Crash in `std.crypto.tls.Client.readvAdvanced`.

[tomasz-lisowski]

Zig Version

0.11.0-dev.3105+e46d7a369

Steps to Reproduce and Observed Behavior

This is the example copied from: zig/test/standalone/http.zig with the offending URL pasted in, instead of the local target. I don't see an easy way to record and include the exact behavior of the server for perfect repeatability. Best I can do is to archive the page although I doubt that helps much.

pub fn main() !void {
    var alloc_gp = std.heap.GeneralPurposeAllocator(.{}){};
    var alloc = alloc_gp.allocator();
    defer _ = alloc_gp.deinit();

    var client = std.http.Client{ .allocator = alloc };
    defer client.deinit();

    var h = std.http.Headers{ .allocator = alloc };
    defer h.deinit();

    const location = try std.fmt.allocPrint(alloc, "https://apps.apple.com/us/app/google-chrome/id535886823", .{});
    defer alloc.free(location);
    const uri = try std.Uri.parse(location);

    std.log.info("{s}", .{location});
    var req = try client.request(.GET, uri, h, .{});
    defer req.deinit();

    try req.start();
    try req.wait();

    const body = try req.reader().readAllAlloc(alloc, 16_777_216);
    defer alloc.free(body);

    std.log.info("Body: {s}.", .{body});
}

This causes:

thread 1234567 panic: @memcpy arguments have non-equal lengths
/zig/std/crypto/tls/Client.zig:1062:25: 0x392ebb in readvAdvanced__anon_9848
            @memcpy(frag[0..in], first);

When replacing in with first.len causes:

thread 1234567 panic: @memcpy arguments alias
/zig/std/crypto/tls/Client.zig:1062:25: 0x392f17 in readvAdvanced__anon_9848
            @memcpy(frag[0..first.len], first);

Replacing the @memcpy with std.mem.copyForwards gives:

thread 1234567 panic: index out of bounds: index 16384, len 14332
/zig/std/crypto/tls/Client.zig:1180:45: 0x396fc4 in readvAdvanced__anon_9848
                                @memcpy(dest[0..msg.len], msg);

Expected Behavior

The body of the web page inside body.

[Vexu]

Duplicate of #15590