This patch fixes an out-of-bounds error in sd_read_cache_type(), found by Google's AddressSanitizer tool. When the loop ends, we know that "offset" lies beyond the end of the data in the buffer, so no Caching mode page was found. In theory it may be present, but the buffer size is limited to 512 bytes.
Signed-off-by: Alan Stern <[email protected]> Reported-by: Dmitry Vyukov <[email protected]> CC: <[email protected]> --- [as1709] drivers/scsi/sd.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) Index: usb-3.11/drivers/scsi/sd.c =================================================================== --- usb-3.11.orig/drivers/scsi/sd.c +++ usb-3.11/drivers/scsi/sd.c @@ -2419,14 +2419,9 @@ sd_read_cache_type(struct scsi_disk *sdk } } - if (modepage == 0x3F) { - sd_printk(KERN_ERR, sdkp, "No Caching mode page " - "present\n"); - goto defaults; - } else if ((buffer[offset] & 0x3f) != modepage) { - sd_printk(KERN_ERR, sdkp, "Got wrong page\n"); - goto defaults; - } + sd_printk(KERN_ERR, sdkp, "No Caching mode page found\n"); + goto defaults; + Page_found: if (modepage == 8) { sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0); -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
