diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2024-02-28 09:55:42 +0100 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2024-03-04 14:33:51 +0100 |
| commit | 8ade3356b25ab2522892a21832a709e7ad5f8168 (patch) | |
| tree | 1e62fa0ea57e1bb3e46d600230c050b3ac2c24f2 /net/wireless/scan.c | |
| parent | 22667035e5ddb7b68c7d473693b321fb9e20a397 (diff) | |
| download | linux-8ade3356b25ab2522892a21832a709e7ad5f8168.tar.gz linux-8ade3356b25ab2522892a21832a709e7ad5f8168.tar.bz2 linux-8ade3356b25ab2522892a21832a709e7ad5f8168.zip | |
wifi: cfg80211: allow cfg80211_defragment_element() without output
If we just want to determine the length of the fragmented
data, we basically need the same logic, and really we want
it to be _literally_ the same logic, so it cannot be out
of sync in any way.
Allow calling cfg80211_defragment_element() without an output
buffer, where it then just returns the required output size.
Also add this to the tests, just to exercise it, using the
pre-calculated length to really do the defragmentation, which
checks that this is sufficient.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://msgid.link/20240228095718.6d6565b9e3f2.Ib441903f4b8644ba04b1c766f90580ee6f54fc66@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/wireless/scan.c')
| -rw-r--r-- | net/wireless/scan.c | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 9377a43aa5f7..5a5dd3ce497f 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -2504,16 +2504,22 @@ ssize_t cfg80211_defragment_element(const struct element *elem, const u8 *ies, if (elem->id == WLAN_EID_EXTENSION) { copied = elem->datalen - 1; - if (copied > data_len) - return -ENOSPC; - memmove(data, elem->data + 1, copied); + if (data) { + if (copied > data_len) + return -ENOSPC; + + memmove(data, elem->data + 1, copied); + } } else { copied = elem->datalen; - if (copied > data_len) - return -ENOSPC; - memmove(data, elem->data, copied); + if (data) { + if (copied > data_len) + return -ENOSPC; + + memmove(data, elem->data, copied); + } } /* Fragmented elements must have 255 bytes */ @@ -2532,10 +2538,13 @@ ssize_t cfg80211_defragment_element(const struct element *elem, const u8 *ies, elem_datalen = elem->datalen; - if (copied + elem_datalen > data_len) - return -ENOSPC; + if (data) { + if (copied + elem_datalen > data_len) + return -ENOSPC; + + memmove(data + copied, elem->data, elem_datalen); + } - memmove(data + copied, elem->data, elem_datalen); copied += elem_datalen; /* Only the last fragment may be short */ |