Re: [syzbot] [usb?] memory leak in es58x_open

Oliver Neukum
2026-01-12T15:06:17Z

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#syz test: upstream ea1013c15392

On 22.12.25 06:27, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: ea1013c15392 Merge tag 'bpf-fixes' of git://git.kernel.org..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1607bdc2580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=d60836e327fd6756
> dashboard link: https://syzkaller.appspot.com/bug?extid=e8cb6691a7cf68256cb8
> 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=131add92580000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/5ee91238d53c/disk-ea1013c1.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/b8eb70b8203f/vmlinux-ea1013c1.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/3aed81c1b1c5/bzImage-ea1013c1.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+e8cb6691a7cf68256cb8@syzkaller.appspotmail.com
>
> BUG: memory leak
> unreferenced object 0xffff88812623e000 (size 512):
> comm "dhcpcd", pid 5478, jiffies 4294946142
> 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 0):
> 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_noprof+0x3e0/0x660 mm/slub.c:5669
> kmalloc_noprof include/linux/slab.h:961 [inline]
> hcd_buffer_alloc+0x151/0x190 drivers/usb/core/buffer.c:134
> usb_alloc_coherent+0x44/0x70 drivers/usb/core/usb.c:1010
> es58x_alloc_urb+0x4c/0xc0 drivers/net/can/usb/etas_es58x/es58x_core.c:1553
> es58x_alloc_rx_urbs drivers/net/can/usb/etas_es58x/es58x_core.c:1711 [inline]
> es58x_open+0x1b3/0x470 drivers/net/can/usb/etas_es58x/es58x_core.c:1785
> __dev_open+0x1be/0x3c0 net/core/dev.c:1683
> __dev_change_flags+0x30c/0x380 net/core/dev.c:9734
> netif_change_flags+0x35/0x90 net/core/dev.c:9797
> dev_change_flags+0x64/0xf0 net/core/dev_api.c:68
> devinet_ioctl+0x5bf/0xd30 net/ipv4/devinet.c:1199
> inet_ioctl+0x27c/0x2b0 net/ipv4/af_inet.c:1009
> sock_do_ioctl+0x84/0x1a0 net/socket.c:1254
> sock_ioctl+0x149/0x480 net/socket.c:1375
> 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 0xffff888126112200 (size 512):
> comm "dhcpcd", pid 5478, jiffies 4294946373
> 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 0):
> 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_noprof+0x3e0/0x660 mm/slub.c:5669
> kmalloc_noprof include/linux/slab.h:961 [inline]
> hcd_buffer_alloc+0x151/0x190 drivers/usb/core/buffer.c:134
> usb_alloc_coherent+0x44/0x70 drivers/usb/core/usb.c:1010
> es58x_alloc_urb+0x4c/0xc0 drivers/net/can/usb/etas_es58x/es58x_core.c:1553
> es58x_alloc_rx_urbs drivers/net/can/usb/etas_es58x/es58x_core.c:1711 [inline]
> es58x_open+0x1b3/0x470 drivers/net/can/usb/etas_es58x/es58x_core.c:1785
> __dev_open+0x1be/0x3c0 net/core/dev.c:1683
> __dev_change_flags+0x30c/0x380 net/core/dev.c:9734
> netif_change_flags+0x35/0x90 net/core/dev.c:9797
> dev_change_flags+0x64/0xf0 net/core/dev_api.c:68
> devinet_ioctl+0x5bf/0xd30 net/ipv4/devinet.c:1199
> inet_ioctl+0x27c/0x2b0 net/ipv4/af_inet.c:1009
> sock_do_ioctl+0x84/0x1a0 net/socket.c:1254
> sock_ioctl+0x149/0x480 net/socket.c:1375
> 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 0xffff888126188800 (size 512):
> comm "dhcpcd", pid 5478, jiffies 4294946404
> 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 0):
> 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_noprof+0x3e0/0x660 mm/slub.c:5669
> kmalloc_noprof include/linux/slab.h:961 [inline]
> hcd_buffer_alloc+0x151/0x190 drivers/usb/core/buffer.c:134
> usb_alloc_coherent+0x44/0x70 drivers/usb/core/usb.c:1010
> es58x_alloc_urb+0x4c/0xc0 drivers/net/can/usb/etas_es58x/es58x_core.c:1553
> es58x_alloc_rx_urbs drivers/net/can/usb/etas_es58x/es58x_core.c:1711 [inline]
> es58x_open+0x1b3/0x470 drivers/net/can/usb/etas_es58x/es58x_core.c:1785
> __dev_open+0x1be/0x3c0 net/core/dev.c:1683
> __dev_change_flags+0x30c/0x380 net/core/dev.c:9734
> netif_change_flags+0x35/0x90 net/core/dev.c:9797
> dev_change_flags+0x64/0xf0 net/core/dev_api.c:68
> devinet_ioctl+0x5bf/0xd30 net/ipv4/devinet.c:1199
> inet_ioctl+0x27c/0x2b0 net/ipv4/af_inet.c:1009
> sock_do_ioctl+0x84/0x1a0 net/socket.c:1254
> sock_ioctl+0x149/0x480 net/socket.c:1375
> 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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From 2c7239b8c86df91fad816365f5ae79806726780f Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum@suse.com>
Date: Mon, 12 Jan 2026 16:01:39 +0100
Subject: [PATCH] net: can: etas_es58x: full cleanup in the error case

Memory allocation can fail in the middle. Hence the cleanup
needs to be called in every case.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/net/can/usb/etas_es58x/es58x_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/etas_es58x/es58x_core.c b/drivers/net/can/usb/etas_es58x/es58x_core.c
index f799233c2b72..8a8764374713 100644
--- a/drivers/net/can/usb/etas_es58x/es58x_core.c
+++ b/drivers/net/can/usb/etas_es58x/es58x_core.c
@@ -1783,8 +1783,9 @@ static int es58x_open(struct net_device *netdev)

if (!es58x_dev->opened_channel_cnt) {
ret = es58x_alloc_rx_urbs(es58x_dev);
+ /* can fail partially */
if (ret)
- return ret;
+ goto free_urbs;

ret = es58x_set_realtime_diff_ns(es58x_dev);
if (ret)
--
2.52.0