From: Hannes Reinecke hare@suse.de
mainline inclusion from mainline-v5.14-rc1 commit 8793613de913e03e7c884f4cc56e350bc716431e category: bugfix bugzilla: 189811, https://gitee.com/src-openeuler/kernel/issues/I9FNFK CVE: CVE-2021-47182
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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The description for scsi_mode_sense() claims to return the number of valid bytes on success, which is not what the code does. Additionally there is no gain in returning the SCSI status, as everything the callers do is to check against scsi_result_is_good(), which is what scsi_mode_sense() does already. So change the calling convention to return a standard error code on failure, and 0 on success, and adapt the description and all callers.
Link: https://lore.kernel.org/r/20210427083046.31620-4-hare@suse.de Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Hannes Reinecke hare@suse.de Signed-off-by: Martin K. Petersen martin.petersen@oracle.com
Conflict: drivers/scsi/sd.c
Signed-off-by: Li Nan linan122@huawei.com --- drivers/scsi/scsi_lib.c | 10 ++++++---- drivers/scsi/scsi_transport_sas.c | 9 ++++----- drivers/scsi/sd.c | 12 ++++++------ drivers/scsi/sr.c | 2 +- 4 files changed, 17 insertions(+), 16 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 719cdf5628ec..ad12c48bd835 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2655,9 +2655,7 @@ EXPORT_SYMBOL_GPL(scsi_mode_select); * @sshdr: place to put sense data (or NULL if no sense to be collected). * must be SCSI_SENSE_BUFFERSIZE big. * - * Returns zero if unsuccessful, or the header offset (either 4 - * or 8 depending on whether a six or ten byte command was - * issued) if successful. + * Returns zero if successful, or a negative error number on failure */ int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, @@ -2702,6 +2700,8 @@ scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, sshdr, timeout, retries, NULL); + if (result < 0) + return result;
/* This code looks awful: what it's doing is making sure an * ILLEGAL REQUEST sense return identifies the actual command @@ -2746,13 +2746,15 @@ scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, data->block_descriptor_length = buffer[3]; } data->header_length = header_length; + result = 0; } else if ((status_byte(result) == CHECK_CONDITION) && scsi_sense_valid(sshdr) && sshdr->sense_key == UNIT_ATTENTION && retry_count) { retry_count--; goto retry; } - + if (result > 0) + result = -EIO; return result; } EXPORT_SYMBOL(scsi_mode_sense); diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index 0cd16e80b019..824e4f053e68 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -1235,16 +1235,15 @@ int sas_read_port_mode_page(struct scsi_device *sdev) char *buffer = kzalloc(BUF_SIZE, GFP_KERNEL), *msdata; struct sas_end_device *rdev = sas_sdev_to_rdev(sdev); struct scsi_mode_data mode_data; - int res, error; + int error;
if (!buffer) return -ENOMEM;
- res = scsi_mode_sense(sdev, 1, 0x19, buffer, BUF_SIZE, 30*HZ, 3, - &mode_data, NULL); + error = scsi_mode_sense(sdev, 1, 0x19, buffer, BUF_SIZE, 30*HZ, 3, + &mode_data, NULL);
- error = -EINVAL; - if (!scsi_status_is_good(res)) + if (error) goto out;
msdata = buffer + mode_data.header_length + diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index e674565ae488..45d6174d3458 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2651,18 +2651,18 @@ sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer) * 5: Illegal Request, Sense Code 24: Invalid field in * CDB. */ - if (!scsi_status_is_good(res)) + if (res < 0) res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
/* * Third attempt: ask 255 bytes, as we did earlier. */ - if (!scsi_status_is_good(res)) + if (res < 0) res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255, &data, NULL); }
- if (!scsi_status_is_good(res)) { + if (res < 0) { sd_first_printk(KERN_WARNING, sdkp, "Test WP failed, assume Write Enabled\n"); } else { @@ -2723,7 +2723,7 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer) res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len, &data, &sshdr);
- if (!scsi_status_is_good(res)) + if (res < 0) goto bad_sense;
if (!data.header_length) { @@ -2755,7 +2755,7 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer) res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len, &data, &sshdr);
- if (scsi_status_is_good(res)) { + if (!res) { int offset = data.header_length + data.block_descriptor_length;
while (offset < len) { @@ -2873,7 +2873,7 @@ static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer) res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT, SD_MAX_RETRIES, &data, &sshdr);
- if (!scsi_status_is_good(res) || !data.header_length || + if (res < 0 || !data.header_length || data.length < 6) { sd_first_printk(KERN_WARNING, sdkp, "getting Control mode page failed, assume no ATO\n"); diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 180087d1c6cd..f464d5c050fc 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -898,7 +898,7 @@ static void get_capabilities(struct scsi_cd *cd) rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len, SR_TIMEOUT, 3, &data, NULL);
- if (!scsi_status_is_good(rc) || data.length > ms_len || + if (rc < 0 || data.length > ms_len || data.header_length + data.block_descriptor_length > data.length) { /* failed, drive doesn't have capabilities mode page */ cd->cdi.speed = 1;