diff options
Diffstat (limited to 'libparted/fs/fat/fat.c')
-rw-r--r-- | libparted/fs/fat/fat.c | 58 |
1 files changed, 53 insertions, 5 deletions
diff --git a/libparted/fs/fat/fat.c b/libparted/fs/fat/fat.c index ada2d62..94b3981 100644 --- a/libparted/fs/fat/fat.c +++ b/libparted/fs/fat/fat.c @@ -109,6 +109,45 @@ fat_set_frag_sectors (PedFileSystem* fs, PedSector frag_sectors) return 1; } +/* FIXME: factor out this function: copied from dos.c + Read sector, SECTOR_NUM (which has length DEV->sector_size) into malloc'd + storage. If the read fails, free the memory and return zero without + modifying *BUF. Otherwise, set *BUF to the new buffer and return 1. */ +static int +read_sector (const PedDevice *dev, PedSector sector_num, char **buf) +{ + char *b = ped_malloc (dev->sector_size); + PED_ASSERT (b != NULL, return 0); + if (!ped_device_read (dev, b, sector_num, 1)) { + free (b); + return 0; + } + *buf = b; + return 1; +} + +/* Just like fat_boot_sector_read, but works with sector_size > 512. + Upon success, set *SECTOR_BUF to the malloc'd sector_size-byte buffer, + and copy the first bytes of that buffer into FBS. Upon success, + the caller must free *SECTOR_BUF. */ +static int +fat_boot_sector_read_2 (FatBootSector* fbs, char **sector_buf, + const PedGeometry *geom) +{ + char *buf; + *sector_buf = NULL; + if (!read_sector (geom->dev, 0, &buf)) + return 0; + if (!fat_boot_sector_is_sane (buf)) { + free (buf); + return 0; + } + *sector_buf = buf; + if (fbs) + memcpy (fbs, buf, sizeof *fbs); + return 1; +} + PedGeometry* fat_probe (PedGeometry* geom, FatType* fat_type) { @@ -121,7 +160,8 @@ fat_probe (PedGeometry* geom, FatType* fat_type) goto error; fs_info = (FatSpecific*) fs->type_specific; - if (!fat_boot_sector_read (&fs_info->boot_sector, geom)) + char *s0; + if (!fat_boot_sector_read_2 (&fs_info->boot_sector, &s0, geom)) goto error_free_fs; if (!fat_boot_sector_analyse (&fs_info->boot_sector, fs)) goto error_free_fs; @@ -131,10 +171,12 @@ fat_probe (PedGeometry* geom, FatType* fat_type) fs_info->sector_count); fat_free (fs); + free (s0); return result; error_free_fs: fat_free (fs); + free (s0); error: return NULL; } @@ -173,7 +215,9 @@ fat_clobber (PedGeometry* geom) { FatBootSector boot_sector; - if (!fat_boot_sector_read (&boot_sector, geom)) + // FIXME: remove this comment: ARGH: clobbers stack when sector_size > 512 + char *s0; + if (!fat_boot_sector_read_2 (&boot_sector, &s0, geom)) return 1; boot_sector.system_id[0] = 0; @@ -183,7 +227,9 @@ fat_clobber (PedGeometry* geom) if (boot_sector.u.fat32.fat_name[0] == 'F') boot_sector.u.fat32.fat_name[0] = 0; - return ped_geometry_write (geom, &boot_sector, 0, 1); + int write_ok = ped_geometry_write (geom, s0, 0, 1); + free (s0); + return write_ok; } static int @@ -220,7 +266,8 @@ fat_open (PedGeometry* geom) goto error; fs_info = (FatSpecific*) fs->type_specific; - if (!fat_boot_sector_read (&fs_info->boot_sector, geom)) + char *s0; + if (!fat_boot_sector_read_2 (&fs_info->boot_sector, &s0, geom)) goto error_free_fs; if (!fat_boot_sector_analyse (&fs_info->boot_sector, fs)) goto error_free_fs; @@ -239,6 +286,7 @@ fat_open (PedGeometry* geom) if (!fat_collect_cluster_info (fs)) goto error_free_buffers; + free (s0); return fs; error_free_buffers: @@ -246,6 +294,7 @@ error_free_buffers: error_free_fat_table: fat_table_destroy (fs_info->fat); error_free_fs: + free (s0); fat_free (fs); error: return NULL; @@ -887,4 +936,3 @@ ped_file_system_fat_done () ped_file_system_type_unregister (&fat16_type); ped_file_system_type_unregister (&fat32_type); } - |