Hello! This is an experimental automated report about issues detected by Coverity from a scan of next-20191108 as part of the linux-next weekly scan project: https://scan.coverity.com/projects/linux-next-weekly-scan You're getting this email because you were associated with the identified lines of code (noted below) that were touched by recent commits: 378f32bab371 ("ext4: introduce direct I/O write using iomap infrastructure") Coverity reported the following: *** CID 1487841: Integer handling issues (OVERFLOW_BEFORE_WIDEN) /fs/ext4/inode.c: 3388 in ext4_iomap_alloc() 3382 /* 3383 * We use i_size instead of i_disksize here because delalloc writeback 3384 * can complete at any point during the I/O and subsequently push the 3385 * i_disksize out to i_size. This could be beyond where direct I/O is 3386 * happening and thus expose allocated blocks to direct I/O reads. 3387 */ vvv CID 1487841: Integer handling issues (OVERFLOW_BEFORE_WIDEN) vvv Potentially overflowing expression "1 << blkbits" with type "int" (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in a context that expects an expression of type "loff_t" (64 bits, signed). 3388 else if ((map->m_lblk * (1 << blkbits)) >= i_size_read(inode)) 3389 m_flags = EXT4_GET_BLOCKS_CREATE; 3390 else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) 3391 m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT; 3392 3393 ret = ext4_map_blocks(handle, inode, map, m_flags); If this is a false positive, please let us know so we can mark it as such, or teach the Coverity rules to be smarter. If not, please make sure fixes get into linux-next. :) For patches fixing this, please include these lines (but double-check the "Fixes" first): Reported-by: coverity-bot <keescook+coverity-bot@xxxxxxxxxxxx> Addresses-Coverity-ID: 1487841 ("Integer handling issues") Fixes: 378f32bab371 ("ext4: introduce direct I/O write using iomap infrastructure") Thanks for your attention! -- Coverity-bot
