Re: [syzbot] [wireless?] memory leak in ieee80211_mesh_csa_beacon

From: syzbot

Date: Sat Sep 12 2026 - 16:12:46 EST


syzbot has found a reproducer for the following issue on:

HEAD commit: 5225b8eec4c9 mailmap: update entry for Jens Axboe
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1172e9f9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=736c81750115a056
dashboard link: https://syzkaller.appspot.com/bug?extid=f5752cd6b94fe38be666
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=12a9b615580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15d870c9580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/12d5d066d792/disk-5225b8ee.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f9bb3f95e482/vmlinux-5225b8ee.xz
kernel image: https://storage.googleapis.com/syzbot-assets/84ee8de2ba4a/bzImage-5225b8ee.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f5752cd6b94fe38be666@xxxxxxxxxxxxxxxxxxxxxxxxx

2026/09/12 20:09:52 executed programs: 5
BUG: memory leak
unreferenced object 0xffff888107ffb800 (size 1024):
comm "syz.0.18", pid 5913, jiffies 4294943824
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
d8 23 48 14 81 88 ff ff 00 00 00 00 00 00 00 00 .#H.............
backtrace (crc f81fd0):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4696 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
__kmalloc_cache_noprof+0x38f/0x420 mm/slub.c:5559
_kmalloc_noprof include/linux/slab.h:991 [inline]
ieee80211_mesh_csa_beacon+0x2e/0x100 net/mac80211/mesh.c:1547
ieee80211_set_csa_beacon net/mac80211/cfg.c:4674 [inline]
__ieee80211_channel_switch+0xb22/0xed0 net/mac80211/cfg.c:4795
rdev_channel_switch net/wireless/rdev-ops.h:1168 [inline]
nl80211_channel_switch+0x39b/0x780 net/wireless/nl80211.c:12388
genl_family_rcv_msg_doit+0x12e/0x1a0 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x302/0x440 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x89/0x1c0 net/netlink/af_netlink.c:2556
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x38f/0x4e0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x335/0x690 net/netlink/af_netlink.c:1900
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
____sys_sendmsg+0x54a/0x580 net/socket.c:2713
___sys_sendmsg+0x101/0x140 net/socket.c:2767
__sys_sendmsg+0xcd/0x140 net/socket.c:2799
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0xe9/0x530 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff888107ff8400 (size 1024):
comm "syz.0.19", pid 5915, jiffies 4294943825
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
d8 23 48 14 81 88 ff ff 00 00 00 00 00 00 00 00 .#H.............
backtrace (crc f81fd0):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4696 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
__kmalloc_cache_noprof+0x38f/0x420 mm/slub.c:5559
_kmalloc_noprof include/linux/slab.h:991 [inline]
ieee80211_mesh_csa_beacon+0x2e/0x100 net/mac80211/mesh.c:1547
ieee80211_set_csa_beacon net/mac80211/cfg.c:4674 [inline]
__ieee80211_channel_switch+0xb22/0xed0 net/mac80211/cfg.c:4795
rdev_channel_switch net/wireless/rdev-ops.h:1168 [inline]
nl80211_channel_switch+0x39b/0x780 net/wireless/nl80211.c:12388
genl_family_rcv_msg_doit+0x12e/0x1a0 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x302/0x440 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x89/0x1c0 net/netlink/af_netlink.c:2556
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x38f/0x4e0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x335/0x690 net/netlink/af_netlink.c:1900
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
____sys_sendmsg+0x54a/0x580 net/socket.c:2713
___sys_sendmsg+0x101/0x140 net/socket.c:2767
__sys_sendmsg+0xcd/0x140 net/socket.c:2799
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0xe9/0x530 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF


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