Hello,
syzbot found the following crash on:
HEAD commit: 245a4300 Merge branch 'rcu/kcsan' into tip/locking/kcsan
git tree:
https://github.com/google/ktsan.git kcsan
console output:
https://syzkaller.appspot.com/x/log.txt?x=11789f66e00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=a4b9db179318d21f
dashboard link:
https://syzkaller.appspot.com/bug?extid=aa6de90d54fa7c0888ad
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [
linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk el...@google.com]
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+aa6de9...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru
write to 0xffff88812c12a1c0 of 8 bytes by task 25221 on cpu 1:
bh_lru_install fs/buffer.c:1279 [inline]
__find_get_block fs/buffer.c:1338 [inline]
__find_get_block+0x62b/0x760 fs/buffer.c:1330
sb_find_get_block include/linux/buffer_head.h:338 [inline]
recently_deleted fs/ext4/ialloc.c:677 [inline]
find_inode_bit.isra.0+0x161/0x300 fs/ext4/ialloc.c:717
__ext4_new_inode+0xd45/0x2f10 fs/ext4/ialloc.c:909
ext4_symlink+0x31c/0x9b0 fs/ext4/namei.c:3275
vfs_symlink fs/namei.c:4131 [inline]
vfs_symlink+0x218/0x310 fs/namei.c:4117
do_symlinkat+0x1a5/0x1e0 fs/namei.c:4158
__do_sys_symlink fs/namei.c:4177 [inline]
__se_sys_symlink fs/namei.c:4175 [inline]
__x64_sys_symlink+0x3f/0x50 fs/namei.c:4175
do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffff88812c12a1c0 of 8 bytes by task 25262 on cpu 0:
has_bh_in_lru+0x44/0x90 fs/buffer.c:1427
on_each_cpu_cond_mask+0xa3/0x150 kernel/smp.c:695
on_each_cpu_cond+0x44/0x60 kernel/smp.c:721
invalidate_bh_lrus+0x32/0x40 fs/buffer.c:1436
invalidate_bdev+0x69/0x90 fs/block_dev.c:96
__loop_clr_fd+0x250/0x740 drivers/block/loop.c:1140
loop_clr_fd drivers/block/loop.c:1237 [inline]
lo_ioctl+0x24c/0xc80 drivers/block/loop.c:1606
__blkdev_driver_ioctl block/ioctl.c:277 [inline]
blkdev_ioctl+0xbe5/0x1260 block/ioctl.c:582
block_ioctl+0x95/0xc0 fs/block_dev.c:1983
vfs_ioctl fs/ioctl.c:47 [inline]
file_ioctl fs/ioctl.c:545 [inline]
do_vfs_ioctl+0x84f/0xcf0 fs/ioctl.c:732
ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
__do_sys_ioctl fs/ioctl.c:756 [inline]
__se_sys_ioctl fs/ioctl.c:754 [inline]
__x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25262 Comm: syz-executor.5 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
---
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