Message ID | 20240411103013.5547-1-mish.uxin2012@yandex.ru |
---|---|
State | New |
Headers | show |
Series | [v2,5.10/5.15] ata: libata-scsi: check cdb length for VARIABLE_LENGTH_CMD commands | expand |
On 4/11/24 19:30, Mikhail Ukhin wrote: > No upstream commit exists for this patch. > > Fuzzing of 5.10 stable branch reports a slab-out-of-bounds error in > ata_scsi_pass_thru. > > The error is fixed in 5.18 by commit ce70fd9a551a ("scsi: core: Remove the > cmd field from struct scsi_request") upstream. > Backporting this commit would require significant changes to the code so > it is bettter to use a simple fix for that particular error. > > The problem is that the length of the received SCSI command is not > validated if scsi_op == VARIABLE_LENGTH_CMD. It can lead to out-of-bounds > reading if the user sends a request with SCSI command of length less than > 32. > > Found by Linux Verification Center (linuxtesting.org) with Syzkaller. > > Signed-off-by: Artem Sadovnikov <ancowi69@gmail.com> > Signed-off-by: Mikhail Ivanov <iwanov-23@bk.ru> > Signed-off-by: Mikhail Ukhin <mish.uxin2012@yandex.ru> > --- > v2: The new addresses were added and the text was updated. > drivers/ata/libata-scsi.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c > index dfa090ccd21c..77589e911d3d 100644 > --- a/drivers/ata/libata-scsi.c > +++ b/drivers/ata/libata-scsi.c > @@ -4065,6 +4065,9 @@ int __ata_scsi_queuecmd(struct scsi_cmnd *scmd, struct ata_device *dev) > > if (unlikely(!scmd->cmd_len)) > goto bad_cdb_len; > + > + if (scsi_op == VARIABLE_LENGTH_CMD && scmd->cmd_len < 32) > + goto bad_cdb_len; This check should really be in ata_scsi_var_len_cdb_xlat(). Please move it to that function. > > if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) { > if (unlikely(scmd->cmd_len > dev->cdb_len))
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index dfa090ccd21c..77589e911d3d 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -4065,6 +4065,9 @@ int __ata_scsi_queuecmd(struct scsi_cmnd *scmd, struct ata_device *dev) if (unlikely(!scmd->cmd_len)) goto bad_cdb_len; + + if (scsi_op == VARIABLE_LENGTH_CMD && scmd->cmd_len < 32) + goto bad_cdb_len; if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) { if (unlikely(scmd->cmd_len > dev->cdb_len))