UBSAN: shift-out-of-bounds in std_validate

From: syzbot
Date: Tue Jan 19 2021 - 13:48:16 EST


syzbot found the following issue on:

HEAD commit: 1e2a199f Merge tag 'spi-fix-v5.11-rc4' of git://git.kernel..
git tree: upstream
console output:
kernel config:
dashboard link:
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro:
C reproducer:

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+42d8c7c3d3e594b34346@xxxxxxxxxxxxxxxxxxxxxxxxx

UBSAN: shift-out-of-bounds in drivers/media/v4l2-core/v4l2-ctrls.c:2168:36
shift exponent 100 is too large for 64-bit type 'long long unsigned int'
CPU: 0 PID: 8469 Comm: syz-executor534 Not tainted 5.11.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x107/0x163 lib/dump_stack.c:120
ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
__ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395
std_validate.cold+0x19/0x1e drivers/media/v4l2-core/v4l2-ctrls.c:2168
validate_new drivers/media/v4l2-core/v4l2-ctrls.c:2477 [inline]
set_ctrl+0x207/0x4a0 drivers/media/v4l2-core/v4l2-ctrls.c:4425
set_ctrl_lock drivers/media/v4l2-core/v4l2-ctrls.c:4448 [inline]
v4l2_s_ctrl+0x2fd/0x4f0 drivers/media/v4l2-core/v4l2-ctrls.c:4469
v4l_s_ctrl+0x324/0x390 drivers/media/v4l2-core/v4l2-ioctl.c:2253
__video_do_ioctl+0xb94/0xe20 drivers/media/v4l2-core/v4l2-ioctl.c:2993
video_usercopy+0x23d/0x12d0 drivers/media/v4l2-core/v4l2-ioctl.c:3345
v4l2_ioctl+0x1b3/0x250 drivers/media/v4l2-core/v4l2-dev.c:360
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
RIP: 0033:0x443ee9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb d7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe02e7df08 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443ee9
RDX: 0000000020000140 RSI: 00000000c008561c RDI: 0000000000000003
RBP: 00000000006ce018 R08: 0000000000000000 R09: 00000000004002e0
R10: 000000000000000f R11: 0000000000000246 R12: 0000000000401b70
R13: 0000000000401c00 R14: 0000000000000000 R15: 0000000000000000

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