x120 ret_from_fork+0x34/0x50 ret_from_fork_asm+0x1b/0x30 lruvec->lru_lock owner： PID: 2865 TASK: ffff888139214d40 CPU: 40 COMMAND: "kswapd0" #0 [fffffe0000945e60] crash_nmi_callback at ffffffffa567a555 #1 [fffffe0000945e68] nmi_handle at ffffffffa563b171 #2 [fffffe0000945eb0] default_do_nmi at ffffffffa6575920 #3 [fffffe0000945ed0] exc_nmi at ffffffffa6575af4 #4 [fffffe0000945ef0] end_repeat_nmi at ffffffffa6601dde [exception RIP: isolate_lru_folios+403] RIP: ffffffffa597df53 RSP: ffffc90006fb7c28 RFLAGS: 00000002 RAX: 0000000000000001 RBX: ffffc90006fb7c60 RCX: ffffea04a2196f88 RDX: ffffc90006fb7c60 RSI: ffffc90006fb7c60 RDI: ffffea04a2197048 RBP: ffff88812cbd3010 R8: ffffea04a2197008 R9: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: ffffea04a2197008 R13: ffffea04a2197048 R14: ffffc90006fb7de8 R15: 0000000003e3e937 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 <NMI exception stack> #5 [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53 #6 [ffffc90006fb7cf8] shrink_active_list at ffffffffa597f788 #7 [ffffc90006fb7da8] balance_pgdat at ffffffffa5986db0 #8 [ffffc90006fb7ec0] kswapd at ffffffffa5987354 torvalds#9 [ffffc90006fb7ef8] kthread at ffffffffa5748238 crash> Scenario: User processe are requesting a large amount of memory and keep page active. Then a module continuously requests memory from ZONE_DMA32 area. Memory reclaim will be triggered due to ZONE_DMA32 watermark alarm reached. However pages in the LRU(active_anon) list are mostly from the ZONE_NORMAL area. Reproduce: Terminal 1: Construct to continuously increase pages active(anon). mkdir /tmp/memory mount -t tmpfs -o size=1024000M tmpfs /tmp/memory dd if=/dev/zero of=/tmp/memory/block bs=4M tail /tmp/memory/block Terminal 2: vmstat -a 1 active will increase. procs ---memory--- ---swap-- ---io---- -system-- ---cpu--- ... r b swpd free inact active si so bi bo 1 0 0 1445623076 45898836 83646008 0 0 0 1 0 0 1445623076 43450228 86094616 0 0 0 1 0 0 1445623076 41003480 88541364 0 0 0 1 0 0 1445623076 38557088 90987756 0 0 0 1 0 0 1445623076 36109688 93435156 0 0 0 1 0 0 1445619552 33663256 95881632 0 0 0 1 0 0 1445619804 31217140 98327792 0 0 0 1 0 0 1445619804 28769988 100774944 0 0 0 1 0 0 1445619804 26322348 103222584 0 0 0 1 0 0 1445619804 23875592 105669340 0 0 0 cat /proc/meminfo | head Active(anon) increase. MemTotal: 1579941036 kB MemFree: 1445618500 kB MemAvailable: 1453013224 kB Buffers: 6516 kB Cached: 128653956 kB SwapCached: 0 kB Active: 118110812 kB Inactive: 11436620 kB Active(anon): 115345744 kB Inactive(anon): 945292 kB When the Active(anon) is 115345744 kB, insmod module triggers the ZONE_DMA32 watermark. perf record -e vmscan:mm_vmscan_lru_isolate -aR perf script isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=2 nr_skipped=2 nr_taken=0 lru=active_anon isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=0 nr_skipped=0 nr_taken=0 lru=active_anon isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=28835844 nr_skipped=28835844 nr_taken=0 lru=active_anon isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=28835844 nr_skipped=28835844 nr_taken=0 lru=active_anon isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=29 nr_skipped=29 nr_taken=0 lru=active_anon isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=0 nr_skipped=0 nr_taken=0 lru=active_anon See nr_scanned=28835844. 28835844 * 4k = 115343376KB approximately equal to 115345744 kB. If increase Active(anon) to 1000G then insmod module triggers the ZONE_DMA32 watermark. hard lockup will occur. In my device nr_scanned = 0000000003e3e937 when hard lockup. Convert to memory size 0x0000000003e3e937 * 4KB = 261072092 KB. [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53 ffffc90006fb7c30: 0000000000000020 0000000000000000 ffffc90006fb7c40: ffffc90006fb7d40 ffff88812cbd3000 ffffc90006fb7c50: ffffc90006fb7d30 0000000106fb7de8 ffffc90006fb7c60: ffffea04a2197008 ffffea0006ed4a48 ffffc90006fb7c70: 0000000000000000 0000000000000000 ffffc90006fb7c80: 0000000000000000 0000000000000000 ffffc90006fb7c90: 0000000000000000 0000000000000000 ffffc90006fb7ca0: 0000000000000000 0000000003e3e937 ffffc90006fb7cb0: 0000000000000000 0000000000000000 ffffc90006fb7cc0: 8d7c0b56b7874b00 ffff88812cbd3000 About the Fixes: Why did it take eight years to be discovered? The problem requires the following conditions to occur: 1. The device memory should be large enough. 2. Pages in the LRU(active_anon) list are mostly from the ZONE_NORMAL area. 3. The memory in ZONE_DMA32 needs to reach the watermark. If the memory is not large enough, or if the usage design of ZONE_DMA32 area memory is reasonable, this problem is difficult to detect. notes: The problem is most likely to occur in ZONE_DMA32 and ZONE_NORMAL, but other suitable scenarios may also trigger the problem. Link: https://lkml.kernel.org/r/20241119060842.274072-1-liuye@kylinos.cn Fixes: b2e1875 ("mm, vmscan: begin reclaiming pages on a per-node basis") Signed-off-by: liuye <liuye@kylinos.cn> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Yang Shi <yang@os.amperecomputing.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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-z textto gcc flags on buildroot+muslcrash
The issue is a
.textrelocation:The problematic snippet can simply be replaced by
b nlr_push_tail.The text was updated successfully, but these errors were encountered: