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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak in iterate_iovec include/linux/iov_iter.h:51 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x7c7/0x24b0 lib/iov_iter.c:185
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_iovec include/linux/iov_iter.h:51 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x7c7/0x24b0 lib/iov_iter.c:185
 copy_to_iter include/linux/uio.h:196 [inline]
 memcpy_to_msg include/linux/skbuff.h:4113 [inline]
 raw_recvmsg+0x2b8/0x9e0 net/can/raw.c:1008
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg+0x2c4/0x340 net/socket.c:1068
 ____sys_recvmsg+0x18a/0x620 net/socket.c:2803
 ___sys_recvmsg+0x223/0x840 net/socket.c:2845
 do_recvmmsg+0x627/0xfd0 net/socket.c:2931
 __sys_recvmmsg+0x10a/0x430 net/socket.c:3018
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xf5/0x180 net/compat.c:414
 ia32_sys_call+0x2797/0x40a0 arch/x86/include/generated/asm/syscalls_32.h:338
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1313 [inline]
 alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6515
 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
 sock_alloc_send_skb include/net/sock.h:1844 [inline]
 j1939_sk_alloc_skb net/can/j1939/socket.c:878 [inline]
 j1939_sk_send_loop net/can/j1939/socket.c:1142 [inline]
 j1939_sk_sendmsg+0xc0a/0x2730 net/can/j1939/socket.c:1277
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg+0x225/0x3c0 net/socket.c:2667
 __compat_sys_sendmsg net/compat.c:346 [inline]
 __do_compat_sys_sendmsg net/compat.c:353 [inline]
 __se_compat_sys_sendmsg net/compat.c:350 [inline]
 __ia32_compat_sys_sendmsg+0x9d/0xe0 net/compat.c:350
 ia32_sys_call+0x209f/0x40a0 arch/x86/include/generated/asm/syscalls_32.h:371
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Bytes 12-15 of 16 are uninitialized
Memory access of size 16 starts at ffff888117b4cf10
Data copied to user address 00000000200017c0

CPU: 1 PID: 5708 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller-00234-g7367539ad4b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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