From: syzbot <syzbot+f9d847b2b84164fa69f3@syzkaller.appspotmail.com>
To: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com,
kuba@kernel.org, linux-input@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
netdev@vger.kernel.org, pabeni@redhat.com,
syzkaller-bugs@googlegroups.com
Subject: [syzbot] [net?] [input?] [usb?] memory leak in ldisc_receive
Date: Sat, 17 Jan 2026 09:34:23 -0800 [thread overview]
Message-ID: <696bc81f.050a0220.3390f1.000f.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: b71e635feefc Merge tag 'cgroup-for-6.19-rc5-fixes' of git:..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1638a59a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=87bc41cae23d2144
dashboard link: https://syzkaller.appspot.com/bug?extid=f9d847b2b84164fa69f3
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=162985fc580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1035f922580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/821cfcb36509/disk-b71e635f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/80f2b6f81538/vmlinux-b71e635f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5a9299bca98/bzImage-b71e635f.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f9d847b2b84164fa69f3@syzkaller.appspotmail.com
BUG: memory leak
unreferenced object 0xffff888109d88b00 (size 240):
comm "syz.0.17", pid 6088, jiffies 4294942822
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 20 8e 13 81 88 ff ff 00 00 00 00 00 00 00 00 . ..............
backtrace (crc cd2b8445):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x384/0x5a0 mm/slub.c:5315
__alloc_skb+0xe8/0x2b0 net/core/skbuff.c:679
__netdev_alloc_skb+0x72/0x230 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
ldisc_receive+0x7d/0x210 drivers/net/caif/caif_serial.c:176
tiocsti drivers/tty/tty_io.c:2290 [inline]
tty_ioctl+0x329/0xd40 drivers/tty/tty_io.c:2706
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+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88810a368500 (size 240):
comm "syz.0.18", pid 6193, jiffies 4294942941
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 20 94 13 81 88 ff ff 00 00 00 00 00 00 00 00 . ..............
backtrace (crc 5d1300cb):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x384/0x5a0 mm/slub.c:5315
__alloc_skb+0xe8/0x2b0 net/core/skbuff.c:679
__netdev_alloc_skb+0x72/0x230 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
ldisc_receive+0x7d/0x210 drivers/net/caif/caif_serial.c:176
tiocsti drivers/tty/tty_io.c:2290 [inline]
tty_ioctl+0x329/0xd40 drivers/tty/tty_io.c:2706
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+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88810a9e2c00 (size 704):
comm "syz.0.18", pid 6193, jiffies 4294942941
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 b6200c):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x384/0x5a0 mm/slub.c:5315
kmalloc_reserve+0xe6/0x180 net/core/skbuff.c:586
__alloc_skb+0x111/0x2b0 net/core/skbuff.c:690
__netdev_alloc_skb+0x72/0x230 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
ldisc_receive+0x7d/0x210 drivers/net/caif/caif_serial.c:176
tiocsti drivers/tty/tty_io.c:2290 [inline]
tty_ioctl+0x329/0xd40 drivers/tty/tty_io.c:2706
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+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888109ddda00 (size 240):
comm "syz.0.19", pid 6262, jiffies 4294943059
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 50 8e 13 81 88 ff ff 00 00 00 00 00 00 00 00 .P..............
backtrace (crc 3f6ba7c1):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x384/0x5a0 mm/slub.c:5315
__alloc_skb+0xe8/0x2b0 net/core/skbuff.c:679
__netdev_alloc_skb+0x72/0x230 net/core/skbuff.c:754
netdev_alloc_skb include/linux/skbuff.h:3484 [inline]
ldisc_receive+0x7d/0x210 drivers/net/caif/caif_serial.c:176
tiocsti drivers/tty/tty_io.c:2290 [inline]
tty_ioctl+0x329/0xd40 drivers/tty/tty_io.c:2706
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+0xa4/0xf80 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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reply other threads:[~2026-01-17 17:34 UTC|newest]
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