DCL via memory in dart investigation and questions

Ttremble1256 · 23 Feb

I noticed that a lot of the apps I am trying to use on GrapheneOS require DCL via memory so I decided to investigate if there was any common thread among them. The two open source apps I looked at were Flexify and BlueBubbles.

https://github.com/brandonp2412/Flexify/tree/main
https://github.com/BlueBubblesApp/bluebubbles-app/tree/master

Looking at the crash logs for these apps with DCL via memory disabled, I found that a common thread was their use of the Dart VM in flutter.

FLEXIFY:

-- switch to crash
02-22 20:17:24.380 11489 11489 F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
02-22 20:17:24.380 11489 11489 F DEBUG   : Build fingerprint: 'google/shiba/shiba:15/AP4A.250205.002/2025021100:user/release-keys'
02-22 20:17:24.380 11489 11489 F DEBUG   : Revision: 'MP1.0'
02-22 20:17:24.380 11489 11489 F DEBUG   : ABI: 'arm64'
02-22 20:17:24.380 11489 11489 F DEBUG   : Timestamp: 2025-02-22 15:17:24.243156902-0500
02-22 20:17:24.380 11489 11489 F DEBUG   : Process uptime: 1s
02-22 20:17:24.380 11489 11489 F DEBUG   : Cmdline: com.presley.flexify
02-22 20:17:24.380 11489 11489 F DEBUG   : pid: 11426, tid: 11484, name: DartWorker  >>> com.presley.flexify <<<
02-22 20:17:24.380 11489 11489 F DEBUG   : uid: 10158
02-22 20:17:24.380 11489 11489 F DEBUG   : tagged_addr_ctrl: 000000000007fff7 (PR_TAGGED_ADDR_ENABLE, PR_MTE_TCF_SYNC, PR_MTE_TCF_ASYNC, mask 0xfffe)
02-22 20:17:24.380 11489 11489 F DEBUG   : pac_enabled_keys: 000000000000000f (PR_PAC_APIAKEY, PR_PAC_APIBKEY, PR_PAC_APDAKEY, PR_PAC_APDBKEY)
02-22 20:17:24.380 11489 11489 F DEBUG   : signal 6 (SIGABRT), code -1 (SI_QUEUE), fault addr --------
02-22 20:17:24.380 11489 11489 F DEBUG   : Abort message: '../../../flutter/third_party/dart/runtime/vm/virtual_memory_posix.cc: 428: error: mprotect failed: 13 (Permission denied)'
02-22 20:17:24.380 11489 11489 F DEBUG   :     x0  0000000000000000  x1  0000000000002cdc  x2  0000000000000006  x3  0000dba7c9f0ff70
02-22 20:17:24.380 11489 11489 F DEBUG   :     x4  000000000000000a  x5  000000000000000a  x6  000000000000000a  x7  0320303780808080
02-22 20:17:24.380 11489 11489 F DEBUG   :     x8  00000000000000f0  x9  8367a3947614f100  x10 0000000000000001  x11 0000dede902e7250
02-22 20:17:24.380 11489 11489 F DEBUG   :     x12 0000dba7c9f0d740  x13 000000000000007b  x14 0000dba7c9f0d7f0  x15 000005e23bccd8c6
02-22 20:17:24.380 11489 11489 F DEBUG   :     x16 0000dede90351290  x17 0000dede9033ca00  x18 0000dba737de0000  x19 0000000000002ca2
02-22 20:17:24.380 11489 11489 F DEBUG   :     x20 0000000000002cdc  x21 00000000ffffffff  x22 0000dba7c9f3e040  x23 0b00dc283e7a4c60
02-22 20:17:24.380 11489 11489 F DEBUG   :     x24 fffffffffffff000  x25 0000000000011000  x26 0000dba7d83a8000  x27 0100dd5dddfebc00
02-22 20:17:24.380 11489 11489 F DEBUG   :     x28 0000000000000005  x29 0000dba7c9f0fff0
02-22 20:17:24.380 11489 11489 F DEBUG   :     lr  0000dede902cdc4c  sp  0000dba7c9f0ff70  pc  0000dede902cdc70  pst 0000000000001000
02-22 20:17:24.380 11489 11489 F DEBUG   : 36 total frames
02-22 20:17:24.380 11489 11489 F DEBUG   : backtrace:
02-22 20:17:24.380 11489 11489 F DEBUG   :       #00 pc 0000000000067c70  /apex/com.android.runtime/lib64/bionic/libc.so (abort+160) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #01 pc 0000000000837c1c  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #02 pc 000000000087116c  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #03 pc 0000000000871204  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #04 pc 000000000084a8f4  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #05 pc 0000000000889050  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #06 pc 0000000000889780  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #07 pc 00000000002c4048  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #08 pc 00000000003986b0  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #09 pc 0000000000398d14  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #10 pc 0000000000397d34  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #11 pc 0000000000397284  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #12 pc 0000000000396e50  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #13 pc 0000000000706b24  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #14 pc 00000000007069fc  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #15 pc 0000000000706464  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #16 pc 0000000000756594  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #17 pc 00000000002ce73c  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #18 pc 00000000002ce5c8  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #19 pc 00000000002cb840  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #20 pc 00000000002cb4a4  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #21 pc 00000000002cb410  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #22 pc 00000000002cb260  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #23 pc 00000000002cb158  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #24 pc 00000000002cb11c  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #25 pc 00000000002e46d0  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #26 pc 00000000002e4674  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #27 pc 00000000002c3d3c  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libapp.so (BuildId: 369f5a6fdf31e2684822a5e2e2302103)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #28 pc 000000000086b500  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #29 pc 0000000000876fb8  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #30 pc 000000000087be28  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #31 pc 000000000087bc78  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #32 pc 00000000009122c0  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #33 pc 00000000008d5f34  /data/app/~~T1KvpNJkI7UN0tUppTMS-g==/com.presley.flexify-Uviykr5YNBBAjNeUJEVwWA==/lib/arm64/libflutter.so (BuildId: fa30a3aeecc8debd0d43411c85ed486060157f89)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #34 pc 000000000007ba94  /apex/com.android.runtime/lib64/bionic/libc.so (__pthread_start(void*)+132) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)
02-22 20:17:24.380 11489 11489 F DEBUG   :       #35 pc 000000000006b474  /apex/com.android.runtime/lib64/bionic/libc.so (__start_thread+68) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)

