[v6.1] kernel BUG in ipgre_header

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fb2635ac69ab Linux 6.1.62
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16fa073f680000
kernel config: https://syzkaller.appspot.com/x/.config?x=87ac2800e03db39a
dashboard link: https://syzkaller.appspot.com/bug?extid=b00d8e27a887add75dac
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dcc1cd63efb4/disk-fb2635ac.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7ba80cff2748/vmlinux-fb2635ac.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7224e10d13ba/Image-fb2635ac.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b00d8e...@syzkaller.appspotmail.com

skbuff: skb_under_panic: text:ffff800010d79ba8 len:-32748 put:-32748 head:ffff00012aa4b800 data:ffff00002aa538ac tail:0xc0 end:0xc0 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:120!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 12265 Comm: syz-executor.2 Not tainted 6.1.62-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic net/core/skbuff.c:116 [inline]
pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
lr : skb_panic net/core/skbuff.c:116 [inline]
lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
sp : ffff80001e6d74b0
x29: ffff80001e6d74c0 x28: 1ffff00003cdaf08 x27: dfff800000000000
x26: ffff0000cb33c3d0 x25: 00000000000000c0 x24: ffff00002aa538ac
x23: ffff00012aa4b800 x22: 00000000ffff8014 x21: 00000000000000c0
x20: 00000000ffff8014 x19: ffff800010d79ba8 x18: 1fffe000368b0776
x17: ffff80001580d000 x16: ffff80001213551c x15: ffff0001b4583bbc
x14: 1ffff00002b020b0 x13: dfff800000000000 x12: 0000000000040000
x11: 0000000000001248 x10: ffff8000241ca000 x9 : fcece6231866ab00
x8 : fcece6231866ab00 x7 : ffff80000827db78 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : ffff80000aa8604c
x2 : ffff0001b4583cd0 x1 : 0000000100000000 x0 : 000000000000008e
Call trace:
skb_panic net/core/skbuff.c:116 [inline]
skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
skb_push+0x104/0x11c net/core/skbuff.c:2180
ipgre_header+0x78/0x3c4 net/ipv4/ip_gre.c:852
dev_hard_header include/linux/netdevice.h:3073 [inline]
packet_snd net/packet/af_packet.c:3028 [inline]
packet_sendmsg+0x3068/0x4ce0 net/packet/af_packet.c:3108
sock_sendmsg_nosec net/socket.c:716 [inline]
__sock_sendmsg net/socket.c:728 [inline]
____sys_sendmsg+0x558/0x844 net/socket.c:2499
___sys_sendmsg net/socket.c:2553 [inline]
__sys_sendmsg+0x26c/0x33c net/socket.c:2582
__do_sys_sendmsg net/socket.c:2591 [inline]
__se_sys_sendmsg net/socket.c:2589 [inline]
__arm64_sys_sendmsg+0x80/0x94 net/socket.c:2589
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: aa1803e6 aa1903e7 a90023f5 94754276 (d4210000)
---[ end trace 0000000000000000 ]---


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: fb2635ac69ab Linux 6.1.62
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=14e59214e80000

kernel config: https://syzkaller.appspot.com/x/.config?x=87ac2800e03db39a
dashboard link: https://syzkaller.appspot.com/bug?extid=b00d8e27a887add75dac
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13ad289f680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=141d0ef4e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dcc1cd63efb4/disk-fb2635ac.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7ba80cff2748/vmlinux-fb2635ac.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7224e10d13ba/Image-fb2635ac.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b00d8e...@syzkaller.appspotmail.com

skbuff: skb_under_panic: text:ffff800010d79ba8 len:-32748 put:-32748 head:ffff0000d0fc6400 data:fffeffffd0fce4ac tail:0xc0 end:0xc0 dev:<NULL>

------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:120!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:

CPU: 0 PID: 4227 Comm: syz-executor330 Not tainted 6.1.62-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic net/core/skbuff.c:116 [inline]
pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130
lr : skb_panic net/core/skbuff.c:116 [inline]
lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:130

sp : ffff80001ddd74b0
x29: ffff80001ddd74c0 x28: 1ffff00003bbaf08 x27: dfff800000000000
x26: ffff0000d2526dd0 x25: 00000000000000c0 x24: fffeffffd0fce4ac
x23: ffff0000d0fc6400 x22: 00000000ffff8014 x21: 00000000000000c0
x20: 00000000ffff8014 x19: ffff800010d79ba8 x18: 1fffe000368ac776
x17: ffff80001580d000 x16: ffff80001213551c x15: ffff0001b4563bbc
x14: 1ffff00002b020b0 x13: dfff800000000000 x12: 0000000000000001
x11: ff80800008346830 x10: 0000000000000000 x9 : e7cdc4ce9e931400
x8 : e7cdc4ce9e931400 x7 : ffff80000827db78 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : ffff80000858a904
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000008e

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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