On 13/11/2018 13:04, Arend van Spriel wrote: > Several functions in efivars api assume __efivars is set, ie. will be > accessed after efivars_register() has been called. However, following > NULL pointer access was reported upon calling efivar_entry_size(). > > [ 14.177769] Unable to handle kernel NULL pointer dereference at > virtual address 00000008 > [ 14.197303] pgd = 60bfa5f1 > [ 14.211842] [00000008] *pgd=00000000 > [ 14.227373] Internal error: Oops: 5 [#1] SMP ARM > [ 14.244244] Modules linked in: brcmfmac sha256_generic sha256_arm snd cfg80211 brcmutil soundcore snd_soc_tegra30_ahub tegra_wdt > [ 14.269109] CPU: 1 PID: 114 Comm: kworker/1:2 Not tainted 4.20.0-rc1-next-20181107-gd881de3 #1 > [ 14.269114] Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) > [ 14.269154] Workqueue: events request_firmware_work_func > [ 14.269177] PC is at efivar_entry_size+0x28/0x90 > [ 14.269362] LR is at brcmf_fw_complete_request+0x3f8/0x8d4 [brcmfmac] > [ 14.269369] pc : [<c0c40718>] lr : [<bf2a3ef4>] psr: a00d0113 > [ 14.269374] sp : ede7fe28 ip : ee983410 fp : c1787f30 > [ 14.269378] r10: 00000000 r9 : 00000000 r8 : bf2b2258 > [ 14.269384] r7 : ee983000 r6 : c1604c48 r5 : ede7fe88 r4 : edf337c0 > [ 14.269389] r3 : 00000000 r2 : 00000000 r1 : ede7fe88 r0 : c17712c8 > [ 14.269398] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > [ 14.269404] Control: 10c5387d Table: ad16804a DAC: 00000051 > > Disassembly showed that the local static variable __efivars is NULL. Likely > because efivars_register() is not called on the Tegra platform. So adding > a NULL pointer check in efivar_entry_size() and similar functions while at > it. In efivars_register() a couple of sanity checks have been added. > > Cc: Hans de Goede <hdegoede@xxxxxxxxxx> > Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx> > Signed-off-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx> Thanks. This fixes the problem for me ... Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx> Cheers! Jon -- nvpublic
