Steps to reproduce:

1) Download attached project 'WebCamTextureCrashReproProject.zip' and open in Unity
2) Build and run 'main' scene on a device
3) Keep pressing 'Start' button in ~ 2s interval
Note: After 3rd-20th time of pressing this button application should crash:
Fatal signal 11 (SIGSEGV), code 1, fault addr 0x9b1c3431 in tid 29290 (UnityHardwareCa)

Regression from: 5.5.2p1

Reproduced with:
5.5.2p1, 5.6.0b10

Not reproduced with:
5.3.7p4, 5.4.4p4, 5.5.2f1

DUT:

Motorola XT1032, OS:5.1, CPU:armeabi-v7a, GPU:Adreno (TM) 305, Build:motorola/falcon_retuglb/falcon_umts:5.1/LPBS23.13-58-2/2:user/release-keys
Lge LG D855 (G3), OS:5.0, CPU:armeabi-v7a, GPU:Adreno (TM) 330, Build:lge/g3_global_com/g3:5.0/LRX21R.A1445306351/1445306351:user/release-keys
Htc HTC 10, OS:6.0.1, CPU:arm64-v8a, GPU:Adreno (TM) 530, Build:htc/pmeuhl_00401/htc_pmeuhl:6.0.1/MMB29M/761759.1:user/release-keys
Samsung SM G930F (Galaxy S7), OS:7.0, CPU:arm64-v8a, GPU:Mali-T880, Build:samsung/heroltexx/herolte:7.0/NRD90M/G930FXXU1ZPK3:user/release-keys

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Fixed in: 5.5.4p2, 5.6.2p4