devlink: refactor end checks in devlink_nl_cmd_region_read_dumpit

Clean up after recent fixes, move address calculations
around and change the variable init, so that we can have
just one start_offset == end_offset check.

Make the check a little stricter to preserve the -EINVAL
error if requested start offset is larger than the region
itself.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2020-05-13 10:28:22 -07:00 committed by David S. Miller
parent c7ad365761
commit 5a46b062e2
2 changed files with 31 additions and 25 deletions

View file

@ -4215,7 +4215,6 @@ static int devlink_nl_region_read_snapshot_fill(struct sk_buff *skb,
struct nlattr **attrs, struct nlattr **attrs,
u64 start_offset, u64 start_offset,
u64 end_offset, u64 end_offset,
bool dump,
u64 *new_offset) u64 *new_offset)
{ {
struct devlink_snapshot *snapshot; struct devlink_snapshot *snapshot;
@ -4230,9 +4229,6 @@ static int devlink_nl_region_read_snapshot_fill(struct sk_buff *skb,
if (!snapshot) if (!snapshot)
return -EINVAL; return -EINVAL;
if (end_offset > region->size || dump)
end_offset = region->size;
while (curr_offset < end_offset) { while (curr_offset < end_offset) {
u32 data_size; u32 data_size;
u8 *data; u8 *data;
@ -4260,13 +4256,12 @@ static int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb,
struct netlink_callback *cb) struct netlink_callback *cb)
{ {
const struct genl_dumpit_info *info = genl_dumpit_info(cb); const struct genl_dumpit_info *info = genl_dumpit_info(cb);
u64 ret_offset, start_offset, end_offset = 0; u64 ret_offset, start_offset, end_offset = U64_MAX;
struct nlattr **attrs = info->attrs; struct nlattr **attrs = info->attrs;
struct devlink_region *region; struct devlink_region *region;
struct nlattr *chunks_attr; struct nlattr *chunks_attr;
const char *region_name; const char *region_name;
struct devlink *devlink; struct devlink *devlink;
bool dump = true;
void *hdr; void *hdr;
int err; int err;
@ -4294,8 +4289,21 @@ static int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb,
goto out_unlock; goto out_unlock;
} }
if (attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR] &&
attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]) {
if (!start_offset)
start_offset =
nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]);
end_offset = nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]);
end_offset += nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]);
}
if (end_offset > region->size)
end_offset = region->size;
/* return 0 if there is no further data to read */ /* return 0 if there is no further data to read */
if (start_offset >= region->size) { if (start_offset == end_offset) {
err = 0; err = 0;
goto out_unlock; goto out_unlock;
} }
@ -4322,27 +4330,10 @@ static int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb,
goto nla_put_failure; goto nla_put_failure;
} }
if (attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR] &&
attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]) {
if (!start_offset)
start_offset =
nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]);
end_offset = nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]);
end_offset += nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]);
dump = false;
if (start_offset == end_offset) {
err = 0;
goto nla_put_failure;
}
}
err = devlink_nl_region_read_snapshot_fill(skb, devlink, err = devlink_nl_region_read_snapshot_fill(skb, devlink,
region, attrs, region, attrs,
start_offset, start_offset,
end_offset, dump, end_offset, &ret_offset);
&ret_offset);
if (err && err != -EMSGSIZE) if (err && err != -EMSGSIZE)
goto nla_put_failure; goto nla_put_failure;

View file

@ -146,6 +146,21 @@ regions_test()
check_region_snapshot_count dummy post-first-request 3 check_region_snapshot_count dummy post-first-request 3
devlink region dump $DL_HANDLE/dummy snapshot 25 >> /dev/null
check_err $? "Failed to dump snapshot with id 25"
devlink region read $DL_HANDLE/dummy snapshot 25 addr 0 len 1 >> /dev/null
check_err $? "Failed to read snapshot with id 25 (1 byte)"
devlink region read $DL_HANDLE/dummy snapshot 25 addr 128 len 128 >> /dev/null
check_err $? "Failed to read snapshot with id 25 (128 bytes)"
devlink region read $DL_HANDLE/dummy snapshot 25 addr 128 len $((1<<32)) >> /dev/null
check_err $? "Failed to read snapshot with id 25 (oversized)"
devlink region read $DL_HANDLE/dummy snapshot 25 addr $((1<<32)) len 128 >> /dev/null 2>&1
check_fail $? "Bad read of snapshot with id 25 did not fail"
devlink region del $DL_HANDLE/dummy snapshot 25 devlink region del $DL_HANDLE/dummy snapshot 25
check_err $? "Failed to delete snapshot with id 25" check_err $? "Failed to delete snapshot with id 25"