ide-floppy: Fix unformatted media crash

A ZIP or similar with unformatted media will cause crashes when attempts
are made to read/write it in some cases. This is because bs_factor is
zero and we divide by it causing an oops.

As the size of a non-accessible/non-existant media is really a bit of a
zen question it doesn't matter if non-existant media is 512 bytes per
sector or zero. Setting it to 1 causes us to generate 512 bytes/sector
accesses and error properly.

Based on a fix found lurking in an ancient bugzilla entry since about 2004 (ugghhh)

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 1f8db9ac05d12def5a5fe8f49a7492e628e4a0bb..0c2625958b75960506ce8875c3761408285adcb6 100644 (file)
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -1438,7 +1438,8 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
        
        drive->bios_cyl = 0;
        drive->bios_head = drive->bios_sect = 0;
-       floppy->blocks = floppy->bs_factor = 0;
+       floppy->blocks = 0;
+       floppy->bs_factor = 1;
        set_capacity(floppy->disk, 0);
 
        idefloppy_create_read_capacity_cmd(&pc);