oss-fuzz: AddressSanitizer: stack-buffer-overflow in padding() src/looprestoration.c
reproduce with ./tests/dav1d_fuzzer clusterfuzz-testcase-minimized-dav1d_fuzzer-5731418676658176
clusterfuzz-testcase-minimized-dav1d_fuzzer-5731418676658176
==1==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7f0380841052 at pc 0x0000004ea31d bp 0x7ffd258d8290 sp 0x7ffd258d7a40
READ of size 6 at 0x7f0380841052 thread T0
SCARINESS: 45 (6-byte-read-stack-buffer-overflow-far-from-bounds)
#0 0x4ea31c in __asan_memcpy _asan_rtl_
#1 0x5d9e81 in padding /src/dav1d/src/looprestoration.c:90:13
#2 0x5d8c58 in wiener_c /src/dav1d/src/looprestoration.c:146:5
#3 0x5ff042 in lr_stripe /src/dav1d/src/lr_apply.c:165:13
#4 0x5fe7f3 in lr_sbrow /src/dav1d/src/lr_apply.c:254:13
#5 0x5fdfea in dav1d_lr_sbrow_16bpc /src/dav1d/src/lr_apply.c:276:9
#6 0x5ed2a6 in dav1d_filter_sbrow_16bpc /src/dav1d/src/recon.c:1482:9
#7 0x54b68a in dav1d_decode_frame /src/dav1d/src/decode.c:2669:25
#8 0x55075e in dav1d_submit_frame /src/dav1d/src/decode.c:3036:20
#9 0x538450 in dav1d_parse_obus /src/dav1d/src/obu.c:1106:20
#10 0x5356a6 in dav1d_decode /src/dav1d/src/lib.c:201:20
#11 0x53209b in LLVMFuzzerTestOneInput /src/dav1d/tests/libfuzzer/dav1d_fuzzer.c:82:19
#12 0x53003e in ExecuteFilesOnyByOne(int, char**) /src/libfuzzer/afl/afl_driver.cpp:301:5
#13 0x5305ae in main /src/libfuzzer/afl/afl_driver.cpp:339:12
#14 0x7f037f79c82f in __libc_start_main /build/glibc-Cl5G7W/glibc-2.23/csu/libc-start.c:291
#15 0x41c9b8 in _start