NTFS: Some utilities modify the boot sector but do not update the checksum.

Thus, relax the checking in fs/ntfs/super.c::is_boot_sector_ntfs() to
      only emit a warning when the checksum is incorrect rather than
      refusing the mount.  Thanks to Bernd Casimir for pointing this
      problem out.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
This commit is contained in:
Anton Altaparmakov 2005-04-04 16:20:14 +01:00
parent 251c8427c9
commit b0d2374d62
2 changed files with 13 additions and 4 deletions

View file

@ -105,6 +105,11 @@ ToDo/Notes:
non-resident by a concurrent file write.
- Remove checks for NULL before calling kfree() since kfree() does the
checking itself. (Jesper Juhl)
- Some utilities modify the boot sector but do not update the checksum.
Thus, relax the checking in fs/ntfs/super.c::is_boot_sector_ntfs() to
only emit a warning when the checksum is incorrect rather than
refusing the mount. Thanks to Bernd Casimir for pointing this
problem out.
2.1.22 - Many bug and race fixes and error handling improvements.

View file

@ -38,6 +38,7 @@
#include "debug.h"
#include "index.h"
#include "aops.h"
#include "layout.h"
#include "malloc.h"
#include "ntfs.h"
@ -532,16 +533,19 @@ static BOOL is_boot_sector_ntfs(const struct super_block *sb,
{
/*
* Check that checksum == sum of u32 values from b to the checksum
* field. If checksum is zero, no checking is done.
* field. If checksum is zero, no checking is done. We will work when
* the checksum test fails, since some utilities update the boot sector
* ignoring the checksum which leaves the checksum out-of-date. We
* report a warning if this is the case.
*/
if ((void*)b < (void*)&b->checksum && b->checksum) {
if ((void*)b < (void*)&b->checksum && b->checksum && !silent) {
le32 *u;
u32 i;
for (i = 0, u = (le32*)b; u < (le32*)(&b->checksum); ++u)
i += le32_to_cpup(u);
if (le32_to_cpu(b->checksum) != i)
goto not_ntfs;
ntfs_warning(sb, "Invalid boot sector checksum.");
}
/* Check OEMidentifier is "NTFS " */
if (b->oem_id != magicNTFS)
@ -591,7 +595,7 @@ static BOOL is_boot_sector_ntfs(const struct super_block *sb,
* many BIOSes will refuse to boot from a bootsector if the magic is
* incorrect, so we emit a warning.
*/
if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
if (!silent && b->end_of_sector_marker != const_cpu_to_le16(0xaa55))
ntfs_warning(sb, "Invalid end of sector marker.");
return TRUE;
not_ntfs: