[v6.6] panic: runtime error: floating point error

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 147338df3487 Linux 6.6.108
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15cb527c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=59ec4366161a98df4e4f
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17b8c2e2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/535c4ea595d6/disk-147338df.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2d6c4ceaffc3/vmlinux-147338df.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0ed56233e74e/bzImage-147338df.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+59ec43...@syzkaller.appspotmail.com

2025/09/26 10:12:05 executed programs: 2
panic: runtime error: floating point error
[signal SIGFPE: floating-point exception code=0x80 addr=0x0 pc=0x4082ad]

goroutine 9 [running]:
internal/runtime/maps.h2(...)
/usr/local/go/src/internal/runtime/maps/map.go:191
internal/runtime/maps.(*Map).deleteSmall(0xc003911170, 0x1484720, 0xc003c12004?, 0xc0039656a0)
/usr/local/go/src/internal/runtime/maps/map.go:682 +0x2d
internal/runtime/maps.(*Map).Delete(0xc003911170, 0x1484720, 0xc0039656a0)
/usr/local/go/src/internal/runtime/maps/map.go:658 +0xdf
github.com/google/syzkaller/pkg/rpcserver.(*Runner).handleExecResult(0xc0002b46c0, 0xc0039e53b0)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/runner.go:407 +0x9f
github.com/google/syzkaller/pkg/rpcserver.(*Runner).ConnectionLoop(0xc0002b46c0)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/runner.go:205 +0x3a9
github.com/google/syzkaller/pkg/rpcserver.(*server).connectionLoop(0xc00130c5a0, {0x22d0430?, 0xc002607090?}, 0xc0002b46c0)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/rpcserver.go:439 +0x196
github.com/google/syzkaller/pkg/rpcserver.(*server).handleRunnerConn(0xc00130c5a0, {0x22d0430, 0xc002607090}, 0xc0002b46c0, 0xc0026070e0)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/rpcserver.go:362 +0x54a
github.com/google/syzkaller/pkg/rpcserver.(*server).handleConn(0xc00130c5a0, {0x22d0430, 0xc002607090}, 0xc0026070e0)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/rpcserver.go:324 +0x2aa
github.com/google/syzkaller/pkg/rpcserver.(*server).Serve.func1.1({0x22d0430?, 0xc002607090?}, 0x0?)
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/rpcserver/rpcserver.go:244 +0x31
github.com/google/syzkaller/pkg/flatrpc.(*Serv).Serve.func2()
/syzkaller/gopath/src/github.com/google/syzkaller/pkg/flatrpc/conn.go:78 +0x198
golang.org/x/sync/errgroup.(*Group).Go.func1()
/syzkaller/gopath/pkg/mod/golang.org/x/sy...@v0.16.0/errgroup/errgroup.go:93 +0x50
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 29
/syzkaller/gopath/pkg/mod/golang.org/x/sy...@v0.16.0/errgroup/errgroup.go:78 +0x93


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