## Summary [Dissector bug, protocol BT ATT: C:\gitlab-builds\builds\-fyeYoMP\1\wireshark\wireshark\epan\proto.c:11710: failed assertion "hf->bitmask != 0" (btatt.battery_power_state.present)] The mask used for all the btatt.battery_power_state.* values is set to 0x0, but each value is 2 bits in size. See here: https://gitlab.com/wireshark/wireshark/-/blob/master/epan/dissectors/packet-btatt.c#L12827 ``` {&hf_btatt_battery_power_state_level, {"Level", "btatt.battery_power_state.level", FT_UINT8, BASE_HEX, VALS(battery_power_state_level_vals), 0x0, NULL, HFILL} }, {&hf_btatt_battery_power_state_charging, {"Charging", "btatt.battery_power_state.charging", FT_UINT8, BASE_HEX, VALS(battery_power_state_charging_vals), 0x0, NULL, HFILL} }, {&hf_btatt_battery_power_state_discharging, {"Discharging", "btatt.battery_power_state.discharging", FT_UINT8, BASE_HEX, VALS(battery_power_state_discharging_vals), 0x0, NULL, HFILL} }, {&hf_btatt_battery_power_state_present, {"Present", "btatt.battery_power_state.present", FT_UINT8, BASE_HEX, VALS(battery_power_state_present_vals), 0x0, NULL, HFILL} }, ``` The format of the battery_power_state byte is: ``` (2b level)(2b charging)(2b discharging)(2b present) ``` or put another way: ``` present << 0 discharging << 2 charging << 4 level << 6 ``` The `0xAB` (`0b10101011`) value in the example capture would thus decode to: ``` present: 0b11 discharging: 0b10 charging: 0b10 level: 0b10 ``` ## Steps to reproduce Sniff the packets of a Bluetooth LE device that has a complete btatt.battery_power_state characteristic, as it is read. I used nRF Sniffer with a nRF52840-Dongle adapter. ## What is the current bug behavior? Error/assertion is displayed and battery_power_state information is not decoded. ## What is the expected correct behavior? The battery_power_state attribute should be decoded/displayed correctly. ## Sample capture file [data-sync.pcapng](/uploads/b2c19e5e09e92667326746fcd1b6caf8/data-sync.pcapng) ## Relevant logs and/or screenshots ``` Frame 4665: 32 bytes on wire (256 bits), 32 bytes captured (256 bits) on interface COM12-3.6, id 0 nRF Sniffer for Bluetooth LE Bluetooth Low Energy Link Layer Access Address: 0x50654aa5 [Master Address: 79:bf:22:1f:38:d9 (79:bf:22:1f:38:d9)] [Slave Address: f9:70:ed:2f:e5:56 (f9:70:ed:2f:e5:56)] Data Header Bluetooth L2CAP Protocol Length: 2 CID: Attribute Protocol (0x0004) Bluetooth Attribute Protocol Opcode: Read Response (0x0b) [Handle: 0x0023 (Battery Service: Battery Power State)] [Service UUID: Battery Service (0x180f)] [UUID: Battery Power State (0x2a1a)] Battery Power State: 0xab [Dissector bug, protocol BT ATT: C:\gitlab-builds\builds\-fyeYoMP\1\wireshark\wireshark\epan\proto.c:11710: failed assertion "hf->bitmask != 0" (btatt.battery_power_state.present)] [Expert Info (Error/Malformed): C:\gitlab-builds\builds\-fyeYoMP\1\wireshark\wireshark\epan\proto.c:11710: failed assertion "hf->bitmask != 0" (btatt.battery_power_state.present)] [C:\gitlab-builds\builds\-fyeYoMP\1\wireshark\wireshark\epan\proto.c:11710: failed assertion "hf->bitmask != 0" (btatt.battery_power_state.present)] [Severity level: Error] [Group: Malformed] ``` ## Build information ``` 3.6.7 (v3.6.7-0-g4a304d7ec222) Compiled (64-bit) using Microsoft Visual Studio 2019 (VC++ 14.31, build 31107), with Qt 5.15.2, with libpcap, with GLib 2.66.4, with zlib 1.2.11, with Lua 5.2.4, with GnuTLS 3.6.3 and PKCS #11 support, with Gcrypt 1.8.3, with MIT Kerberos, with MaxMind DB resolver, with nghttp2 1.44.0, with brotli, with LZ4, with Zstandard, with Snappy, with libxml2 2.9.10, with libsmi 0.4.8, with QtMultimedia, with automatic updates using WinSparkle 0.5.7, with AirPcap, with SpeexDSP (using bundled resampler), with Minizip. Running on 64-bit Windows 10 (21H2), build 19044, with Intel(R) Core(TM) i7-8850H CPU @ 2.60GHz (with SSE4.2), with 32272 MB of physical memory, with GLib 2.66.4, with Qt 5.15.2, with Npcap version 1.60, based on libpcap version 1.10.2-PRE-GIT, with c-ares 1.17.0, with GnuTLS 3.6.3, with Gcrypt 1.8.3, with nghttp2 1.44.0, with brotli 1.0.9, with LZ4 1.9.3, with Zstandard 1.4.0, without AirPcap, with light display mode, with HiDPI, with LC_TYPE=English_Australia.utf8, binary plugins supported (21 loaded). ```