Re: [syzbot] [mm?] [f2fs?] [exfat?] memory leak in __kfree_rcu_sheaf

syzbot
2026-03-18T03:08:04Z

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 0xffff88810e983c00 (size 512):
comm "softirq", pid 0, jiffies 4294948614
hex dump (first 32 bytes):
c8 2c 04 00 81 88 ff ff 00 a4 98 0e 81 88 ff ff .,..............
00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00 ........<.......
backtrace (crc 8f5c2bf9):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4543 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x3bd/0x560 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
__alloc_empty_sheaf+0x35/0x50 mm/slub.c:2764
alloc_empty_sheaf mm/slub.c:2779 [inline]
alloc_full_sheaf mm/slub.c:2829 [inline]
__pcs_replace_empty_main+0x1e0/0x2f0 mm/slub.c:4626
alloc_from_pcs mm/slub.c:4717 [inline]
slab_alloc_node mm/slub.c:4851 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x4c5/0x560 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
cfg80211_inform_single_bss_data+0x21d/0xa70 net/wireless/scan.c:2344
cfg80211_inform_bss_data+0x13f/0x1dc0 net/wireless/scan.c:3226
cfg80211_inform_bss_frame_data+0x108/0x340 net/wireless/scan.c:3317
ieee80211_bss_info_update+0x13a/0x320 net/mac80211/scan.c:230
ieee80211_scan_rx+0x269/0x3b0 net/mac80211/scan.c:364
__ieee80211_rx_handle_packet net/mac80211/rx.c:5305 [inline]
ieee80211_rx_list+0x111b/0x1850 net/mac80211/rx.c:5588
ieee80211_rx_napi+0x50/0x110 net/mac80211/rx.c:5611
ieee80211_rx include/net/mac80211.h:5267 [inline]
ieee80211_handle_queued_frames+0x9c/0xf0 net/mac80211/main.c:452
tasklet_action_common+0xb7/0x270 kernel/softirq.c:925
handle_softirqs+0xdf/0x2c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x91/0xb0 kernel/softirq.c:723
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x73/0x80 arch/x86/kernel/apic/apic.c:1056

BUG: memory leak
unreferenced object 0xffff88810e98a400 (size 512):
comm "kworker/u8:7", pid 1022, jiffies 4294952987
hex dump (first 32 bytes):
00 3c 98 0e 81 88 ff ff 00 68 cd 2a 81 88 ff ff .<.......h.*....
00 12 04 00 81 88 ff ff 3c 00 00 00 00 00 00 00 ........<.......
backtrace (crc b6e2f12f):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4543 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x3bd/0x560 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
__alloc_empty_sheaf+0x35/0x50 mm/slub.c:2764
alloc_empty_sheaf mm/slub.c:2779 [inline]
alloc_full_sheaf mm/slub.c:2829 [inline]
__pcs_replace_empty_main+0x1e0/0x2f0 mm/slub.c:4626
alloc_from_pcs mm/slub.c:4717 [inline]
slab_alloc_node mm/slub.c:4851 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x4c5/0x560 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
cfg80211_inform_single_bss_data+0x21d/0xa70 net/wireless/scan.c:2344
cfg80211_inform_bss_data+0x13f/0x1dc0 net/wireless/scan.c:3226
cfg80211_inform_bss_frame_data+0x108/0x340 net/wireless/scan.c:3317
ieee80211_bss_info_update+0x13a/0x320 net/mac80211/scan.c:230
ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline]
ieee80211_ibss_rx_queued_mgmt+0xb75/0x1230 net/mac80211/ibss.c:1602
ieee80211_iface_process_skb net/mac80211/iface.c:1748 [inline]
ieee80211_iface_work+0x6af/0x9b0 net/mac80211/iface.c:1802
cfg80211_wiphy_work+0x1db/0x280 net/wireless/core.c:440
process_one_work+0x277/0x5f0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x255/0x4a0 kernel/workqueue.c:3440
kthread+0x14e/0x1a0 kernel/kthread.c:436
ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

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

Tested on:

commit: a989fde7 Merge tag 'libnvdimm-fixes-7.0-rc5' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1005f8da580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e2bba615ee79faa5
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=1405b406580000