BlueBubbles:

-- switch to crash
02-22 20:38:59.956 13538 13538 F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
02-22 20:38:59.956 13538 13538 F DEBUG   : Build fingerprint: 'google/shiba/shiba:15/AP4A.250205.002/2025021100:user/release-keys'
02-22 20:38:59.956 13538 13538 F DEBUG   : Revision: 'MP1.0'
02-22 20:38:59.956 13538 13538 F DEBUG   : ABI: 'arm64'
02-22 20:38:59.956 13538 13538 F DEBUG   : Timestamp: 2025-02-22 15:38:59.803401202-0500
02-22 20:38:59.956 13538 13538 F DEBUG   : Process uptime: 2s
02-22 20:38:59.956 13538 13538 F DEBUG   : Cmdline: com.bluebubbles.messaging
02-22 20:38:59.956 13538 13538 F DEBUG   : pid: 13461, tid: 13519, name: 1.ui  >>> com.bluebubbles.messaging <<<
02-22 20:38:59.956 13538 13538 F DEBUG   : uid: 10203
02-22 20:38:59.956 13538 13538 F DEBUG   : tagged_addr_ctrl: 000000000007fff7 (PR_TAGGED_ADDR_ENABLE, PR_MTE_TCF_SYNC, PR_MTE_TCF_ASYNC, mask 0xfffe)
02-22 20:38:59.956 13538 13538 F DEBUG   : pac_enabled_keys: 000000000000000f (PR_PAC_APIAKEY, PR_PAC_APIBKEY, PR_PAC_APDAKEY, PR_PAC_APDBKEY)
02-22 20:38:59.956 13538 13538 F DEBUG   : signal 6 (SIGABRT), code -1 (SI_QUEUE), fault addr --------
02-22 20:38:59.956 13538 13538 F DEBUG   : Abort message: '../../../flutter/third_party/dart/runtime/vm/virtual_memory_posix.cc: 428: error: mprotect failed: 13 (Permission denied)'
02-22 20:38:59.956 13538 13538 F DEBUG   :     x0  0000000000000000  x1  00000000000034cf  x2  0000000000000006  x3  0000d6c4c0d52e10
02-22 20:38:59.956 13538 13538 F DEBUG   :     x4  000000000000000a  x5  000000000000000a  x6  000000000000000a  x7  0320303780808080
02-22 20:38:59.956 13538 13538 F DEBUG   :     x8  00000000000000f0  x9  7a8463b05dcb7f00  x10 0000000000000001  x11 0000da03d90d3250
02-22 20:38:59.956 13538 13538 F DEBUG   :     x12 0000d6c4c0d505e0  x13 000000000000007b  x14 0000d6c4c0d50690  x15 000005e9a5993133
02-22 20:38:59.956 13538 13538 F DEBUG   :     x16 0000da03d913d290  x17 0000da03d9128a00  x18 0000d6c43a920000  x19 0000000000003495
02-22 20:38:59.956 13538 13538 F DEBUG   :     x20 00000000000034cf  x21 00000000ffffffff  x22 0000d6c4c0d92040  x23 0600d7367a122528
02-22 20:38:59.956 13538 13538 F DEBUG   :     x24 fffffffffffff000  x25 0000000000011000  x26 0000d6c43d091000  x27 0000d6c43ce8103c
02-22 20:38:59.956 13538 13538 F DEBUG   :     x28 0000000000000005  x29 0000d6c4c0d52e90
02-22 20:38:59.956 13538 13538 F DEBUG   :     lr  0000da03d90b9c4c  sp  0000d6c4c0d52e10  pc  0000da03d90b9c70  pst 0000000000001000
02-22 20:38:59.956 13538 13538 F DEBUG   : 49 total frames
02-22 20:38:59.956 13538 13538 F DEBUG   : backtrace:
02-22 20:38:59.956 13538 13538 F DEBUG   :       #00 pc 0000000000067c70  /apex/com.android.runtime/lib64/bionic/libc.so (abort+160) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #01 pc 0000000000829918  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #02 pc 0000000000860a6c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #03 pc 0000000000860b04  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #04 pc 0000000000846838  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #05 pc 00000000008792ec  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #06 pc 00000000008799a4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #07 pc 0000000000894068  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #08 pc 0000000000fbffc4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #09 pc 0000000000fbff3c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #10 pc 0000000001ad0c68  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #11 pc 0000000000fbfeec  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #12 pc 0000000001ad0c68  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #13 pc 0000000001071aec  