It is possible that the dm_ima_measure_on_* functions run at the same time as a table is getting swapped, but before the md->ima.active_table is updated by dm_ima_measure_on_device_resume(). Instead of using the current device size, use the size of the active table that is being measured (assuming there is one), so the information is consistent. Also, don't allocate a separate string to hold the capactiy. Just print it directly to the measurement buffer.
Signed-off-by: Benjamin Marzinski <[email protected]> --- drivers/md/dm-ima.c | 79 +++++++++++---------------------------------- drivers/md/dm-ima.h | 1 + 2 files changed, 20 insertions(+), 60 deletions(-) diff --git a/drivers/md/dm-ima.c b/drivers/md/dm-ima.c index 45038bd65f7b..ca6a33a0275e 100644 --- a/drivers/md/dm-ima.c +++ b/drivers/md/dm-ima.c @@ -151,22 +151,10 @@ static void dm_ima_measure_data(const char *event_name, const void *buf, size_t memalloc_noio_restore(noio_flag); } -/* - * Internal function to allocate and copy current device capacity for IMA measurements. - */ -static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **capacity_str, - bool noio) +static sector_t dm_ima_capacity(struct mapped_device *md) { - sector_t capacity; - - capacity = get_capacity(md->disk); - - *capacity_str = dm_ima_alloc(DM_IMA_DEVICE_CAPACITY_BUF_LEN, noio); - if (!(*capacity_str)) - return -ENOMEM; - - return scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;", - capacity); + return (md->ima.active_table.device_metadata) ? + md->ima.active_table.capacity : get_capacity(md->disk); } /* @@ -309,6 +297,7 @@ void dm_ima_measure_on_table_load(struct dm_table *table, table->md->ima.inactive_table.hash = digest_buf; table->md->ima.inactive_table.hash_len = strlen(digest_buf); table->md->ima.inactive_table.num_targets = num_targets; + table->md->ima.inactive_table.capacity = dm_table_get_size(table); kfree(table->md->ima.inactive_table.device_metadata); @@ -335,13 +324,12 @@ void dm_ima_measure_on_table_load(struct dm_table *table, void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap, struct dm_ima_context *context) { - char *device_table_data = NULL, *capacity_str = NULL; + char *device_table_data = NULL; char active[] = "active_table_hash="; unsigned int active_len = strlen(active); unsigned int l = 0; bool noio = true; bool nodata = true; - int capacity_len; if (unlikely(!context)) return; @@ -375,10 +363,6 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap, if (!device_table_data) goto error; - capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio); - if (capacity_len < 0) - goto error; - memcpy(device_table_data + l, DM_IMA_VERSION_STR, strlen(DM_IMA_VERSION_STR)); l += strlen(DM_IMA_VERSION_STR); @@ -411,14 +395,12 @@ void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap, DM_IMA_VERSION_STR, context->dev_name, context->dev_uuid); } - - memcpy(device_table_data + l, capacity_str, capacity_len); - l += capacity_len; + l += scnprintf(device_table_data + l, DM_IMA_DEVICE_BUF_LEN - l, + "current_device_capacity=%llu;", dm_ima_capacity(md)); dm_ima_measure_data("dm_device_resume", device_table_data, l, noio); error: - kfree(capacity_str); kfree(device_table_data); smp_mb__before_atomic(); @@ -433,21 +415,18 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all, struct dm_ima_context *context, unsigned int idx) { - char *device_table_data, *capacity_str = NULL; + char *device_table_data; char active_table_str[] = "active_table_hash="; char inactive_table_str[] = "inactive_table_hash="; char device_active_str[] = "device_active_metadata="; char device_inactive_str[] = "device_inactive_metadata="; - char remove_all_str[] = "remove_all="; unsigned int active_table_len = strlen(active_table_str); unsigned int inactive_table_len = strlen(inactive_table_str); unsigned int device_active_len = strlen(device_active_str); unsigned int device_inactive_len = strlen(device_inactive_str); - unsigned int remove_all_len = strlen(remove_all_str); unsigned int l = 0; bool noio = true; bool nodata = true; - int capacity_len; wait_event(md->ima.ima_wq, ((unsigned int)(atomic_read(&md->ima.measure_idx)) == idx)); @@ -460,12 +439,6 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all, if (!device_table_data) goto exit; - capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio); - if (capacity_len < 0) { - kfree(device_table_data); - goto exit; - } - memcpy(device_table_data + l, DM_IMA_VERSION_STR, strlen(DM_IMA_VERSION_STR)); l += strlen(DM_IMA_VERSION_STR); @@ -531,18 +504,13 @@ void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all, context->dev_uuid); } - memcpy(device_table_data + l, remove_all_str, remove_all_len); - l += remove_all_len; - memcpy(device_table_data + l, remove_all ? "y;" : "n;", 2); - l += 2; - - memcpy(device_table_data + l, capacity_str, capacity_len); - l += capacity_len; + l += scnprintf(device_table_data + l, (DM_IMA_DEVICE_BUF_LEN * 2) - l, + "remove_all=%c;current_device_capacity=%llu;", + remove_all ? 'y' : 'n', dm_ima_capacity(md)); dm_ima_measure_data("dm_device_remove", device_table_data, l, noio); kfree(device_table_data); - kfree(capacity_str); exit: kfree(md->ima.active_table.device_metadata); kfree(md->ima.inactive_table.device_metadata); @@ -565,12 +533,11 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, struct dm_ima_context *context) { unsigned int l = 0; - char *device_table_data = NULL, *capacity_str = NULL; + char *device_table_data = NULL; char inactive_str[] = "inactive_table_hash="; unsigned int inactive_len = strlen(inactive_str); bool noio = true; bool nodata = true; - int capacity_len; if (unlikely(!context)) return; @@ -584,10 +551,6 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, if (!device_table_data) goto error; - capacity_len = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio); - if (capacity_len < 0) - goto error; - memcpy(device_table_data + l, DM_IMA_VERSION_STR, strlen(DM_IMA_VERSION_STR)); l += strlen(DM_IMA_VERSION_STR); @@ -619,8 +582,8 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, context->dev_uuid); } - memcpy(device_table_data + l, capacity_str, capacity_len); - l += capacity_len; + l += scnprintf(device_table_data + l, DM_IMA_DEVICE_BUF_LEN - l, + "current_device_capacity=%llu;", dm_ima_capacity(md)); dm_ima_measure_data("dm_table_clear", device_table_data, l, noio); @@ -629,7 +592,6 @@ void dm_ima_measure_on_table_clear(struct mapped_device *md, kfree(md->ima.inactive_table.device_metadata); memset(&md->ima.inactive_table, 0, sizeof(md->ima.inactive_table)); - kfree(capacity_str); kfree(device_table_data); smp_mb__before_atomic(); @@ -644,7 +606,7 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md, struct dm_ima_context *context) { char *old_device_data = NULL; - char *combined_device_data = NULL, *capacity_str = NULL; + char *combined_device_data = NULL; bool noio = true; int len; struct dm_ima_device_table_metadata *table; @@ -663,9 +625,6 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md, if (!combined_device_data) goto exit; - if (dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio) < 0) - goto exit; - if (md->ima.active_table.device_metadata) old_device_data = md->ima.active_table.device_metadata; else if (md->ima.inactive_table.device_metadata) @@ -673,14 +632,14 @@ void dm_ima_measure_on_device_rename(struct mapped_device *md, else old_device_data = "table_rename=no_data;"; len = scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2, - "%s%snew_name=%s,new_uuid=%s;%s", DM_IMA_VERSION_STR, old_device_data, - context->dev_name, context->dev_uuid, capacity_str); + "%s%snew_name=%s,new_uuid=%s;current_device_capacity=%llu;", + DM_IMA_VERSION_STR, old_device_data, context->dev_name, + context->dev_uuid, dm_ima_capacity(md)); dm_ima_measure_data("dm_device_rename", combined_device_data, len, noio); -exit: - kfree(capacity_str); kfree(combined_device_data); +exit: if (md->ima.active_table.device_metadata) { table = &md->ima.active_table; dm_ima_copy_device_data(md, table->device_metadata, context, diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h index 2f2ac69042f2..d8b2438f1571 100644 --- a/drivers/md/dm-ima.h +++ b/drivers/md/dm-ima.h @@ -41,6 +41,7 @@ struct dm_ima_device_table_metadata { char *device_metadata; unsigned int device_metadata_len; unsigned int num_targets; + sector_t capacity; /* * Contains the sha256 hashes of the IMA measurements of the target -- 2.53.0
