190a8843de
Add structure for parsed BPB information, struct fat_bios_param_block, and move all of the deserialization and validation logic from fat_fill_super() into fat_read_bpb(). Add a 'dos1xfloppy' mount option to infer DOS 2.x BIOS Parameter Block defaults from block device geometry for ancient floppies and floppy images, as a fall-back from the default BPB parsing logic. When fat_read_bpb() finds an invalid FAT filesystem and dos1xfloppy is set, fall back to fat_read_static_bpb(). fat_read_static_bpb() validates that the entire BPB is zero, and that the floppy has a DOS-style 8086 code bootstrapping header. Then it fills in default BPB values from media size and a table.[0] Media size is assumed to be static for archaic FAT volumes. See also: [1]. Fixes kernel.org bug #42617. [0]: https://en.wikipedia.org/wiki/File_Allocation_Table#Exceptions [1]: http://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html [hirofumi@mail.parknet.co.jp: fix missed error code] Signed-off-by: Conrad Meyer <cse.cem@gmail.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Tested-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| cache.c | ||
| dir.c | ||
| fat.h | ||
| fatent.c | ||
| file.c | ||
| inode.c | ||
| Kconfig | ||
| Makefile | ||
| misc.c | ||
| namei_msdos.c | ||
| namei_vfat.c | ||
| nfs.c | ||