On 05/20/20 at 02:22pm, Allan McRae wrote:

Given RFC 4880 provides the code to do this calculation, I am not sure how I managed to stuff that up! This bug was only exposed when a signature made with "include-key-block" was added to the Arch repos, which provided a subpacket with the required size to hit this issue.

LGTM. Though, it might be worth it to use + instead of | just so we match 4880 and extract_keyid exactly.

Signed-off-by: Allan McRae <allan@archlinux.org> ---

Also appropriate for 5.2.2

lib/libalpm/signing.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/libalpm/signing.c b/lib/libalpm/signing.c index c8eaaca2..422523b6 100644 --- a/lib/libalpm/signing.c +++ b/lib/libalpm/signing.c @@ -1058,7 +1058,7 @@ static int parse_subpacket(alpm_handle_t *handle, const char *identifier, if(length_check(len, spos, 2, handle, identifier) != 0){ return -1; } - slen = (sig[spos] << 8) | sig[spos + 1]; + slen = (((sig[spos] - 192) << 8) | sig[spos + 1]) + 192; spos = spos + 2; } else { if(length_check(len, spos, 5, handle, identifier) != 0) { -- 2.26.2