Commit 57ea1d3d authored by Martin K. Petersen's avatar Martin K. Petersen Committed by Ben Hutchings

scsi: sd: Fix capacity calculation with 32-bit sector_t

commit 7c856152 upstream.

We previously made sure that the reported disk capacity was less than
0xffffffff blocks when the kernel was not compiled with large sector_t
support (CONFIG_LBDAF). However, this check assumed that the capacity
was reported in units of 512 bytes.

Add a sanity check function to ensure that we only enable disks if the
entire reported capacity can be expressed in terms of sector_t.
Reported-by: default avatarSteve Magnani <steve.magnani@digidescorp.com>
Cc: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: default avatarBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
[bwh: Backported to 3.2: use integer literal instead of U32_MAX]
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
parent 584063be
...@@ -1648,6 +1648,22 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp, ...@@ -1648,6 +1648,22 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
#define READ_CAPACITY_RETRIES_ON_RESET 10 #define READ_CAPACITY_RETRIES_ON_RESET 10
/*
* Ensure that we don't overflow sector_t when CONFIG_LBDAF is not set
* and the reported logical block size is bigger than 512 bytes. Note
* that last_sector is a u64 and therefore logical_to_sectors() is not
* applicable.
*/
static bool sd_addressable_capacity(u64 lba, unsigned int sector_size)
{
u64 last_sector = (lba + 1ULL) << (ilog2(sector_size) - 9);
if (sizeof(sector_t) == 4 && last_sector > 0xffffffffULL)
return false;
return true;
}
static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp, static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
unsigned char *buffer) unsigned char *buffer)
{ {
...@@ -1710,7 +1726,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp, ...@@ -1710,7 +1726,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
sd_read_protection_type(sdkp, buffer); sd_read_protection_type(sdkp, buffer);
if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) { if (!sd_addressable_capacity(lba, sector_size)) {
sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a " sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
"kernel compiled with support for large block " "kernel compiled with support for large block "
"devices.\n"); "devices.\n");
...@@ -1796,7 +1812,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp, ...@@ -1796,7 +1812,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
return sector_size; return sector_size;
} }
if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) { if (!sd_addressable_capacity(lba, sector_size)) {
sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a " sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
"kernel compiled with support for large block " "kernel compiled with support for large block "
"devices.\n"); "devices.\n");
......
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