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #14 pc 00000000014225a0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #15 pc 00000000008a22f0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #16 pc 00000000008a23e0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #17 pc 0000000001a06a98  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #18 pc 0000000001a0670c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #19 pc 00000000019a1b64  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #20 pc 00000000019b7518  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #21 pc 0000000000920ea0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #22 pc 0000000000920dc4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #23 pc 00000000008a2e0c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #24 pc 00000000008a2ef4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #25 pc 0000000001a05110  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #26 pc 00000000019eb51c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #27 pc 00000000019ea5c0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #28 pc 00000000008a2e38  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #29 pc 00000000008a2ef4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #30 pc 0000000001a05110  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #31 pc 00000000019eb51c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #32 pc 00000000019ea5c0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #33 pc 000000000089f5a4  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #34 pc 000000000089f49c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #35 pc 000000000089f460  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #36 pc 0000000000893d5c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libapp.so (BuildId: 63956a450c250c2f1f6330ba9ebebcb4)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #37 pc 000000000085afe0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #38 pc 000000000099ade8  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #39 pc 00000000007c3d4c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #40 pc 0000000000475bec  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #41 pc 00000000004797d0  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #42 pc 0000000000010644  /system/lib64/libutils.so (android::Looper::pollOnce(int, int*, int*, void**)+948) (BuildId: 6e1cde1bbedf9fc6069a4b2d923f6ecb)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #43 pc 000000000001f378  /system/lib64/libandroid.so (ALooper_pollOnce+104) (BuildId: 854880759ababf7807f402e036f9486c)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #44 pc 00000000004798dc  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #45 pc 0000000000477938  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #46 pc 000000000047772c  /data/app/~~szGSq7DESezM2Axnjh1xzQ==/com.bluebubbles.messaging-ciwNDZIdAoiGVaO-bOXmcA==/lib/arm64/libflutter.so (BuildId: 0bb05f781d5387e7180505dd31219075e4e0edc9)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #47 pc 000000000007ba94  /apex/com.android.runtime/lib64/bionic/libc.so (__pthread_start(void*)+132) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)
02-22 20:38:59.956 13538 13538 F DEBUG   :       #48 pc 000000000006b474  /apex/com.android.runtime/lib64/bionic/libc.so (__start_thread+68) (BuildId: fe8b97e9782214f6ebc2c8cb074c059d)
--------- switch to events
02-22 20:38:59.989 13461 13461 I wm_on_top_resumed_lost_called: [Token=98038052,Component Name=com.bluebubbles.messaging.MainActivity,Reason=topStateChangedWhenResumed]
02-22 20:38:59.994 13461 13461 I wm_on_paused_called: [Token=98038052,Component Name=com.bluebubbles.messaging.MainActivity,Reason=performPause,time=2ms]

