public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+cae7809e9dc1459e4e63@syzkaller.appspotmail.com>
To: dxdt@dev.snart.me, linux-kernel@vger.kernel.org,
	 syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [mm?] [exfat?] [f2fs?] memory leak in __kfree_rcu_sheaf
Date: Sat, 02 May 2026 05:02:01 -0700	[thread overview]
Message-ID: <69f5e7b9.050a0220.312cd3.0022.GAE@google.com> (raw)
In-Reply-To: <ffd7be2b-8da4-45bd-b8a3-881855815bc6@dev.snart.me>

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
memory leak in __pcs_replace_empty_main

BUG: memory leak
unreferenced object 0xffff88810005f600 (size 512):
  comm "swapper/0", pid 0, jiffies 4294937296
  hex dump (first 32 bytes):
    00 3c e7 2c 81 88 ff ff 00 4c 90 00 81 88 ff ff  .<.,.....L......
    00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00  ........<.......
  backtrace (crc 37d70d29):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_empty_main+0x22a/0x2a0 mm/slub.c:4646
    alloc_from_pcs mm/slub.c:4749 [inline]
    slab_alloc_node mm/slub.c:4883 [inline]
    __kmalloc_cache_noprof+0x3a6/0x480 mm/slub.c:5410
    kmalloc_noprof include/linux/slab.h:950 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __irq_domain_alloc_fwnode+0x37/0x140 kernel/irq/irqdomain.c:95
    irq_domain_alloc_named_fwnode include/linux/irqdomain.h:271 [inline]
    arch_early_irq_init+0x1c/0x70 arch/x86/kernel/apic/vector.c:803
    start_kernel+0x931/0xb80 init/main.c:1123
    x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
    x86_64_start_kernel+0xce/0xd0 arch/x86/kernel/head64.c:291
    common_startup_64+0x13e/0x148

