Affected: Linux

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

Add exception protection processing for vd in axi_chan_handle_err function

Since there is no protection for vd, a kernel panic will be triggered here in exceptional cases.

You can refer to the processing of axi_chan_block_xfer_complete function

The triggered kernel panic is as follows:

[ 67.848444] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 [ 67.848447] Mem abort info: [ 67.848449] ESR = 0x96000004 [ 67.848451] EC = 0x25: DABT (current EL), IL = 32 bits [ 67.848454] SET = 0, FnV = 0 [ 67.848456] EA = 0, S1PTW = 0 [ 67.848458] Data abort info: [ 67.848460] ISV = 0, ISS = 0x00000004 [ 67.848462] CM = 0, WnR = 0 [ 67.848465] user pgtable: 4k pages, 48-bit VAs, pgdp=00000800c4c0b000 [ 67.848468] [0000000000000060] pgd=0000000000000000, p4d=0000000000000000 [ 67.848472] Internal error: Oops: 96000004 [#1] SMP [ 67.848475] Modules linked in: dmatest [ 67.848479] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.100-emu_x2rc+ #11 [ 67.848483] pstate: 62000085 (nZCv daIf -PAN -UAO +TCO BTYPE=--) [ 67.848487] pc : axi_chan_handle_err+0xc4/0x230 [ 67.848491] lr : axi_chan_handle_err+0x30/0x230 [ 67.848493] sp : ffff0803fe55ae50 [ 67.848495] x29: ffff0803fe55ae50 x28: ffff800011212200 [ 67.848500] x27: ffff0800c42c0080 x26: ffff0800c097c080 [ 67.848504] x25: ffff800010d33880 x24: ffff80001139d850 [ 67.848508] x23: ffff08…