dfc0: 00000000 00000000 00131420 00000119 00000000 00006364 003d0f00 76b650bc dfe0: 76b64ec0 76b64eb0 00018b10 00133470 socket: no more sockets ------------[ cut here ]------------ WARNING: CPU: 1 PID: 7719 at lib/refcount.c:28 refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28 refcount_t: underflow; use-after-free. Modules linked in: Kernel panic - not syncing: kernel: panic_on_warn set ... CPU: 1 UID: 0 PID: 7719 Comm: syz.1.1192 Not tainted 6.12.0-rc6-syzkaller #0 Hardware name: ARM-Versatile Express Call trace: [<8199c7b8>] (dump_backtrace) from [<8199c8b4>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257) r7:00000000 r6:82622f44 r5:00000000 r4:8203db14 [<8199c89c>] (show_stack) from [<819bad50>] (__dump_stack lib/dump_stack.c:94 [inline]) [<8199c89c>] (show_stack) from [<819bad50>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:120) [<819bacfc>] (dump_stack_lvl) from [<819bad90>] (dump_stack+0x18/0x1c lib/dump_stack.c:129) r5:00000000 r4:82870d18 [<819bad78>] (dump_stack) from [<8199d3e0>] (panic+0x120/0x374 kernel/panic.c:354) [<8199d2c0>] (panic) from [<80242118>] (check_panic_on_warn kernel/panic.c:243 [inline]) [<8199d2c0>] (panic) from [<80242118>] (get_taint+0x0/0x1c kernel/panic.c:238) r3:8260c5c4 r2:00000001 r1:82025ee8 r0:8202d950 r7:80840670 [<802420a4>] (check_panic_on_warn) from [<8024227c>] (__warn+0x80/0x188 kernel/panic.c:748) [<802421fc>] (__warn) from [<8024256c>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:783) r8:00000009 r7:8208c310 r6:dfcadc84 r5:84bb8c00 r4:00000000 [<80242388>] (warn_slowpath_fmt) from [<80840670>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28) r10:00000000 r9:850ba284 r8:00000000 r7:00000000 r6:81829e84 r5:00000002 r4:84b2a780 [<80840534>] (refcount_warn_saturate) from [<8149b940>] (__refcount_sub_and_test include/linux/refcount.h:275 [inline]) [<80840534>] (refcount_warn_saturate) from [<8149b940>] (__refcount_dec_and_test include/linux/refcount.h:307 [inline]) [<80840534>] (refcount_warn_saturate) from [<8149b940>] (refcount_dec_and_test include/linux/refcount.h:325 [inline]) [<80840534>] (refcount_warn_saturate) from [<8149b940>] (skb_unref include/linux/skbuff.h:1232 [inline]) [<80840534>] (refcount_warn_saturate) from [<8149b940>] (__sk_skb_reason_drop net/core/skbuff.c:1213 [inline]) [<80840534>] (refcount_warn_saturate) from [<8149b940>] (sk_skb_reason_drop+0x1d8/0x248 net/core/skbuff.c:1241) [<8149b768>] (sk_skb_reason_drop) from [<81829e84>] (kfree_skb_reason include/linux/skbuff.h:1262 [inline]) [<8149b768>] (sk_skb_reason_drop) from [<81829e84>] (kfree_skb include/linux/skbuff.h:1271 [inline]) [<8149b768>] (sk_skb_reason_drop) from [<81829e84>] (j1939_session_destroy+0x78/0x200 net/can/j1939/transport.c:282) r9:850ba284 r8:00000000 r7:dfcadf38 r6:84778150 r5:84778100 r4:84b2a780 [<81829e0c>] (j1939_session_destroy) from [<8182b1a0>] (__j1939_session_release net/can/j1939/transport.c:294 [inline]) [<81829e0c>] (j1939_session_destroy) from [<8182b1a0>] (kref_put include/linux/kref.h:65 [inline]) [<81829e0c>] (j1939_session_destroy) from [<8182b1a0>] (j1939_session_put+0x54/0x58 net/can/j1939/transport.c:299) r6:84778100 r5:83208a00 r4:00000004 [<8182b14c>] (j1939_session_put) from [<818291d0>] (j1939_sk_send_loop net/can/j1939/socket.c:1202 [inline]) [<8182b14c>] (j1939_session_put) from [<818291d0>] (j1939_sk_sendmsg+0x41c/0x548 net/can/j1939/socket.c:1277) [<81828db4>] (j1939_sk_sendmsg) from [<814865d4>] (sock_sendmsg_nosec net/socket.c:729 [inline]) [<81828db4>] (j1939_sk_sendmsg) from [<814865d4>] (__sock_sendmsg+0x44/0x78 net/socket.c:744) r10:00000000 r9:dfcaddd4 r8:dfcaddd4 r7:83208a00 r6:83208a00 r5:dfcadf38 r4:00000000 [<81486590>] (__sock_sendmsg) from [<814875d4>] (____sys_sendmsg+0x2a4/0x2c4 net/socket.c:2607) r7:83208a00 r6:00000000 r5:00000000 r4:dfcadf38 [<81487330>] (____sys_sendmsg) from [<8148953c>] (___sys_sendmsg+0x9c/0xd0 net/socket.c:2661) r10:dfcade34 r9:20000180 r8:00000000 r7:00000000 r6:83208a00 r5:dfcadf38 r4:00000000 [<814894a0>] (___sys_sendmsg) from [<81489a54>] (__sys_sendmsg net/socket.c:2690 [inline]) [<814894a0>] (___sys_sendmsg) from [<81489a54>] (__do_sys_sendmsg net/socket.c:2699 [inline]) [<814894a0>] (___sys_sendmsg) from [<81489a54>] (sys_sendmsg+0x78/0xbc net/socket.c:2697) r10:00000128 r9:84bb8c00 r8:8020029c r7:00000000 r6:20000180 r5:83208a00 r4:00000000 [<814899dc>] (sys_sendmsg) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfcadfa8 to 0xdfcadff0) dfa0: 00000000 00000000 00000003 20000180 00000000 00000000 dfc0: 00000000 00000000 002862f0 00000128 00000000 00006364 003d0f00 76b650bc dfe0: 76b64ec0 76b64eb0 00018b10 00133470 r7:00000128 r6:002862f0 r5:00000000 r4:00000000 Rebooting in 86400 seconds..