BUG: memory leak
unreferenced object 0xffff888100904c00 (size 512):
  comm "kthreadd", pid 2, jiffies 4294937342
  hex dump (first 32 bytes):
    00 f6 05 00 81 88 ff ff 00 ea 3c 04 81 88 ff ff  ..........<.....
    00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00  ........<.......
  backtrace (crc 22dd8c01):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_empty_main+0x22a/0x2a0 mm/slub.c:4646
    alloc_from_pcs mm/slub.c:4749 [inline]
    slab_alloc_node mm/slub.c:4883 [inline]
    __kmalloc_cache_node_noprof+0x3e9/0x4d0 mm/slub.c:5423
    kmalloc_node_noprof include/linux/slab.h:1077 [inline]
    __get_vm_area_node+0xc6/0x1d0 mm/vmalloc.c:3215
    __vmalloc_node_range_noprof+0x1bc/0xdf0 mm/vmalloc.c:4024
    __vmalloc_node_noprof+0x71/0x90 mm/vmalloc.c:4124
    alloc_thread_stack_node kernel/fork.c:357 [inline]
    dup_task_struct kernel/fork.c:926 [inline]
    copy_process+0x51f/0x2c90 kernel/fork.c:2090
    kernel_clone+0xde/0x700 kernel/fork.c:2721
    kernel_thread+0x80/0xb0 kernel/fork.c:2782
    create_kthread kernel/kthread.c:459 [inline]
    kthreadd+0x186/0x250 kernel/kthread.c:817
    ret_from_fork+0x219/0x490 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff88810224cc00 (size 512):
  comm "kworker/1:1", pid 41, jiffies 4294937440
  hex dump (first 32 bytes):
    00 18 fd 2c 81 88 ff ff 00 e8 3c 04 81 88 ff ff  ...,......<.....
    00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00  ........<.......
  backtrace (crc 254b2b5e):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_full_main+0xdf/0x300 mm/slub.c:5757
    free_to_pcs mm/slub.c:5810 [inline]
    slab_free mm/slub.c:6249 [inline]
    kfree+0x361/0x3a0 mm/slub.c:6561
    vfree mm/vmalloc.c:3476 [inline]
    vfree+0x14d/0x3d0 mm/vmalloc.c:3436
    delayed_vfree_work+0x29/0x40 mm/vmalloc.c:3392
    process_one_work+0x277/0x5b0 kernel/workqueue.c:3302
    process_scheduled_works kernel/workqueue.c:3385 [inline]
    worker_thread+0x255/0x4a0 kernel/workqueue.c:3466
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x219/0x490 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff8881043cea00 (size 512):
  comm "kworker/0:1", pid 10, jiffies 4294937496
  hex dump (first 32 bytes):
    00 4c 90 00 81 88 ff ff 00 4a 73 11 81 88 ff ff  .L.......Js.....
    00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00  ........<.......
  backtrace (crc c256e00a):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_full_main+0xdf/0x300 mm/slub.c:5757
    free_to_pcs mm/slub.c:5810 [inline]
    slab_free mm/slub.c:6249 [inline]
    kfree+0x361/0x3a0 mm/slub.c:6561
    blk_free_flush_queue+0x28/0x40 block/blk-flush.c:514
    srcu_invoke_callbacks+0x11a/0x1c0 kernel/rcu/srcutree.c:1917
    process_one_work+0x277/0x5b0 kernel/workqueue.c:3302
    process_scheduled_works kernel/workqueue.c:3385 [inline]
    worker_thread+0x255/0x4a0 kernel/workqueue.c:3466
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x219/0x490 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff8881043ce800 (size 512):
  comm "kworker/0:1", pid 10, jiffies 4294937496
  hex dump (first 32 bytes):
    00 cc 24 02 81 88 ff ff 00 d4 48 0b 81 88 ff ff  ..$.......H.....
    00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00  ........<.......
  backtrace (crc 98e15bd5):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_full_main+0xdf/0x300 mm/slub.c:5757
    free_to_pcs mm/slub.c:5810 [inline]
    slab_free mm/slub.c:6249 [inline]
    kfree+0x361/0x3a0 mm/slub.c:6561
    vfree mm/vmalloc.c:3476 [inline]
    vfree+0x14d/0x3d0 mm/vmalloc.c:3436
    delayed_vfree_work+0x29/0x40 mm/vmalloc.c:3392
    process_one_work+0x277/0x5b0 kernel/workqueue.c:3302
    process_scheduled_works kernel/workqueue.c:3385 [inline]
    worker_thread+0x255/0x4a0 kernel/workqueue.c:3466
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x219/0x490 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff88810b41a600 (size 512):
  comm "udevadm", pid 4977, jiffies 4294938322
  hex dump (first 32 bytes):
    00 cc 48 0b 81 88 ff ff 00 7e 23 28 81 88 ff ff  ..H......~#(....
    00 12 04 00 81 88 ff ff 00 00 00 00 00 00 00 00  ................
  backtrace (crc ccf4ae11):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4574 [inline]
    slab_alloc_node mm/slub.c:4898 [inline]
    __do_kmalloc_node mm/slub.c:5294 [inline]
    __kmalloc_noprof+0x3b7/0x550 mm/slub.c:5307
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    __alloc_empty_sheaf+0x35/0x50 mm/slub.c:2768
    alloc_empty_sheaf mm/slub.c:2783 [inline]
    __pcs_replace_empty_main+0x22a/0x2a0 mm/slub.c:4646
    alloc_from_pcs mm/slub.c:4749 [inline]
    slab_alloc_node mm/slub.c:4883 [inline]
    __kmalloc_cache_noprof+0x3a6/0x480 mm/slub.c:5410
    kmalloc_noprof include/linux/slab.h:950 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    kernfs_get_open_node fs/kernfs/file.c:543 [inline]
    kernfs_fop_open+0x4f4/0x580 fs/kernfs/file.c:718
    do_dentry_open+0x1fc/0x8c0 fs/open.c:947
    vfs_open+0x3d/0x1b0 fs/open.c:1079
    do_open fs/namei.c:4699 [inline]
    path_openat+0x154d/0x1e20 fs/namei.c:4858
    do_file_open+0x121/0x200 fs/namei.c:4887
    do_sys_openat2+0xa5/0x140 fs/open.c:1364
    do_sys_open fs/open.c:1370 [inline]
    __do_sys_openat fs/open.c:1386 [inline]
    __se_sys_openat fs/open.c:1381 [inline]
    __x64_sys_openat+0x82/0xf0 fs/open.c:1381
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xee/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF


Tested on:

commit:         f1a5e78a Merge tag 'drm-fixes-2026-05-02' of https://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10bff5ba580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9645c21cfd1d3e8f
dashboard link: https://syzkaller.appspot.com/bug?extid=cae7809e9dc1459e4e63
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
patch:          https://syzkaller.appspot.com/x/patch.diff?x=13270a36580000


       reply	other threads:[~2026-05-02 12:02 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <ffd7be2b-8da4-45bd-b8a3-881855815bc6@dev.snart.me>
2026-05-02 12:02 ` syzbot [this message]
2026-05-03  6:00 [syzbot] [mm?] [f2fs?] [exfat?] memory leak in __kfree_rcu_sheaf David Timber
2026-05-03  7:17 ` [syzbot] [mm?] [exfat?] [f2fs?] " syzbot
  -- strict thread matches above, loose matches on Subject: below --
2026-05-03  6:05 [syzbot] [mm?] [f2fs?] [exfat?] " David Timber
2026-05-03  7:27 ` [syzbot] [mm?] [exfat?] [f2fs?] " syzbot
2026-05-03  7:41   ` David Timber
2026-05-04 20:17 [syzbot] [mm?] [f2fs?] [exfat?] " David Timber
2026-05-04 20:51 ` [syzbot] [mm?] [exfat?] [f2fs?] " syzbot
2026-05-04 20:26 [syzbot] [mm?] [f2fs?] [exfat?] " David Timber
2026-05-04 21:12 ` [syzbot] [mm?] [exfat?] [f2fs?] " syzbot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=69f5e7b9.050a0220.312cd3.0022.GAE@google.com \
    --to=syzbot+cae7809e9dc1459e4e63@syzkaller.appspotmail.com \
    --cc=dxdt@dev.snart.me \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox