[syzbot] [bluetooth?] memory leak in init_srcu_struct_fields

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f377d0025eb0 Merge tag 'sh-for-v7.1-tag2' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1737bb48580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9645c21cfd1d3e8f
dashboard link: https://syzkaller.appspot.com/bug?extid=535ecc844591e50588a5
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=164ed748580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10e6576c580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5d8163677f58/disk-f377d002.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cf2fcdb8200b/vmlinux-f377d002.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e9fb70799318/bzImage-f377d002.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+535ecc...@syzkaller.appspotmail.com

BUG: memory leak
unreferenced object 0xffff888111f49600 (size 512):
comm "syz.0.17", pid 5937, jiffies 4294945495
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 6e7d3fde):
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]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5414
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
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

BUG: memory leak
unreferenced object (percpu) 0x607e4d93d800 (size 384):
comm "syz.0.17", pid 5937, jiffies 4294945495
hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
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

BUG: memory leak
unreferenced object (percpu) 0x607e4d93d980 (size 384):
comm "syz.0.18", pid 5940, jiffies 4294945497
hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
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

BUG: memory leak
unreferenced object 0xffff88811d010a00 (size 512):
comm "syz.0.19", pid 5951, jiffies 4294945502
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 2d3d1dd8):
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]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5414
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
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

BUG: memory leak
unreferenced object (percpu) 0x607e4d93db00 (size 384):
comm "syz.0.19", pid 5951, jiffies 4294945502
hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
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


---
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[syzbot]

For archival purposes, forwarding an incoming command email to
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***

Subject: [PATCH] Bluetooth: hci_core: Fix SRCU leak when device is freed unregistered
Author: karti...@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master


hci_alloc_dev_priv() initializes hdev->srcu with init_srcu_struct(), but
the matching cleanup_srcu_struct() is only called from hci_unregister_dev().
A hci_dev that is allocated and then freed without ever being registered
leaks the SRCU internals - the node array and the per-CPU sda - even though
the hci_dev itself is freed correctly.

This is reachable from the hci_uart line discipline. h5_open() (used by the
HCI_UART_3WIRE protocol) sets HCI_UART_INIT_PENDING, so hci_uart_register_dev()
returns early without calling hci_register_dev() and HCI_UART_REGISTERED is
never set. Registration is deferred until the three-wire link is synced, which
never happens over a bare pty. When the tty is closed, hci_uart_tty_close()
finds HCI_UART_REGISTERED clear, skips hci_unregister_dev(), and calls
hci_free_dev() -> hci_release_dev() -> kfree(hdev), orphaning the SRCU
allocations.

kmemleak reports only the SRCU sub-objects, not hdev, confirming that hdev is
freed while its embedded srcu is not torn down:

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774

Pair the SRCU init with destruction by calling cleanup_srcu_struct() from
hci_release_dev(), so it runs on the final put_device() regardless of whether
the device was ever registered. Keep synchronize_srcu() in hci_unregister_dev()
to drain readers walking the device list before the device leaves it.

Reported-by: syzbot+535ecc...@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=535ecc844591e50588a5
Signed-off-by: Deepanshu Kartikey <karti...@gmail.com>
---
net/bluetooth/hci_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 28d7929dc593..2d516beedb59 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2664,7 +2664,6 @@ void hci_unregister_dev(struct hci_dev *hdev)
write_unlock(&hci_dev_list_lock);

synchronize_srcu(&hdev->srcu);
- cleanup_srcu_struct(&hdev->srcu);

disable_work_sync(&hdev->rx_work);
disable_work_sync(&hdev->cmd_work);
@@ -2737,6 +2736,8 @@ void hci_release_dev(struct hci_dev *hdev)
kfree_skb(hdev->sent_cmd);
kfree_skb(hdev->req_skb);
kfree_skb(hdev->recv_event);
+
+ cleanup_srcu_struct(&hdev->srcu);
kfree(hdev);
}
EXPORT_SYMBOL(hci_release_dev);
--
2.43.0

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

Subject: [PATCH] Bluetooth: hci_core: Fix SRCU leak when device is freed unregistered
Author: karti...@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master



hci_alloc_dev_priv() initializes hdev->srcu with init_srcu_struct(), but
the matching cleanup_srcu_struct() is only called from hci_unregister_dev().
A hci_dev that is allocated and then freed without ever being registered
leaks the SRCU internals - the node array and the per-CPU sda - even though
the hci_dev itself is freed correctly.

This is reachable from the hci_uart line discipline. h5_open() (used by the
HCI_UART_3WIRE protocol) sets HCI_UART_INIT_PENDING, so hci_uart_register_dev()
returns early without calling hci_register_dev() and HCI_UART_REGISTERED is
never set. Registration is deferred until the three-wire link is synced, which
never happens over a bare pty. When the tty is closed, hci_uart_tty_close()
finds HCI_UART_REGISTERED clear, skips hci_unregister_dev(), and calls
hci_free_dev() -> hci_release_dev() -> kfree(hdev), orphaning the SRCU
allocations.

kmemleak reports only the SRCU sub-objects, not hdev, confirming that hdev is
freed while its embedded srcu is not torn down:

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774

[syzbot]

Hello,

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

BUG: memory leak
unreferenced object 0xffff88810de6f800 (size 512):
comm "syz.0.17", pid 6610, jiffies 4294948707

hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace (crc 55438727):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4613 [inline]
slab_alloc_node mm/slub.c:4937 [inline]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5443
_kmalloc_noprof include/linux/slab.h:969 [inline]
_kzalloc_noprof include/linux/slab.h:1286 [inline]
init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806

tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]

do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object (percpu) 0x607e4db7f740 (size 384):
comm "syz.0.17", pid 6610, jiffies 4294948707

hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806

tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]

do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object (percpu) 0x607e4db7f8c0 (size 384):
comm "syz.0.18", pid 6619, jiffies 4294948711

hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806

tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]

do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object (percpu) 0x607e4db7fa40 (size 384):
comm "syz.0.19", pid 6624, jiffies 4294948716

hex dump (first 32 bytes on cpu 0):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806

tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]

do_syscall_64+0xee/0x600 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: 7da7f071 Add linux-next specific files for 20260529
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14bf17a6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3dd1e35bbd92239d

dashboard link: https://syzkaller.appspot.com/bug?extid=535ecc844591e50588a5
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=10cd7ed2580000

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

Subject: [PATCH] Bluetooth: hci_core: Fix SRCU leak when device is freed unregistered
Author: karti...@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

hci_alloc_dev_priv() initializes hdev->srcu with init_srcu_struct(), but
the matching cleanup_srcu_struct() is only called from hci_unregister_dev().
A hci_dev that is allocated and then freed without ever being registered
leaks the SRCU internals - the node array and the per-CPU sda - even though
the hci_dev itself is freed correctly.

This is reachable from the hci_uart line discipline. h5_open() (used by the
HCI_UART_3WIRE protocol) sets HCI_UART_INIT_PENDING, so hci_uart_register_dev()
returns early without calling hci_register_dev() and HCI_UART_REGISTERED is
never set. Registration is deferred until the three-wire link is synced, which
never happens over a bare pty. When the tty is closed, hci_uart_tty_close()
finds HCI_UART_REGISTERED clear, skips hci_unregister_dev(), and calls
hci_free_dev() -> hci_release_dev() -> kfree(hdev), orphaning the SRCU
allocations.

kmemleak reports only the SRCU sub-objects, not hdev, confirming that hdev is
freed while its embedded srcu is not torn down:

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2453
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:644 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:720 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:774

[syzbot]

Hello,

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

BUG: memory leak

unreferenced object (percpu) 0x607e4db7f7c0 (size 384):
comm "syz.0.17", pid 6615, jiffies 4294948617
hex dump (first 32 bytes on cpu 1):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416

hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]

hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object 0xffff88810de8e800 (size 512):
comm "syz.0.18", pid 6621, jiffies 4294948621

hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace (crc 4c023471):

kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4613 [inline]
slab_alloc_node mm/slub.c:4937 [inline]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5443
_kmalloc_noprof include/linux/slab.h:969 [inline]
_kzalloc_noprof include/linux/slab.h:1286 [inline]

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]

hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object (percpu) 0x607e4db7f940 (size 384):
comm "syz.0.18", pid 6621, jiffies 4294948621
hex dump (first 32 bytes on cpu 1):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416

hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]

hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object 0xffff88810de8fc00 (size 512):
comm "syz.0.19", pid 6630, jiffies 4294948624

hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace (crc a013f5be):

kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4613 [inline]
slab_alloc_node mm/slub.c:4937 [inline]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5443
_kmalloc_noprof include/linux/slab.h:969 [inline]
_kzalloc_noprof include/linux/slab.h:1286 [inline]

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]

hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object (percpu) 0x607e4db7fac0 (size 384):
comm "syz.0.19", pid 6630, jiffies 4294948624
hex dump (first 32 bytes on cpu 1):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):
pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1956
init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416

hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]

hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 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: 7da7f071 Add linux-next specific files for 20260529
git tree: linux-next

console output: https://syzkaller.appspot.com/x/log.txt?x=1395b36a580000

kernel config: https://syzkaller.appspot.com/x/.config?x=3dd1e35bbd92239d
dashboard link: https://syzkaller.appspot.com/bug?extid=535ecc844591e50588a5
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=123de056580000

[syzbot]

Hello,

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

BUG: memory leak

unreferenced object 0xffff88810ace7000 (size 512):
comm "syz.0.17", pid 6583, jiffies 4294948651

hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace (crc 1a69216d):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4575 [inline]
slab_alloc_node mm/slub.c:4899 [inline]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5415
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object (percpu) 0x607e4d944640 (size 384):
comm "syz.0.17", pid 6583, jiffies 4294948651
hex dump (first 32 bytes on cpu 0):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896

init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object 0xffff88810b1d9200 (size 512):
comm "syz.0.18", pid 6587, jiffies 4294948653

hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace (crc 27fa06af):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4575 [inline]
slab_alloc_node mm/slub.c:4899 [inline]
__kmalloc_cache_noprof+0x371/0x480 mm/slub.c:5415
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]

init_srcu_struct_fields+0x2c0/0x350 kernel/rcu/srcutree.c:207
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object (percpu) 0x607e4d9447c0 (size 384):
comm "syz.0.18", pid 6587, jiffies 4294948653
hex dump (first 32 bytes on cpu 0):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896

init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak

unreferenced object (percpu) 0x607e4d944980 (size 384):
comm "syz.0.19", pid 6595, jiffies 4294948657
hex dump (first 32 bytes on cpu 0):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 593bdea7):

pcpu_alloc_noprof+0x7c7/0xed0 mm/percpu.c:1896

init_srcu_struct_fields+0x2eb/0x350 kernel/rcu/srcutree.c:224
hci_alloc_dev_priv+0x37/0x680 net/bluetooth/hci_core.c:2416
hci_alloc_dev include/net/bluetooth/hci_core.h:1763 [inline]
hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:672 [inline]
hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:752 [inline]
hci_uart_tty_ioctl+0x173/0x460 drivers/bluetooth/hci_ldisc.c:806
tty_ioctl+0xaca/0xd60 drivers/tty/tty_io.c:2801
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0xf4/0x140 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xee/0x600 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: 174914ea Merge tag 'v7.1-rc6-smb3-client-fixes' of git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17f2f57e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5733044df9370cfc

dashboard link: https://syzkaller.appspot.com/bug?extid=535ecc844591e50588a5
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=17b2f57e580000