[syzbot] [comedi?] memory leak in do_cmd_ioctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8f0b4cce4481 Linux 6.19-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17df89b4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d60836e327fd6756
dashboard link: https://syzkaller.appspot.com/bug?extid=f238baf6ded841b5a82e
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=10bad11a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17d0411a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6b3f098aba85/disk-8f0b4cce.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e249c8a4ce76/vmlinux-8f0b4cce.xz
kernel image: https://storage.googleapis.com/syzbot-assets/851cb7eb2c27/bzImage-8f0b4cce.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f238ba...@syzkaller.appspotmail.com

BUG: memory leak
unreferenced object 0xffff88811193c4d8 (size 8):
comm "syz.0.17", pid 6094, jiffies 4294942826
hex dump (first 8 bytes):
04 00 00 00 00 00 00 00 ........
backtrace (crc 844a0efa):
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]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_node_track_caller_noprof+0x3af/0x670 mm/slub.c:5764
memdup_user+0x2a/0xe0 mm/util.c:221
memdup_array_user include/linux/string.h:39 [inline]
__comedi_get_user_chanlist drivers/comedi/comedi_fops.c:1815 [inline]
do_cmd_ioctl.part.0+0x112/0x350 drivers/comedi/comedi_fops.c:1890
do_cmd_ioctl drivers/comedi/comedi_fops.c:1858 [inline]
comedi_unlocked_ioctl+0xdea/0x1300 drivers/comedi/comedi_fops.c:2319
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 0xffff88811193c990 (size 8):
comm "syz.0.18", pid 6096, jiffies 4294942827
hex dump (first 8 bytes):
04 00 00 00 00 00 00 00 ........
backtrace (crc 844a0efa):
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]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_node_track_caller_noprof+0x3af/0x670 mm/slub.c:5764
memdup_user+0x2a/0xe0 mm/util.c:221
memdup_array_user include/linux/string.h:39 [inline]
__comedi_get_user_chanlist drivers/comedi/comedi_fops.c:1815 [inline]
do_cmd_ioctl.part.0+0x112/0x350 drivers/comedi/comedi_fops.c:1890
do_cmd_ioctl drivers/comedi/comedi_fops.c:1858 [inline]
comedi_unlocked_ioctl+0xdea/0x1300 drivers/comedi/comedi_fops.c:2319
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 0xffff88811193cea0 (size 8):
comm "syz.0.19", pid 6099, jiffies 4294942829
hex dump (first 8 bytes):
04 00 00 00 00 00 00 00 ........
backtrace (crc 844a0efa):
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]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_node_track_caller_noprof+0x3af/0x670 mm/slub.c:5764
memdup_user+0x2a/0xe0 mm/util.c:221
memdup_array_user include/linux/string.h:39 [inline]
__comedi_get_user_chanlist drivers/comedi/comedi_fops.c:1815 [inline]
do_cmd_ioctl.part.0+0x112/0x350 drivers/comedi/comedi_fops.c:1890
do_cmd_ioctl drivers/comedi/comedi_fops.c:1858 [inline]
comedi_unlocked_ioctl+0xdea/0x1300 drivers/comedi/comedi_fops.c:2319
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 0xffff888144d28bf8 (size 8):
comm "syz.0.20", pid 6124, jiffies 4294943361
hex dump (first 8 bytes):
04 00 00 00 00 00 00 00 ........
backtrace (crc 844a0efa):
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]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_node_track_caller_noprof+0x3af/0x670 mm/slub.c:5764
memdup_user+0x2a/0xe0 mm/util.c:221
memdup_array_user include/linux/string.h:39 [inline]
__comedi_get_user_chanlist drivers/comedi/comedi_fops.c:1815 [inline]
do_cmd_ioctl.part.0+0x112/0x350 drivers/comedi/comedi_fops.c:1890
do_cmd_ioctl drivers/comedi/comedi_fops.c:1858 [inline]
comedi_unlocked_ioctl+0xdea/0x1300 drivers/comedi/comedi_fops.c:2319
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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