revert fix(kernel): array-index-out-of-bounds error on bpf

[nberlee]

7f9c802 can be reverted as the patch is included in 6.6.47

In Kernel 6.6.47 changelog:

commit ef33f0296893356314a5c79e787bca977bb3c9ec
Author: Kees Cook <kees@kernel.org>
Date:   Thu Feb 22 07:56:15 2024 -0800

    bpf: Replace bpf_lpm_trie_key 0-length array with flexible array
    
[..]

PS: the 6.6.49 kernel build should have failed, as it does on my build, I do not understand the patch was successful.

1.683 patching file Documentation/bpf/map_lpm_trie.rst
1.684 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.685 Apply anyway? [n]
1.685 Skipping patch.
1.686 1 out of 1 hunk ignored -- saving rejects to file Documentation/bpf/map_lpm_trie.rst.rej
1.689 patching file include/uapi/linux/bpf.h
1.689 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.689 Apply anyway? [n]
1.689 Skipping patch.
1.689 1 out of 1 hunk ignored -- saving rejects to file include/uapi/linux/bpf.h.rej
1.690 patching file kernel/bpf/lpm_trie.c
1.690 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.690 Apply anyway? [n]
1.690 Skipping patch.
1.691 9 out of 9 hunks ignored -- saving rejects to file kernel/bpf/lpm_trie.c.rej
1.692 patching file samples/bpf/map_perf_test_user.c
1.692 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.692 Apply anyway? [n]
1.692 Skipping patch.
1.692 1 out of 1 hunk ignored -- saving rejects to file samples/bpf/map_perf_test_user.c.rej
1.693 patching file samples/bpf/xdp_router_ipv4_user.c
1.693 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.693 Apply anyway? [n]
1.693 Skipping patch.
1.693 1 out of 1 hunk ignored -- saving rejects to file samples/bpf/xdp_router_ipv4_user.c.rej
1.695 patching file tools/include/uapi/linux/bpf.h
1.696 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.696 Apply anyway? [n]
1.696 Skipping patch.
1.696 1 out of 1 hunk ignored -- saving rejects to file tools/include/uapi/linux/bpf.h.rej
1.697 patching file tools/testing/selftests/bpf/progs/map_ptr_kern.c
1.697 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.697 Apply anyway? [n]
1.697 Skipping patch.
1.697 1 out of 1 hunk ignored -- saving rejects to file tools/testing/selftests/bpf/progs/map_ptr_kern.c.rej
1.698 patching file tools/testing/selftests/bpf/test_lpm_map.c
1.698 Reversed (or previously applied) patch detected!  Assume -R? [n]
1.698 Apply anyway? [n]
1.698 Skipping patch.
1.698 7 out of 7 hunks ignored -- saving rejects to file tools/testing/selftests/bpf/test_lpm_map.c.rej
1.712 Failed to apply patch /pkg/patches/0090-bpf-Replace-bpf_lpm_trie_key-0-length-array-with-flexible-array.patch
------
ERROR: failed to solve: process "/dev/.buildkit_qemu_emulator /toolchain/bin/bash -c set -eou pipefail\ncd /src\nfor patch in $(find /pkg/patches -type f -name \"*.patch\" | sort); do\n  patch -p1 < $patch || (echo \"Failed to apply patch $patch\" && exit 1)\ndone\n" did not complete successfully: exit code: 1
make[2]: *** [Makefile:116: target-kernel-build] Error 1
make[2]: Leaving directory '/home/nicob/repository/kernel'
make[1]: *** [Makefile:119: local-kernel-build] Error 2
make[1]: Leaving directory '/home/nicob/repository/kernel'
make: *** [Makefile:161: kernel-olddefconfig] Error 2

[smira]

Thank you, we'll drop the patch

[frezbo]

hmm i wonder why the patch failed to apply if it's already there 🤔

[smira]

Ok, I don't know how exactly that happened, but the patch filename contained 0x20 (space) at the end, so it never matched find -name *.patch, and never got applied.

ls -l kernel/build/patches/ | hexdump -C  
00000000  74 6f 74 61 6c 20 32 38  0a 2d 72 77 2d 72 77 2d  |total 28.-rw-rw-|
00000010  72 2d 2d 20 31 20 73 6d  69 72 61 20 73 6d 69 72  |r-- 1 smira smir|
00000020  61 20 32 32 36 37 39 20  53 65 70 20 31 30 20 31  |a 22679 Sep 10 1|
00000030  34 3a 32 33 20 30 30 30  31 2d 62 70 66 2d 52 65  |4:23 0001-bpf-Re|
00000040  70 6c 61 63 65 2d 62 70  66 5f 6c 70 6d 5f 74 72  |place-bpf_lpm_tr|
00000050  69 65 5f 6b 65 79 2d 30  2d 6c 65 6e 67 74 68 2d  |ie_key-0-length-|
00000060  61 72 72 61 79 2d 77 69  74 68 2d 66 6c 65 78 69  |array-with-flexi|
00000070  62 6c 65 2d 61 72 72 61  79 2e 70 61 74 63 68 20  |ble-array.patch |
00000080  0a 2d 72 77 2d 72 77 2d  72 2d 2d 20 31 20 73 6d  |.-rw-rw-r-- 1 sm|
00000090  69 72 61 20 73 6d 69 72  61 20 20 31 30 36 33 20  |ira smira  1063 |
000000a0  53 65 70 20 20 34 20 31  34 3a 32 31 20 52 45 41  |Sep  4 14:21 REA|
000000b0  44 4d 45 2e 6d 64 0a                              |DME.md.|