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Tasks #64819
closedTasks #63293: Implement fscrypt in libcephfs and cephfs-fuse
Tasks #64160: RMW race detection
data corruption during rmw after lseek
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Description
There's data corruption during a rmw after a seek.
reproducer
import os
def write_fill(fd, fill, size, offset):
s = ''
for i in range(0,size):
s += fill
os.lseek(fd, offset - int(size / 2), 0)
os.write(fd, str.encode(s))
file = 'file.log'
fd = os.open(file, os.O_RDWR|os.O_CREAT)
s = write_fill(fd, 's', 32, 16)
s = write_fill(fd, 't', 8, 16)
os.close(fd)
Run the above on fscrypt enabled dir and non-fscrypt dir.
fscrypt enabled dir
hexdump /mnt/mycephfs/fscrypt_test_unlocked_ffsb/file.log 0000000 7373 7373 7373 7373 7373 7373 7474 7474 0000010 7474 7474 0000 0000 0000 0000 0000 0000 0000020
non-fscrypt dir
hexdump file.log 0000000 7373 7373 7373 7373 7373 7373 7474 7474 0000010 7474 7474 7373 7373 7373 7373 7373 7373 0000020
fscrypt case, file.log does not have trailing ssss... as it should
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