Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: btnxpuart: Fix Null pointer dereference in btnxpuart_flush()

This adds a check before freeing the rx->skb in flush and close functions to handle the kernel crash seen while removing driver after FW download fails or before FW download completes.

dmesg log: [ 54.634586] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000080 [ 54.643398] Mem abort info: [ 54.646204] ESR = 0x0000000096000004 [ 54.649964] EC = 0x25: DABT (current EL), IL = 32 bits [ 54.655286] SET = 0, FnV = 0 [ 54.658348] EA = 0, S1PTW = 0 [ 54.661498] FSC = 0x04: level 0 translation fault [ 54.666391] Data abort info: [ 54.669273] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 54.674768] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 54.674771] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 54.674775] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000048860000 [ 54.674780] [0000000000000080] pgd=0000000000000000, p4d=0000000000000000 [ 54.703880] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 54.710152] Modules linked in: btnxpuart(-) overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce polyval_generic snd_soc_imx_spdif snd_soc_imx_card snd_soc_ak5558 snd_soc_ak4458 caam secvio error snd_soc_fsl_micfil snd_soc_fsl_spdif snd_soc_fsl_sai snd_soc_fsl_utils imx_pcm_dma gpio_ir_recv rc_co…