syzbot


Internal error in fat_generic_ioctl

Status: upstream: reported C repro on 2025/08/09 00:01
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+f761bba47ccbb8d8e72e@syzkaller.appspotmail.com
First crash: 16d, last: 1d13h
Bug presence (2)
Date Name Commit Repro Result
2025/08/13 linux-5.15.y (ToT) c79648372d02 C [report] Internal error in fat_generic_ioctl
2025/08/13 upstream (ToT) 8742b2d8935f C Didn't crash

Sample crash report:
loop0: detected capacity change from 0 to 256
Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4209 Comm: syz.0.17 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 42400405 (nZcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=jc)
pc : fat_generic_ioctl+0x694/0xeac fs/fat/file.c:163
lr : fat_ioctl_get_attributes fs/fat/file.c:29 [inline]
lr : fat_generic_ioctl+0x670/0xeac fs/fat/file.c:163
sp : ffff80001fcf7a80
x29: ffff80001fcf7ba0 x28: ffff0000d5c21b40 x27: 0000000000000010
x26: dfff800000000000 x25: ffff700003f9ef54 x24: 00000000000041c0
x23: 0000000000000010 x22: 0000000000000092 x21: 0000000000400140
x20: 0000000000000000 x19: 0000000000000001 x18: 0000000000000000
x17: ffff800016d04000 x16: ffff800008e4664c x15: ffff8000167e4500
x14: ffff0000d5c22540 x13: 1ffff0000282e06b x12: 0000000000000000
x11: 0000000000000010 x10: 0000ffffffffffff x9 : 0000000000000000
x8 : 00000000fffffff2 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
 fat_ioctl_get_attributes fs/fat/file.c:32 [inline]
 fat_generic_ioctl+0x694/0xeac fs/fat/file.c:163
 fat_dir_ioctl+0x184/0x36c fs/fat/dir.c:804
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: ea2a013f 9a9f028c d503229f b800098b (93407d00) 
---[ end trace 065221c166a169ba ]---
----------------
Code disassembly (best guess):
   0:	ea2a013f 	bics	xzr, x9, x10
   4:	9a9f028c 	csel	x12, x20, xzr, eq	// eq = none
   8:	d503229f 	csdb
   c:	b800098b 	sttr	w11, [x12]
* 10:	93407d00 	sxtw	x0, w8 <-- trapping instruction

Crashes (94):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/10 22:47 linux-5.15.y c79648372d02 32a0e5ed .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/23 23:23 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/23 19:51 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/22 22:37 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/22 16:42 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/22 15:23 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/22 02:22 linux-5.15.y c79648372d02 3e79b825 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/22 02:20 linux-5.15.y c79648372d02 3e79b825 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/20 09:14 linux-5.15.y c79648372d02 79512909 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/20 04:31 linux-5.15.y c79648372d02 79512909 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/20 01:27 linux-5.15.y c79648372d02 254a27c1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/18 02:42 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/17 16:36 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/17 14:04 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/17 12:08 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/17 04:05 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/17 04:03 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/16 20:04 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/16 18:58 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 20:38 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 17:25 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 11:36 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 09:44 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 03:25 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 03:24 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 03:23 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 03:11 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/15 03:11 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 05:33 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 05:31 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 04:14 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 04:13 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 03:09 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/14 03:07 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 23:00 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 22:59 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 11:30 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 11:30 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 05:10 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/13 05:09 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/11 20:58 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/11 20:58 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/10 06:41 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/10 06:40 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
2025/08/08 22:12 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 Internal error in fat_generic_ioctl
* Struck through repros no longer work on HEAD.