After some digging into a past instance of media-kit crashing in Aves gallery, it seems that they found a workaround to the underlying Dart issue using an isolate event loop. This is because the issue was stemming from NativeCallables requiring DCL.

https://github.com/deckerst/aves/issues/1271
https://github.com/media-kit/media-kit/pull/1022
https://github.com/media-kit/media-kit/issues/1015

Based on what I could glean from other online sources, my understanding is that when a Dart app uses native plugins (which rely on dart:ffi to communicate with native code), it can trigger operations within the Dart VM that require DCL via memory. Those operations seem to be related to how the Dart VM manages memory and handles callbacks when interacting with native code via FFI.

Unfortunately my technical understanding of all these things is very limited, so I would appreciate the opinions of someone more knowledgeable.

Is this a flutter problem where certain plugins that rely on native code require DCL via memory?

And who can solve this problem? Is it on app developers to find plugins without that reliance? Is it on plugins like media-kit to find a work around using dart-based memory control functions? Or does the dart sdk need to be improved to account for this edge case?

Iignoramous · 23 Feb

(going by the links you've shared)

tremble1256 this a flutter problem where certain plugins that rely on native code require DCL via memory

For MediaKit, it is a Dart VM problem, which tries to do typical VM things (like allocate executable memory pages & mprotect) and gets rekt on iOS, Fuschia, and now on GrapheneOS. Unfortunately, Dart expects to get rekt on those other platforms but not on Android (GrapheneOS) and hence the crash.

who can solve that problem?

As the commit you've shared shows, MediaKit and other SDKs can workaround this with Dart VM's "Isolates".

As for Dart VM, it'd be better if it handled mprotect failures on Android like it handles on iOS and Fuschia?

As a user, use such apps selectively (for example, some large games seem to require DCL). Loading & executing code at runtime is a security issue.

See also this discussion on a similar (W ^ X) restriction: https://news.ycombinator.com/item?id=11789169

Iignoramous · 23 Feb

tremble1256 DCL via memory

This one and another question on "DCL" restrictions prompted me to go through DCL-related code and it seems like GrapheneOS does way more than prevent loading of in-memory or on-external-storage dexfiles.

Specifically, selinux policies (execmem/execmod) relating to "dynamic code loading" (DCL) are applied during app process bringup aka zygote specialization (some commits for reference: 1, 2, 3).

Given that, you have to think of GrapheneOS' DCL restrictions as running iOS in "lockdown mode". If you're paranoid that your device is comprised or you're being targeted by competent malicious actors, you must not allow any app to DCL via memory & storage (in addition to enabling MTE globally). Otherwise, I'd say, it is okay to enable memory and/or storage on a case-by-case basis (as there's legitimate usecase for both, otherwise).