udf: fix the problem that the disc content is not displayed
[ Upstream commit 5cdc4a69 ] When the capacity of the disc is too large (assuming the 4.7G specification), the disc (UDF file system) will be burned multiple times in the windows (Multisession Usage). When the remaining capacity of the CD is less than 300M (estimated value, for reference only), open the CD in the Linux system, the content of the CD is displayed as blank (the kernel will say "No VRS found"). Windows can display the contents of the CD normally. Through analysis, in the "fs/udf/super.c": udf_check_vsd function, the actual value of VSD_MAX_SECTOR_OFFSET may be much larger than 0x800000. According to the current code logic, it is found that the type of sbi->s_session is "__s32", when the remaining capacity of the disc is less than 300M (take a set of test values: sector=3154903040, sbi->s_session=1540464, sb->s_blocksize_bits=11 ), the calculation result of "sbi->s_session << sb->s_blocksize_bits" wi...
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