[syzbot] [net?] [input?] [usb?] memory leak in ldisc_receive
From: syzbot <hidden>
Date: 2026-01-17 17:34:24
Also in:
linux-input, linux-usb, lkml
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 --- This report is generated by a bot. 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