diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2012-09-07 17:30:40 +0200 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2012-09-17 17:13:38 -0700 |
| commit | a50da144d048f9dbebed2b1441ed779d6bbbcd03 (patch) | |
| tree | 25290267964578f79c10590a6511d10b85e7de96 /drivers/target | |
| parent | 7a3f369ce31694017996524a1cdb08208a839077 (diff) | |
target: support zero allocation length in SBC commands
READ CAPACITY must be subject to the same treatment as INQUIRY,
REQUEST SENSE, and MODE SENSE, but there are no pre-existing bugs
to fix here. Just use an on-stack buffer, and copy to it after
checking the return value of transport_kmap_data_sg.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target')
| -rw-r--r-- | drivers/target/target_core_sbc.c | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index a9dd9469e3b..868f8aa04f1 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -40,8 +40,9 @@ static int sbc_emulate_readcapacity(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; - unsigned char *buf; unsigned long long blocks_long = dev->transport->get_blocks(dev); + unsigned char *rbuf; + unsigned char buf[8]; u32 blocks; if (blocks_long >= 0x00000000ffffffff) @@ -49,8 +50,6 @@ static int sbc_emulate_readcapacity(struct se_cmd *cmd) else blocks = (u32)blocks_long; - buf = transport_kmap_data_sg(cmd); - buf[0] = (blocks >> 24) & 0xff; buf[1] = (blocks >> 16) & 0xff; buf[2] = (blocks >> 8) & 0xff; @@ -60,7 +59,11 @@ static int sbc_emulate_readcapacity(struct se_cmd *cmd) buf[6] = (dev->se_sub_dev->se_dev_attrib.block_size >> 8) & 0xff; buf[7] = dev->se_sub_dev->se_dev_attrib.block_size & 0xff; - transport_kunmap_data_sg(cmd); + rbuf = transport_kmap_data_sg(cmd); + if (rbuf) { + memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); + transport_kunmap_data_sg(cmd); + } target_complete_cmd(cmd, GOOD); return 0; @@ -69,11 +72,11 @@ static int sbc_emulate_readcapacity(struct se_cmd *cmd) static int sbc_emulate_readcapacity_16(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; - unsigned char *buf; + unsigned char *rbuf; + unsigned char buf[32]; unsigned long long blocks = dev->transport->get_blocks(dev); - buf = transport_kmap_data_sg(cmd); - + memset(buf, 0, sizeof(buf)); buf[0] = (blocks >> 56) & 0xff; buf[1] = (blocks >> 48) & 0xff; buf[2] = (blocks >> 40) & 0xff; @@ -93,7 +96,11 @@ static int sbc_emulate_readcapacity_16(struct se_cmd *cmd) if (dev->se_sub_dev->se_dev_attrib.emulate_tpu || dev->se_sub_dev->se_dev_attrib.emulate_tpws) buf[14] = 0x80; - transport_kunmap_data_sg(cmd); + rbuf = transport_kmap_data_sg(cmd); + if (rbuf) { + memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); + transport_kunmap_data_sg(cmd); + } target_complete_cmd(cmd, GOOD); return 0; |